U.S. patent application number 15/989572 was filed with the patent office on 2018-09-27 for thermoplastic compositions having low smoke, methods of their manufacture, and uses thereof.
The applicant listed for this patent is SABIC GLOBAL TECHNOLOGIES B.V.. Invention is credited to ROLAND SEBASTIAN ASSINK, PAUL DEAN SYBERT, ROBERT DIRK VAN DE GRAMPEL, MARK ADRIANUS JOHANNES VAN DER MEE.
Application Number | 20180273751 15/989572 |
Document ID | / |
Family ID | 47884567 |
Filed Date | 2018-09-27 |
United States Patent
Application |
20180273751 |
Kind Code |
A1 |
VAN DER MEE; MARK ADRIANUS JOHANNES
; et al. |
September 27, 2018 |
THERMOPLASTIC COMPOSITIONS HAVING LOW SMOKE, METHODS OF THEIR
MANUFACTURE, AND USES THEREOF
Abstract
A low smoke density thermoplastic composition comprising, based
on the total weight of the thermoplastic composition, 70 to 95 wt %
of a polycarbonate copolymer comprising first repeating units and
second repeating units, wherein the first repeating units are not
the same as the second repeating units, and wherein the first
repeating units are bisphenol carbonate units of the formula
##STR00001## wherein R.sup.a and R.sup.b are each independently
C.sub.1-12 alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or
C.sub.1-12 alkoxy, p and q are each independently 0 to 4, and
X.sup.a is a single bond, --O--, --S--, --S(O)--, --S(O).sub.2--,
--C(O)--, a C.sub.1-11 alkylidene of formula
--C(R.sup.c)(R.sup.d)-- wherein R.sup.c and R.sup.d are each
independently hydrogen or C.sub.1-10 alkyl, or a group of the
formula --C(.dbd.R.sup.e)-- wherein R.sup.e is a divalent
C.sub.1-10 hydrocarbon group; and the second repeating units
comprise bisphenol carbonate units that are not the same as the
first repeating bisphenol carbonate units, siloxane units, arylate
ester units, or a combination of arylate ester units and siloxane
units; and 5 to 30 wt % of a polyetherimide based on the weight of
the composition, wherein an article molded from the composition has
a smoke density (Ds-4) value of equal to or less than 300 as
measured by ISO 5659-2 on a 3 mm thick plaque.
Inventors: |
VAN DER MEE; MARK ADRIANUS
JOHANNES; (BREDA, NL) ; VAN DE GRAMPEL; ROBERT
DIRK; (THOLEN, NL) ; ASSINK; ROLAND SEBASTIAN;
(MIDDELBURG, NL) ; SYBERT; PAUL DEAN; (EVANSVILLE,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SABIC GLOBAL TECHNOLOGIES B.V. |
Bergen Op Zoom |
|
NL |
|
|
Family ID: |
47884567 |
Appl. No.: |
15/989572 |
Filed: |
May 25, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15061514 |
Mar 4, 2016 |
9994709 |
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15989572 |
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13780430 |
Feb 28, 2013 |
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15061514 |
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61604861 |
Feb 29, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 2201/02 20130101;
C08G 77/448 20130101; C08L 79/04 20130101; B32B 5/00 20130101; B32B
27/365 20130101; C08L 69/005 20130101; C08L 83/10 20130101; C08L
69/00 20130101; C08G 73/1046 20130101; C08K 5/49 20130101; C08L
79/08 20130101; C09K 21/14 20130101; C08L 83/10 20130101; C08L
79/08 20130101; C08L 69/00 20130101; C08K 5/49 20130101; C08L 79/08
20130101; C08L 69/005 20130101; C08K 5/49 20130101; C08L 79/08
20130101 |
International
Class: |
C08L 69/00 20060101
C08L069/00; C09K 21/14 20060101 C09K021/14; B32B 27/36 20060101
B32B027/36; C08K 5/49 20060101 C08K005/49; C08L 83/10 20060101
C08L083/10; C08L 79/08 20060101 C08L079/08; C08L 79/04 20060101
C08L079/04; B32B 5/00 20060101 B32B005/00 |
Claims
1.-7. (canceled)
8. comprising, based on the total weight of the thermoplastic
composition, 70 to 95 wt % of a polycarbonate copolymer comprising
first repeating units and second repeating units, wherein the first
repeating units are not the same as the second repeating units, and
wherein the first repeating units are bisphenol carbonate units of
the formula ##STR00043## wherein R.sup.a and R.sup.b are each
independently C.sub.1-12 alkyl, C.sub.1-12 alkenyl, C.sub.3-8
cycloalkyl, or C.sub.1-12 alkoxy, p and q are each independently 0
to 4, and X.sup.a is a single bond, --O--, --S--, --S(O)--,
--S(O).sub.2--, --C(O)--, a C.sub.1-11 alkylidene of formula
--C(R.sup.c)(R.sup.d)-- wherein R.sup.c and R.sup.d are each
independently hydrogen or C.sub.1-10 alkyl, or a group of the
formula --C(.dbd.R.sup.e)-- wherein R.sup.e is a divalent
C.sub.1-10 hydrocarbon group; and the second repeating units are
carbonate units of the formula ##STR00044## wherein R.sup.a and
R.sup.b are each independently a C.sub.1-3 alkyl group, p and q are
each independently integers of 0 to 4, R.sup.3 is each
independently a C.sub.1-6 alkyl group, j is 0 to 4, and R.sup.4 is
hydrogen, C.sub.1-6 alkyl, or phenyl optionally substituted with 1
to 5 C.sub.1-6 alkyl groups, and 5 to 30 wt % of a polyetherimide
based on the weight of the composition, wherein an article molded
from the composition has smoke density after 4 minutes (Ds-4) of
less than or equal to 300 as measured by ISO 5659-2 on a 3 mm thick
plaque.
9. The composition of claim 8, wherein the second repeating units
are carbonate units of the formula ##STR00045## wherein R.sup.5 is
hydrogen, C.sub.1-6 alkyl, or phenyl optionally substituted with 1
to 5 C.sub.1-6 alkyl groups.
10. The composition of claim 9, wherein R.sup.5 is phenyl.
11.-16. (canceled)
17. A thermoplastic composition comprising, based on the total
weight of the thermoplastic composition, 70 to 95 wt % of a
polycarbonate copolymer comprising first repeating units and second
repeating units, wherein the first repeating units are not the same
as the second repeating units, and wherein the first repeating
units are bisphenol carbonate units of the formula ##STR00046##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12
alkoxy, P and q are each independently 0 to 4, and X.sup.a is a
single bond, --O--, --S--, --S(O)--, --S(O).sub.2--, --C(O)--, a
C.sub.1-11 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen or C.sub.1-10
alkyl, or a group of the formula --C(.dbd.R.sup.e)-- wherein
R.sup.e is a divalent C.sub.1-10 hydrocarbon group; and the second
repeating units comprise arylate ester units of the formula
##STR00047## optionally, monoaryl carbonate units of the formula
##STR00048## and optionally, bisphenol ester units of the formula
##STR00049## wherein, in the foregoing formulas R.sup.h is each
independently a C.sub.1-10 hydrocarbon group, n is 0 to 4, R.sup.a
and R.sup.b are each independently a C.sub.1-12 alkyl, p and q are
each independently integers of 0 to 4, and X.sup.a is a single
bond, --O--, --S--, --S(O)--, --S(O).sub.2--, --C(O)--, or a
C.sub.1-13 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen or C.sub.1-12
alkyl, or a group of the formula --C(.dbd.R.sup.e)-- wherein
R.sup.e is a divalent C.sub.1-12 hydrocarbon group, 5 to 30 wt % of
a polyetherimide based on the weight of the composition, wherein
the composition further comprises an organophosphorus compound in
an amount effective to provide 0.1-1 wt % phosphorus, based on the
total weight of the composition, and wherein the aromatic
organophosphorus compound is of the formula ##STR00050## wherein
each of R.sup.16, R.sup.17, R.sup.18, and R.sup.19 is phenyl, X is
of the formula ##STR00051## each n is 1, and p is 1-5, wherein an
article molded from the composition has smoke density after 4
minutes (Ds-4) of less than or equal to 300 as measured by ISO
5659-2 on a 3 mm thick plaque.
18. The composition of claim 17, wherein the polycarbonate
copolymer comprises 2 to 20 mol % of bisphenol-A carbonate units,
60 to 98 mol % of isophthalic acid-terephthalic acid-resorcinol
ester units, and optionally, 1 to 20 mol % resorcinol carbonate
units, isophthalic acid-terephthalic acid-bisphenol-A ester units,
or a combination thereof.
19. The composition of claim 18, wherein an article molded from the
composition has a smoke density (Ds-4) value of equal to or less
than 150 as measured by ISO 5659-2 on a 3 mm thick plaque.
20.-30. (canceled)
31. The composition of claim 8, wherein the polyetherimide
comprises units of the formula ##STR00052## wherein R is a
C.sub.2-20 hydrocarbon group, and Z is an aromatic C.sub.6-24
monocyclic or polycyclic group optionally substituted with 1 to 6
C.sub.1-8 alkyl groups, 1 to 8 halogen atoms, or a combination
thereof, wherein the divalent bonds of the --O--Z--O-- group are in
the 3,3', 3,4', 4,3', or the 4,4' positions.
32. The composition of claim 31, wherein R is a divalent radical of
the formula ##STR00053## wherein Q is --O--, --S--, --C(O)--,
--SO.sub.2--, --SO--, or --C.sub.yH.sub.2y-- or a halogenated
derivative thereof. wherein y is an integer from 1 to 5, and Z is a
divalent group of the formula ##STR00054## wherein Q.sup.1 is
--O--, --S--, --C(O)--, --SO.sub.2--, --SO--, or
--C.sub.yH.sub.2y-- wherein y is an integer from 1 to 5.
33. The composition of claim 32, wherein R is m-phenylene and
Q.sup.1 is isopropylidene.
34. The composition of claim 8, further comprising an
organophosphorus compound in an amount effective to provide 0.1-1
wt % phosphorus, based on the total weight of the composition.
35. The composition claim 34, wherein the organophosphorus compound
is an aromatic organophosphorus compounds having at least one
organic aromatic group and at least one phosphorus-containing
group, or an organic compounds having at least one
phosphorus-nitrogen bond.
36. The composition of claim 35, wherein the aromatic
organophosphorus compound comprises a C.sub.3-30 aromatic group and
a phosphate group, phosphite group, phosphonate group, phosphinate
group, phosphine oxide group, phosphine group, phosphazene, or a
combination comprising at least one of the foregoing
phosphorus-containing groups.
37. The composition of claim 36, wherein the aromatic
organophosphorus compound is of the formula ##STR00055## wherein
R.sup.16, R.sup.17, R.sup.18 and R.sup.19 are each independently
C.sub.1-8 alkyl, C.sub.5-6 cycloalkyl, C.sub.6-20 aryl, or
C.sub.7-12 arylalkylene, each optionally substituted by C.sub.1-12
alkyl, and X is a mono- or poly-nuclear aromatic C.sub.6-30 moiety
or a linear or branched C.sub.2-30 aliphatic radical, which can be
OH-substituted and can contain up to 8 ether bonds, provided that
at least one of R.sup.16, R.sup.17, R.sup.18, R.sup.19, and X is
aromatic, n is each independently 0 or 1, and q is from 0.5 to
30.
38. The composition of claim 37, wherein each of R.sup.16,
R.sup.17, R.sup.18, and R.sup.19 is phenyl, X is of the formula
##STR00056## each n is 1, and p is 1-5.
39. The composition of claim 35, wherein the aromatic
organophosphorus compound is bisphenol-A bis(diphenyl phosphate),
triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl
phosphate, or a combination comprising at least one of the
foregoing.
40. The composition of claim 8, wherein no halogenated compounds
are present.
41. The composition of claim 8, wherein an increase in fractional
concentration of polyetherimide in the composition reduces the
smoke density (Ds-4) as measured in accordance with ISO 5659-2 on a
3 mm thick plaque in a non-linear manner, wherein an interaction
parameter `k` measured using the equation Ds Blend = w POL Ds POL
pure + kw PEI Ds PEI pure w POL + kw PEI ##EQU00003## where
Ds.sub.Blend is the smoke density of the composition; w.sub.POL is
the fractional wt % of the non-polyetherimide
polymer(s)/copolymer(s) or their blends based on the weight of the
composition; W.sub.PEI is the fractional wt % of the polyetherimide
based on the weight of the composition; Ds.sub.POL.sup.pure is the
smoke density of the composition with only the non-polyetherimide
polymer(s)/copolymer(s); Ds.sub.PEI.sup.pure is the smoke density
of the composition with only polyetherimide; and k is greater than
4.0.
42. An article selected from a molded article, a thermoformed
article, an extruded film, an extruded sheet, a foamed article, one
or more layers of a multi-layer article, a substrate for a coated
article, and a substrate for a metallized article comprising the
composition of claim 8.
43. The article of claim 42, having a thickness of 0.1 to 10
mm.
44. The article of claim 43, having a thickness of 0.5 to 5 mm.
45. The article of claim 42, wherein the article is a
transportation component.
46. The article of claim 45, selected from a train or aircraft
interior component, wherein the component is a partition, a room
divider, a seat back, a food tray, a trim panel, an interior
display panel, an interior wall, a side wall, an end wall, a
ceiling panel, a door lining, a flap, a box, a hood, a louver, an
insulation material, a handle, a body shell for a window, a window
frame, an enclosure for an electronic device, a door, a luggage
rack, a luggage container, an interior side of a gangway membrane,
an interior lining of a gangway, or a component of a luggage
compartment, a display unit, a television, a refrigerator door, a
tray table, a food cart, a magazine rack, an air flow regulator, a
door, a table, or a seat.
47. A method of manufacture of an article, comprising molding,
extruding, or casting the thermoplastic composition of claim 8 to
form the article.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Patent
Application No. 61/604,861, filed Feb. 29, 2012, which is
incorporated by reference in its entirety herein.
BACKGROUND
[0002] This disclosure is directed to flame retardant thermoplastic
compositions having unexpectedly low smoke density, their methods
of manufacture, and methods of use thereof. The compositions are
especially useful in the manufacture of components for mass
transportation applications, such as rail.
[0003] Polycarbonates are useful in a wide variety of applications
at least in part because of their good balance of properties, such
as moldability, heat resistance and impact properties among others.
However, standards for flame retardancy properties such as flame
spread, heat release, and smoke generation upon burning have become
increasingly stringent, particularly in applications used in mass
transportation (aircraft, trains, and ships), as well as building
and construction. For example, the European Union has approved the
introduction of a new harmonized fire standard for rail
applications, namely EN-45545, to replace all currently active
different standards in each member state. This norm will impose
stringent requirements on smoke density and heat release properties
allowed for materials used in these applications. Smoke density
(Ds-4) in EN-45545 is the smoke density after 4 minutes determined
in accordance with ISO 5659-2, and heat release in EN-45545 is the
maximum average rate of heat emission (MAHRE) determined in
accordance with ISO 5660-1.
[0004] It is exceptionally challenging to develop materials that
meet stringent smoke density standards in addition to other
material requirements. It is particularly challenging to develop
materials that meet these requirements and that have good
mechanical properties (especially impact/scratch resistance) and
processability. Accordingly there remains a need in the art for
thermoplastic compositions that have excellent low smoke
properties. It would be a further advantage if the compositions
could be rendered low smoke without a significant properties
detrimental effect on one or more of material cost, processability,
and mechanical properties. It would be a still further advantage if
the materials could be readily thermoformed or injection
molded.
SUMMARY
[0005] A thermoplastic composition comprises, based on the total
weight of the thermoplastic composition, 70 to 95 wt % of a
polycarbonate copolymer comprising first repeating units and second
repeating units, wherein the first repeating units are not the same
as the second repeating units, and wherein the first repeating
units are bisphenol carbonate units of the formula
##STR00002##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12
alkoxy, p and q are each independently 0 to 4, and X.sup.a is a
single bond, --O--, --S--, --S(O)--, --S(O).sub.2--, --C(O)--, a
C.sub.1-11 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen or C.sub.1-10
alkyl, or a group of the formula --C(.dbd.R.sup.e)-- wherein
R.sup.e is a divalent C.sub.1-10 hydrocarbon group; and the second
repeating units comprise bisphenol carbonate units that are not the
same as the first repeating bisphenol carbonate units, siloxane
units, arylate ester units, or a combination of arylate ester units
and siloxane units; and 5 to 30 wt % of a polyetherimide based on
the weight of the composition, wherein an article molded from the
composition has a smoke density value of equal to or less than 300
as measured by ISO 5659-2 on a 3 mm thick plaque.
[0006] In another embodiment, the thermoplastic composition has a
multiaxial impact energy, as measured according to ISO 6603 on a
3.2 mm thick disc within 20% of the same composition without the
polyetherimide.
[0007] A method of manufacture of the thermoplastic compositions
comprises extruding or melt blending the components of the
thermoplastic compositions to form the thermoplastic
compositions.
[0008] In yet another embodiment, an article comprises the
thermoplastic compositions. The article can be a component of a
mass transportation vehicle, in particular a rail, aircraft, or
marine vehicle.
[0009] In still another embodiment, a method of manufacture of an
article comprises molding, extruding, or shaping the
above-described thermoplastic composition to form the article.
[0010] The above described and other features are exemplified by
the following detailed description and figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A description of the figures, which are meant to be
exemplary and not limiting, is provided in which:
[0012] FIG. 1 shows the effect of an increase in fractional
concentration (wt %) of a polyetherimide in an ITR-PC copolymer on
smoke density (Ds-4), indicating an interaction behavior;
[0013] FIG. 2 shows the effect of an increase in fractional
concentration (wt %) of a poly(phenylsulfone) (PPSU) in an ITR-PC
copolymer on smoke density (Ds-4), indicating the absence of
interaction behavior;
[0014] FIG. 3 shows the effect of an increase in fractional
concentration (wt %) of a polyetherimide in a PPPBP-BPA copolymer
on smoke density (Ds-4), indicating an interaction behavior;
[0015] FIG. 4 shows the effect of the increase in fractional
concentration (wt %) of a polyetherimide in a transparent
PC-siloxane copolymer on smoke density (Ds-4), indicating an
interaction behavior;
[0016] FIG. 5 shows the effect of the increase in fractional
concentration (wt %) of a polyetherimide in a homopolycarbonate on
smoke density (Ds-4), indicating an interaction behavior;
[0017] FIG. 6 the effect of the increase in fractional
concentration (wt %) of a polyetherimide in a combination of a
PC-siloxane copolymer and a homopolycarbonate on smoke density
(Ds-4), indicating an interaction behavior; and
[0018] FIG. 7 shows the effect of an increase in fractional
concentration (wt %) of a polyetherimide in a combination of an
ITR-PC copolymer and an ITR-PC-Si copolymer on smoke density
(Ds-4), indicating an interaction behavior.
[0019] The above described and other features are exemplified by
the following detailed description and Examples.
DETAILED DESCRIPTION
[0020] The inventors hereof have discovered that thermoplastic
compositions having very low smoke density as well as low heat
release can unexpectedly be obtained by combining certain
polycarbonate copolymers with a small amount of a polyetherimide.
In particular, the inventors have discovered that the combination
of the small amount of polyetherimide to certain polycarbonate
copolymers results in a non-linear decrease in the smoke density
(Ds-4) of the copolymers as determined in accordance with ISO
5659-2, in addition to decreasing the heat release (MAHRE) as
determined in accordance with ISO 5660-1. The results are
particularly surprising because only relatively small amounts of
polyetherimides are used, but the resulting smoke densities can be
as low as those obtained from polyetherimide alone. For example,
the thermoplastic composition can have a smoke density (Ds-4) of
less than 300 as determined in accordance with ISO 5659-2, despite
the much higher Ds-4 of the composition without polyetherimide. The
thermoplastic compositions can further have a heat release (MAHRE)
of less than 90 as determined in accordance with ISO 5660-1. With
this discovery, it is now possible to manufacture flame retardant
compositions having one or more of good impact properties, low
color, and high flow of polycarbonates, with the very low smoke
densities (Ds-4) determined according to ISO5659-2 on 3 mm thick
samples and low heat release (MAHRE) determined according to ISO
5660-1 on 3 mm thick samples, properties of polyetherimides.
[0021] Thus, the thermoplastic compositions can further have
excellent impact strength. The thermoplastic compositions can also
be formulated to have low melt viscosities, which renders them
suitable for injection molding. The compositions can further have
very low color, and in particular white compositions can be
obtained. Such compositions are especially useful in the
manufacture of large, low smoke, low heat release polycarbonate
sheets that can be used, for example, in the manufacture of
components in aircraft, train, marine, or other mass transportation
applications, as well as components in high occupancy, low
supervision structures.
[0022] In particular, the thermoplastic compositions contain a
polycarbonate copolymer comprising first carbonate units and second
units that are different from the first carbonate units. The first
carbonate units are bisphenol carbonate units derived from a
bisphenol-type compound. The second units can be bisphenol
carbonate units different from the first units, siloxane units,
arylate ester units, or a combination comprising at least one of
the foregoing types of units. For example, a combination of first
bisphenol carbonate units, arylate ester units, and siloxane units
can be present as the second units. The thermoplastic compositions
further contain 10 to 30 wt % of a polyetherimide, present in an
amount effective to provide a smoke density (Ds-4) of less than 300
as determined in accordance with ISO 5659-2 on 3 mm thick
plaques.
[0023] As used herein, the term "polycarbonate" and "polycarbonate
copolymer" refers to compounds having first repeating first units
that are bisphenol carbonate units of formula (1)
##STR00003##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12
alkoxy, p and q are each independently 0 to 4, and X.sup.a is a
bridging group between the two arylene groups, and is a single
bond, --O--, --S--, --S(O)--, --S(O).sub.2--, --C(O)--, a
C.sub.1-11 alkylidene of the formula --C(R.sup.c)(R.sup.d)--
wherein R.sup.c and R.sup.d are each independently hydrogen or
C.sub.1-10 alkyl, or a group of the formula --C(.dbd.R.sup.e)--
wherein R.sup.e is a divalent C.sub.1-10 hydrocarbon group.
Exemplary X.sup.a groups include methylene, ethylidene,
neopentylidene, and isopropylidene. The bridging group X.sup.a and
the carbonate oxygen atoms of each C.sub.6 arylene group can be
disposed ortho, meta, or para (specifically para) to each other on
the C.sub.6 arylene group.
[0024] In a specific embodiment, R.sup.a and R.sup.b are each
independently a C.sub.1-3 alkyl group, p and q are each
independently 0 to 1, and X.sup.a is a single bond, --O--,
--S(O)--, --S(O).sub.2--, --C(O)--, a C.sub.1-9 alkylidene of
formula --C(R.sup.c)(R.sup.d)-- wherein R.sup.c and R.sup.d are
each independently hydrogen or C.sub.1-8 alkyl, or a group of the
formula --C(.dbd.R.sup.e)-- wherein R.sup.e is a divalent C.sub.1-9
hydrocarbon group. In another specific embodiment, R.sup.a and
R.sup.b are each independently a methyl group, p and q are each
independently 0 to 1, and X.sup.a is a single bond, a C.sub.1-7
alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein R.sup.c and
R.sup.d are each independently hydrogen or C.sub.1-6 alkyl. In an
embodiment, p and q is each 1, and R.sup.a and R.sup.b are each a
C.sub.1-3 alkyl group, specifically methyl, disposed meta to the
oxygen on each ring. The bisphenol carbonate units (1) can be
derived from bisphenol-A, where p and q are both 0 and X.sup.a is
isopropylidene.
[0025] The polycarbonate units in the copolymers can be produced
from dihydroxy compounds of the formula (2)
HO--R.sup.1--OH (2)
wherein R.sup.1 is a bridging moiety. Thus, the bisphenol carbonate
units (1) are generally produced from the corresponding bisphenol
compounds of formula (3)
##STR00004##
wherein R.sup.a and R.sup.b, p and q, and X.sup.a are the same as
in formula (1).
[0026] Some illustrative examples of specific bisphenol compounds
that can be used to produce units (1) include
4,4'-dihydroxybiphenyl, bis(4-hydroxyphenyl)methane,
1,2-bis(4-hydroxyphenyl)ethane,
2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane,
1,2,2-bis(3-methyl-4-hydroxyphenyl)propane,
2,2-bis(3-ethyl-4-hydroxyphenyl)propane,
2,2-bis(3-n-propyl-4-hydroxyphenyl)propane,
2,2-bis(3-isopropyl-4-hydroxyphenyl)propane,
2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane,
2,2-bis(3-t-butyl-4-hydroxyphenyl)propane,
2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane,
2,2-bis(3-allyl-4-hydroxyphenyl)propane,
2,2-bis(3-methoxy-4-hydroxyphenyl)propane,
bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfide,
bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfone, or a
combination comprising at least one of the foregoing bisphenolic
compounds.
[0027] Specific examples of bisphenol compounds that can be used in
the production of bisphenol carbonate units (1) include
1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl) ethane,
2,2-bis(4-hydroxyphenyl) propane ("bisphenol-A" or "BPA"),
2,2-bis(4-hydroxyphenyl) butane, 2,2-bis(4-hydroxyphenyl) octane,
1,1-bis(4-hydroxyphenyl) propane, 1,1-bis(4-hydroxyphenyl)
n-butane, 2,2-bis(4-hydroxy-2-methylphenyl) propane,
1,1-bis(4-hydroxy-t-butylphenyl) propane, and combinations
comprising at least one of the foregoing bisphenol compounds.
[0028] As stated above, the polycarbonate copolymer further
comprises second repeating units. The second repeating units can be
bisphenol carbonate units (provided that they are different from
the bisphenol carbonate units (1)), arylate ester units, siloxane
units, or a combination of arylate ester units and siloxane units.
In particular, the second units can be bisphenol carbonate units of
formula (4)
##STR00005##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12 alkoxy, p and q are
each independently integers of 0 to 4, and X.sup.b is C.sub.2-32
bridging hydrocarbon group that is not the same as the X.sup.a in
the polycarbonate copolymer. The bridging group X.sup.b and the
carbonate oxygen atoms of each C.sub.6 arylene group can be
disposed ortho, meta, or para (specifically para) to each other on
the C.sub.6 arylene group.
[0029] In an embodiment, X.sup.b is a substituted or unsubstituted
C.sub.3-18 cycloalkylidene, a substituted or unsubstituted
C.sub.3-18 cycloalkylene, a substituted or unsubstituted
C.sub.12-25 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen, C.sub.1-24
alkyl, C.sub.4-12 cycloalkyl, C.sub.6-12 aryl, C.sub.7-12
arylalkylene, C.sub.1-12 heteroalkyl, or cyclic C.sub.7-12
heteroarylalkyl, or a group of the formula --C(.dbd.R.sup.e)--
wherein R.sup.e is a divalent C.sub.12-31 hydrocarbon group.
Exemplary X.sup.b groups include cyclohexylmethylidene, 1,1-ethene,
2-[2.2.1]-bicycloheptylidene, cyclohexylidene, cyclopentylidene,
cyclododecylidene, and adamantylidene.
[0030] In an embodiment, X.sup.b is a substituted or unsubstituted
C.sub.5-32 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen, C.sub.4-12
cycloalkyl, C.sub.6-12 aryl, C.sub.7-12 arylalkylene, C.sub.1-12
heteroalkyl, a substituted or unsubstituted group of the formula
--C(.dbd.R.sup.e)-- wherein R.sup.e is a divalent C.sub.12-31
hydrocarbyl, a substituted or unsubstituted C.sub.5-18
cycloalkylidene, a substituted or unsubstituted C.sub.5-18
cycloalkylene, a substituted or unsubstituted C.sub.3-18
heterocycloalkylidene, or a group of the formula
--B.sup.1-G-B.sup.2-- wherein B.sup.1 and B.sup.2 are the same or
different C.sub.1-6 alkylene group and G is a C.sub.3-12
cycloalkylidene group or a C.sub.6-16 arylene group.
[0031] For example, X.sup.b can be a substituted C.sub.3-18
heterocycloalkylidene of formula (4a)
##STR00006##
wherein R.sup.r, R.sup.p, R.sup.q, and R.sup.t are each
independently hydrogen, oxygen, or C.sub.1-12 organic groups; I is
a direct bond, a carbon, or a divalent oxygen, sulfur, or
--N(Z)-where Z is hydrogen, halogen, hydroxy, C.sub.1-12 alkyl,
C.sub.1-12 alkoxy, or C.sub.1-12 acyl; h is 0 to 2, j is 1 or 2, i
is an integer of 0 or 1, and k is an integer of 0 to 3, with the
proviso that at least two of R.sup.r, R.sup.p, R.sup.q, and R.sup.t
taken together are a fused cycloaliphatic, aromatic, or
heteroaromatic ring. It will be understood that where the fused
ring is aromatic, the ring as shown in formula (3) will have an
unsaturated carbon-carbon linkage where the ring is fused. When k
is one and i is 0, the ring as shown in formula (6) contains 4
carbon atoms, when k is 2, the ring contains 5 carbon atoms, and
when k is 3, the ring contains 6 carbon atoms. In an embodiment,
two adjacent groups (e.g., R.sup.q and R.sup.t taken together) form
an aromatic group, and in another embodiment, R.sup.q and R.sup.t
taken together form one aromatic group and R.sup.r and R.sup.p
taken together form a second aromatic group. When R.sup.q and
R.sup.t taken together form an aromatic group, R.sup.p can be a
double-bonded oxygen atom, i.e., a ketone.
[0032] Specific second bisphenol carbonate repeating units of this
type are phthalimidine carbonate units of formula (4b)
##STR00007##
wherein R.sup.a, R.sup.b, p, and q are as in formula (4), R.sup.3
is each independently a C.sub.1-6 alkyl group, j is 0 to 4, and
R.sup.4 is hydrogen, C.sub.1-6 alkyl, phenyl optionally substituted
with 1 to 5 C.sub.1-6 alkyl groups. In particular, the
phthalimidine carbonate units are of formula (4c)
##STR00008##
wherein R.sup.5 is hydrogen, phenyl optionally substituted with 1
to 5 C.sub.1-6 alkyl groups, or C.sub.1-6 alkyl. In an embodiment,
R.sup.5 is hydrogen, phenyl or methyl. Carbonate units (4a) wherein
R.sup.5 is phenyl can be derived from 2-phenyl-3,3'-bis(4-hydroxy
phenyl)phthalimidine (also known as N-phenyl phenolphthalein
bisphenol, or "PPPBP") (also known as
3,3-bis(4-hydroxyphenyl)-2-phenylisoindolin-1-one).
[0033] Other bisphenol carbonate repeating units of this type are
the isatin carbonate units of formula (4d) and (4e)
##STR00009##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, p and q are each independently 0 to 4, and R.sup.i is
C.sub.1-12 alkyl, phenyl, optionally substituted with 15 to
C.sub.1-10 alkyl, or benzyl optionally substituted with 1 to 5
C.sub.1-10 alkyl. In an embodiment, R.sup.a and R.sup.b are each
methyl, p and q are each independently 0 or 1, and R.sup.i is
C.sub.1-4 alkyl or phenyl.
[0034] Examples of bisphenol carbonate units (4) wherein X.sup.b is
a substituted or unsubstituted C.sub.3-18 cycloalkylidene include
the cyclohexylidene-bridged, alkyl-substituted bisphenol of formula
(4f)
##STR00010##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, R.sup.g is C.sub.1-12 alkyl, p and q are each independently
0 to 4, and t is 0 to 10. In a specific embodiment, at least one of
each of R.sup.a and R.sup.b are disposed meta to the
cyclohexylidene bridging group. In an embodiment, R.sup.a and
R.sup.b are each independently C.sub.1-4 alkyl, R.sup.g is
C.sub.1-4 alkyl, p and q are each 0 or 1, and t is 0 to 5. In
another specific embodiment, R.sup.a, R.sup.b, and R.sup.g are each
methyl, r and s are each 0 or 1, and t is 0 or 3, specifically
0.
[0035] Examples of other bisphenol carbonate units (4) wherein
X.sup.b is a substituted or unsubstituted C.sub.3-18
cycloalkylidene include adamantyl units (4g) and units (4h)
##STR00011##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, and p and q are each independently 1 to 4. In a specific
embodiment, at least one of each of R.sup.a and R.sup.b are
disposed meta to the cycloalkylidene bridging group. In an
embodiment, R.sup.a and R.sup.b are each independently C.sub.1-3
alkyl, and p and q are each 0 or 1. In another specific embodiment,
R.sup.a, R.sup.b are each methyl, p and q are each 0 or 1.
Carbonates containing units (4b) to (4h) are useful for making
polycarbonates with high glass transition temperatures (Tg) and
high heat distortion temperatures.
[0036] Bisphenol carbonate units (4) are generally produced from
the corresponding bisphenol compounds of formula (5)
##STR00012##
wherein R.sup.a, R.sup.b, p, q, and X.sup.b are the same as in
formula (4).
[0037] Specific examples of bisphenol compounds of formula (5)
include bis(4-hydroxyphenyl)diphenylmethane,
1,1-bis(4-hydroxy-t-butylphenyl) propane, 1,6-dihydroxynaphthalene,
2,6-dihydroxynaphthalene,
6,6'-dihydroxy-3,3,3',3'-tetramethylspiro(bis)indane
("spirobiindane bisphenol"), 2,6-dihydroxydibenzo-p-dioxin,
2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathiin,
2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran,
3,6-dihydroxydibenzothiophene, 2,7-dihydroxycarbazole, and
2,6-dihydroxythianthrene 3,3-bis(4-hydroxyphenyl) phthalimidine,
2-phenyl-3,3-bis(4-hydroxyphenyl) phthalimidine (PPPBP), and
1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (DMBPC). Combinations
comprising at least one of the foregoing dihydroxy compounds can
also be used.
[0038] The relative mole ratio of first bisphenol carbonate units
(1) and second bisphenol carbonate units (4) can vary from 99:1 to
1:99, depending on the desired characteristics of the thermoplastic
composition, including glass transition temperature ("Tg"), impact
strength, ductility, flow, and like considerations. For example,
the mole ratio of units (1): units (4) can be from 90:10 to 10:90,
from 80:20 to 20:80, from 70:30 to 30:70, or from 60:40 to 40:60.
When bisphenol carbonate units (1) units are derived from
bisphenol-A, the bisphenol-A units are generally present in an
amount from 50 to 99 mole %, based on the total moles of units in
the polycarbonate copolymer. For example, when bisphenol carbonate
units (1) units are derived from bisphenol-A, and bisphenol units
(4) are derived from PPPBP, the mole ration of units (1) to units
(4) can be from 99:1 to 50:50, or from 90:10 to 55:45.
[0039] Other carbonate units can be present in any of the
polycarbonate copolymers described herein, in relatively small
amounts, for example less than 20 mole %, less than 10 mole %, or
less than 5 mole %, based on the total moles of units in the
polycarbonate copolymer. The other carbonate units can be derived
from aliphatic or aromatic dihydroxy compounds having 1 to 32
carbon atoms, for example 1,6-dihydroxynaphthalene,
2,6-dihydroxynaphthalene,
6,6'-dihydroxy-3,3,3',3'-tetramethylspiro(bis)indane
("spirobiindane bisphenol"), 2,6-dihydroxydibenzo-p-dioxin,
2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathin,
2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran,
3,6-dihydroxydibenzothiophene, 2,7-dihydroxycarbazole, and
2,6-dihydroxythianthrene. A specific aromatic dihydroxy compound
includes the monoaryl dihydroxy compounds of formula (6)
##STR00013##
wherein each R.sup.h is independently a halogen atom, a C.sub.1-10
hydrocarbyl such as a C.sub.1-10 alkyl group, a halogen-substituted
C.sub.1-10 alkyl group, a C.sub.6-10 aryl group, or a
halogen-substituted C.sub.6-10 aryl group, and n is 0 to 4. The
halogen is usually bromine. In an embodiment, no halogens are
present. Specific monoaryl dihydroxy compounds (6) include
resorcinol, substituted resorcinol compounds such as 5-methyl
resorcinol, 5-ethyl resorcinol, 5-propyl resorcinol, 5-butyl
resorcinol, 5-t-butyl resorcinol, 5-phenyl resorcinol, 5-cumyl
resorcinol, 2,4,5,6-tetrafluoro resorcinol, 2,4,5,6-tetrabromo
resorcinol, and the like; catechol; hydroquinone; and substituted
hydroquinones such as 2-methyl hydroquinone, 2-ethyl hydroquinone,
2-propyl hydroquinone, 2-butyl hydroquinone, 2-t-butyl
hydroquinone, 2-phenyl hydroquinone, 2-cumyl hydroquinone,
2,3,5,6-tetramethyl hydroquinone, 2,3,5,6-tetra-t-butyl
hydroquinone, 2,3,5,6-tetrafluoro hydroquinone, 2,3,5,6-tetrabromo
hydroquinone. A combination comprising at least one of the
foregoing aromatic dihydroxy compounds can be used. In an
embodiment, the polycarbonate copolymer comprises carbonate units
of formulas (1) and (4), and less than 10 mole % of units derived
from monoaryl dihydroxy compounds (6), i.e., monoaryl carbonate
units of the formula (6a)
##STR00014##
wherein each R.sup.h is independently a halogen or C.sub.1-10
hydrocarbon group, and n is 0 to 4. Specifically, each R.sup.h is
independently a C.sub.1-3 alkyl group, and n is 0 to 1, or n is 0.
In another embodiment, no carbonate units other than units of
formulas (1) and (4) are present in the polycarbonate
copolymer.
[0040] Polycarbonates can be manufactured by processes such as
interfacial polymerization and melt polymerization. Although the
reaction conditions for interfacial polymerization can vary, an
exemplary process generally involves dissolving or dispersing a
dihydric phenol reactant in aqueous caustic soda or potash, adding
the resulting mixture to a water-immiscible solvent medium, and
contacting the reactants with a carbonate precursor in the presence
of a catalyst such as, for example, a tertiary amine or a phase
transfer catalyst, under controlled pH conditions, e.g., 8 to 10.
The water immiscible solvent can be, for example, methylene
chloride, 1,2-dichloroethane, chlorobenzene, toluene, and the
like.
[0041] Exemplary carbonate precursors include a carbonyl halide
such as carbonyl bromide or carbonyl chloride, or a haloformate
such as a bishaloformates of a dihydric phenol (e.g., the
bischloroformates of bisphenol A, hydroquinone, or the like) or a
glycol (e.g., the bishaloformate of ethylene glycol, neopentyl
glycol, polyethylene glycol, or the like). Combinations comprising
at least one of the foregoing types of carbonate precursors can
also be used. In an embodiment, an interfacial polymerization
reaction to form carbonate linkages uses phosgene as a carbonate
precursor, and is referred to as a phosgenation reaction.
[0042] Among tertiary amines that can be used are aliphatic
tertiary amines such as triethylamine and tributylamine,
cycloaliphatic tertiary amines such as N,N-diethyl-cyclohexylamine,
and aromatic tertiary amines such as N,N-dimethylaniline. Among the
phase transfer catalysts that can be used are catalysts of the
formula (R.sup.3).sub.4Q.sup.+X.sup.-, wherein each R.sub.3 is the
same or different, and is a C.sub.1-10 alkyl group; Q is a nitrogen
or phosphorus atom; and X is a halogen atom or a C.sub.1-8 alkoxy
group or C.sub.6-18 aryloxy group. Exemplary phase transfer
catalysts include (CH.sub.3(CH.sub.2).sub.3).sub.4N.sup.+X.sup.-,
(CH.sub.3(CH.sub.2).sub.3).sub.4P.sup.+X.sup.-,
(CH.sub.3(CH.sub.2).sub.5).sub.4N.sup.+X.sup.-,
(CH.sub.3(CH.sub.2).sub.6).sub.4N.sup.+X.sup.-,
(CH.sub.3(CH.sub.2).sub.4).sub.4N.sup.+X.sup.-,
CH.sub.3(CH.sub.3(CH.sub.2).sub.3).sub.3N.sup.+X.sup.-, and
CH.sub.3(CH.sub.3(CH.sub.2).sub.2).sub.3N.sup.+X.sup.-, wherein X
is Cl.sup.-, Br.sup.-, a C.sub.1-8 alkoxy group or a C.sub.6-18
aryloxy group. An effective amount of a phase transfer catalyst can
be 0.1 to 10 wt %, or 0.5 to 2 wt %, each based on the weight of
bisphenol in the phosgenation mixture.
[0043] Alternatively, melt processes can be used to make the
polycarbonates. Melt polymerization may be conducted as a batch
process or as a continuous process. In either case, the melt
polymerization conditions used may comprise two or more distinct
reaction stages, for example, a first reaction stage in which the
starting dihydroxy aromatic compound and diaryl carbonate are
converted into an oligomeric polycarbonate and a second reaction
stage wherein the oligomeric polycarbonate formed in the first
reaction stage is converted to high molecular weight polycarbonate.
Such "staged" polymerization reaction conditions are especially
suitable for use in continuous polymerization systems wherein the
starting monomers are oligomerized in a first reaction vessel and
the oligomeric polycarbonate formed therein is continuously
transferred to one or more downstream reactors in which the
oligomeric polycarbonate is converted to high molecular weight
polycarbonate. Typically, in the oligomerization stage the
oligomeric polycarbonate produced has a number average molecular
weight of about 1,000 to about 7,500 Daltons. In one or more
subsequent polymerization stages the number average molecular
weight (Mn) of the polycarbonate is increased to between about
8,000 and about 25,000 Daltons (using polycarbonate standard).
[0044] The term "melt polymerization conditions" is understood to
mean those conditions necessary to effect reaction between a
dihydroxy aromatic compound and a diaryl carbonate in the presence
of a transesterification catalyst. Typically, solvents are not used
in the process, and the reactants dihydroxy aromatic compound and
the diaryl carbonate are in a molten state. The reaction
temperature can be about 100.degree. C. to about 350.degree. C.,
specifically about 180.degree. C. to about 310.degree. C. The
pressure may be at atmospheric pressure, supra-atmospheric
pressure, or a range of pressures from atmospheric pressure to
about 15 torr in the initial stages of the reaction, and at a
reduced pressure at later stages, for example about 0.2 to about 15
torr. The reaction time is generally about 0.1 hours to about 10
hours.
[0045] The diaryl carbonate ester can be diphenyl carbonate, or an
activated diphenyl carbonate having electron-withdrawing
substituents on the aryl groups, such as
bis(4-nitrophenyl)carbonate, bis(2-chlorophenyl)carbonate,
bis(4-chlorophenyl)carbonate, bis(methyl salicyl)carbonate,
bis(4-methylcarboxylphenyl) carbonate, bis(2-acetylphenyl)
carboxylate, bis(4-acetylphenyl) carboxylate, or a combination
comprising at least one of the foregoing.
[0046] Catalysts used in the melt polymerization of polycarbonates
can include alpha or beta catalysts. Beta catalysts are typically
volatile and degrade at elevated temperatures. Beta catalysts are
therefore preferred for use at early low-temperature polymerization
stages. Alpha catalysts are typically more thermally stable and
less volatile than beta catalysts.
[0047] The alpha catalyst can comprise a source of alkali or
alkaline earth ions. The sources of these ions include alkali metal
hydroxides such as lithium hydroxide, sodium hydroxide, and
potassium hydroxide, as well as alkaline earth hydroxides such as
magnesium hydroxide and calcium hydroxide. Other possible sources
of alkali and alkaline earth metal ions include the corresponding
salts of carboxylic acids (such as sodium acetate) and derivatives
of ethylene diamine tetraacetic acid (EDTA) (such as EDTA
tetrasodium salt, and EDTA magnesium disodium salt). Other alpha
transesterification catalysts include alkali or alkaline earth
metal salts of a non-volatile inorganic acid such as
NaH.sub.2PO.sub.3, NaH.sub.2PO.sub.4, Na.sub.2HPO.sub.3,
KH.sub.2PO.sub.4, CsH.sub.2PO.sub.4, Cs.sub.2HPO.sub.4, and the
like, or mixed salts of phosphoric acid, such as NaKHPO.sub.4,
CsNaHPO.sub.4, CsKHPO.sub.4, and the like. Combinations comprising
at least one of any of the foregoing catalysts can be used.
[0048] Possible beta catalysts can comprise a quaternary ammonium
compound, a quaternary phosphonium compound, or a combination
comprising at least one of the foregoing. The quaternary ammonium
compound can be a compound of the structure
(R.sup.4).sub.4N.sup.+X.sup.-, wherein each R.sup.4 is the same or
different, and is a C.sub.1-20 alkyl group, a C.sub.4-20 cycloalkyl
group, or a C.sub.4-20 aryl group; and X.sup.- is an organic or
inorganic anion, for example a hydroxide, halide, carboxylate,
sulfonate, sulfate, formate, carbonate, or bicarbonate. Examples of
organic quaternary ammonium compounds include tetramethyl ammonium
hydroxide, tetrabutyl ammonium hydroxide, tetramethyl ammonium
acetate, tetramethyl ammonium formate, tetrabutyl ammonium acetate,
and combinations comprising at least one of the foregoing.
Tetramethyl ammonium hydroxide is often used. The quaternary
phosphonium compound can be a compound of the structure
(R.sup.5).sub.4P.sup.+X.sup.-, wherein each R.sup.5 is the same or
different, and is a C.sub.1-20 alkyl group, a C.sub.4-20 cycloalkyl
group, or a C.sub.4-20 aryl group; and X.sup.- is an organic or
inorganic anion, for example a hydroxide, halide, carboxylate,
sulfonate, sulfate, formate, carbonate, or bicarbonate. Where
X.sup.- is a polyvalent anion such as carbonate or sulfate it is
understood that the positive and negative charges in the quaternary
ammonium and phosphonium structures are properly balanced. For
example, where R.sup.20-R.sup.23 are each methyl groups and X.sup.-
is carbonate, it is understood that X.sup.- represents
2(CO.sub.3.sup.-2). Examples of organic quaternary phosphonium
compounds include tetramethyl phosphonium hydroxide, tetramethyl
phosphonium acetate, tetramethyl phosphonium formate, tetrabutyl
phosphonium hydroxide, tetrabutyl phosphonium acetate (TBPA),
tetraphenyl phosphonium acetate, tetraphenyl phosphonium phenoxide,
and combinations comprising at least one of the foregoing. TBPA is
often used.
[0049] The amount of alpha and beta catalyst used can be based upon
the total number of moles of dihydroxy compound used in the
polymerization reaction. When referring to the ratio of beta
catalyst, for example a phosphonium salt, to all dihydroxy
compounds used in the polymerization reaction, it is convenient to
refer to moles of phosphonium salt per mole of the dihydroxy
compound, meaning the number of moles of phosphonium salt divided
by the sum of the moles of each individual dihydroxy compound
present in the reaction mixture. The alpha catalyst can be used in
an amount sufficient to provide 1.times.10.sup.-2 to
1.times.10.sup.-8 moles, specifically, 1.times.10.sup.-4 to
1.times.10.sup.-7 moles of metal per mole of the dihydroxy
compounds used. The amount of beta catalyst (e.g., organic ammonium
or phosphonium salts) can be 1.times.10.sup.-2 to
1.times.10.sup.-5, specifically 1.times.10.sup.-3 to
1.times.10.sup.-4 moles per total mole of the dihydroxy compounds
in the reaction mixture.
[0050] Branched polycarbonate blocks can be prepared by adding a
branching agent during polymerization. These branching agents
include polyfunctional organic compounds containing at least three
functional groups selected from hydroxyl, carboxyl, carboxylic
anhydride, haloformyl, and mixtures of the foregoing functional
groups. Specific examples include trimellitic acid, trimellitic
anhydride, trimellitic trichloride, tris-p-hydroxy phenyl ethane,
isatin-bis-phenol, tris-phenol TC
(1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), tris-phenol PA
(4(4(1,1-bis(p-hydroxyphenyl)-ethyl) alpha, alpha-dimethyl
benzyl)phenol), 4-chloroformyl phthalic anhydride, trimesic acid,
and benzophenone tetracarboxylic acid. The branching agents can be
added at a level of about 0.05 to about 5 wt %. Combinations
comprising linear polycarbonates and branched polycarbonates can be
used.
[0051] All types of polycarbonate end groups are contemplated as
being useful in the polycarbonate composition, provided that such
end groups do not significantly adversely affect desired properties
of the compositions. A chain stopper (also referred to as a capping
agent) can be included during polymerization. The chain stopper
limits molecular weight growth rate, and so controls molecular
weight in the polycarbonate. Exemplary chain stoppers include
certain mono-phenolic compounds, mono-carboxylic acid chlorides,
and/or mono-chloroformates. Mono-phenolic chain stoppers are
exemplified by monocyclic phenols such as phenol and
C.sub.1-C.sub.22 alkyl-substituted phenols such as p-cumyl-phenol,
resorcinol monobenzoate, and p- and tertiary-butyl phenol; and
monoethers of diphenols, such as p-methoxyphenol. Alkyl-substituted
phenols with branched chain alkyl substituents having 8 to 9 carbon
atom can be specifically mentioned. Certain mono-phenolic UV
absorbers can also be used as a capping agent, for example
4-substituted-2-hydroxybenzophenones and their derivatives, aryl
salicylates, monoesters of diphenols such as resorcinol
monobenzoate, 2-(2-hydroxyaryl)-benzotriazoles and their
derivatives, 2-(2-hydroxyaryl)-1,3,5-triazines and their
derivatives, and the like. Mono-carboxylic acid chlorides can also
be used as chain stoppers. These include monocyclic,
mono-carboxylic acid chlorides such as benzoyl chloride,
C.sub.1-C.sub.22 alkyl-substituted benzoyl chloride, toluoyl
chloride, halogen-substituted benzoyl chloride, bromobenzoyl
chloride, cinnamoyl chloride, 4-nadimidobenzoyl chloride, and
combinations thereof; polycyclic, mono-carboxylic acid chlorides
such as trimellitic anhydride chloride, and naphthoyl chloride; and
combinations of monocyclic and polycyclic mono-carboxylic acid
chlorides. Chlorides of aliphatic monocarboxylic acids with less
than or equal to about 22 carbon atoms are useful. Functionalized
chlorides of aliphatic monocarboxylic acids, such as acryloyl
chloride and methacryoyl chloride, are also useful. Also useful are
mono-chloroformates including monocyclic, mono-chloroformates, such
as phenyl chloroformate, alkyl-substituted phenyl chloroformate,
p-cumyl phenyl chloroformate, toluene chloroformate, and
combinations thereof.
[0052] The polycarbonate copolymers comprising carbonate units (1)
and carbonate units (4) can have an intrinsic viscosity, as
determined in chloroform at 25.degree. C., of about 0.3 to about
1.5 deciliters per gram (dl/gm), specifically about 0.45 to about
1.0 dl/gm. The polycarbonate copolymers can have a weight average
molecular weight of about 10,000 to about 200,000 g/mol,
specifically about 20,000 to about 100,000 g/mol, as measured by
gel permeation chromatography (GPC), using a crosslinked
styrene-divinylbenzene column and calibrated to polycarbonate
references. GPC samples are prepared at a concentration of about 1
mg per ml, and are eluted at a flow rate of about 1.5 ml per
minute.
[0053] In another embodiment the polycarbonate copolymers contain
the first repeating bisphenol carbonate units (1), and repeating
arylate ester units of formula (7)
##STR00015##
wherein Ar.sup.1 is a C.sub.6-32 hydrocarbyl group containing at
least one aromatic group, e.g., a phenyl, naphthalene, anthracene,
or the like. In an embodiment, Ar.sup.1 is derived from an aromatic
bisphenol as described above in connection with units (1) and (4),
a monoaryl dihydroxy compound (6), or a combination comprising
different bisphenol or monoaryl dihydroxy compounds. Thus, arylate
ester units (7) can be derived by reaction of isophthalic acid,
terephthalic acid, or a combination thereof (referred to herein as
a "phthalic acid"), with any of the aromatic bisphenols described
above, a monoaryl dihydroxy compound (6), or a combination thereof.
The molar ratio of isophthalate to terephthalate can be 1:99 to
99:1, or 80:20 to 20:80, or 60:40 to 40:60.
[0054] The polycarbonate copolymers comprising first bisphenol
carbonate units (1) and arylate ester units (7) can be alternating
or block copolymers of formula (8)
##STR00016##
wherein R.sup.1 and Ar.sup.1 are as defined in formulas (1) and
(7), respectively.
[0055] In general, the copolymers are block copolymers containing
carbonate blocks and ester blocks. The weight ratio of total ester
units to total carbonate units in the copolymers can vary broadly,
for example from 99:1 to 1:99, or from 95:5 to 5:95, specifically
from 90:10 to 10:90, or more specifically from 90:10 to 50:50,
depending on the desired properties of the thermoplastic
composition. The molar ratio of isophthalate to terephthalate in
the ester units of the copolymers can also vary broadly, for
example from 0:100 to 100:0, or from 92:8 to 8:92, more
specifically from 98:2 to 45:55, depending on the desired
properties of the thermoplastic composition. For example, the
weight ratio of total ester units to total carbonate can be 99:1 to
40:60, or 90:10 to 50:40, wherein the molar ratio of isophthalate
to terephthalate is from 99:1 to 40:50, more specifically 98:2 to
45:55, depending on the desired properties of the thermoplastic
composition.
[0056] Additional carbonate units derived from the dihydroxy
compound used to form the arylate ester units (7) can also be
present as described above, for example in amounts of less than 20
mole %, less than 10 mole %, or less than 5 mole %, based on the
total moles of units in the polycarbonate copolymer. It is also
possible to have additional arylate ester units present derived
from reaction of the phthalic acid with the dihydroxy compound used
to form the carbonate units, for example in amounts of less than 20
mole %, less than 10 mole %, less than 5 mole %, or less than 1
mole % based on the total moles of units in the copolymer. In an
embodiment, the combination of such additional carbonate units and
such additional arylate ester units are present in an amount of
less than 20 mole %, less than 10 mole %, less than 5 mole %, or
less than 1 mole % based on the total moles of units in the
copolymer.
[0057] A specific poly(carbonate-arylate ester) is a
poly(carbonate)-co-(bisphenol arylate ester) comprising carbonate
units (1), specifically bisphenol carbonate units, even more
specifically bisphenol-A carbonate units and repeating bisphenol
arylate ester units. Bisphenol arylate units comprise residues of
phthalic acid and a bisphenol, for example a bisphenol (2). In an
embodiment the bisphenol arylate ester units are of formula
(7a)
##STR00017##
wherein R.sup.a and R.sup.b are each independently C.sub.1-12
alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12
alkoxy, p and q are each independently 0 to 4, and X.sup.a is a
bridging group between the two arylene groups, and is a single
bond, --O--, --S--, --S(O)--, --S(O).sub.2--, --C(O)--, a
C.sub.1-11 alkylidene of the formula --C(R.sup.c)(R.sup.d)--
wherein R.sup.c and R.sup.d are each independently hydrogen or
C.sub.1-10 alkyl, or a group of the formula --C(.dbd.R.sup.e)--
wherein R.sup.e is a divalent C.sub.1-10 hydrocarbon group. In an
embodiment, p and q is each 1, and R.sup.a and R.sup.b are each a
C.sub.1-3 alkyl group, specifically methyl, disposed meta to the
oxygen on each ring. The bisphenol can be bisphenol-A, where p and
q are both 0 and X.sup.a is isopropylidene.
[0058] In a specific embodiment, the polycarbonate copolymer is a
poly(bisphenol-A-phthalate-ester)-co-(bisphenol-A carbonate) of
formula (8a)
##STR00018##
wherein x and y represent the weight percent of arylate-bisphenol-A
ester units and bisphenol-A carbonate units, respectively.
Generally, the units are present as blocks. In an embodiment, the
weight percent of ester units y to carbonate units y in the
copolymers is 50:50 to 99:1, or 55:45 to 90:10, or 75:25 to 95:5.
Copolymers of formula (8a) comprising 35 to 45 wt % of carbonate
units and 55 to 65 wt % of ester units, wherein the ester units
have a molar ratio of isophthalate to terephthalate of 45:55 to
55:45 are often referred to as poly(carbonate-ester)s (PCE) and
copolymers comprising 15 to 25 wt % of carbonate units and 75 to 85
wt % of ester units having a molar ratio of isophthalate to
terephthalate from 98:2 to 88:12 are often referred to as
poly(phthalate-carbonate)s (PPC).
[0059] In another embodiment, a specific polycarbonate copolymer
contains carbonate units (1) and repeating monoaryl-arylate ester
units of formula (7b)
##STR00019##
wherein each R.sup.h is independently a halogen atom, a C.sub.1-10
hydrocarbyl such as a C.sub.1-10 alkyl group, a halogen-substituted
C.sub.1-10 alkyl group, a C.sub.6-10 aryl group, or a
halogen-substituted C.sub.6-10 aryl group, and n is 0 to 4.
Specifically, each R.sup.h is independently a C.sub.1-4 alkyl, and
n is 0 to 3, 0 to 1, or 0. These poly(carbonate)-co-(monoaryl
arylate ester) copolymers are of formula (8b)
##STR00020##
wherein R.sup.1 is as defined in formula (1) and R.sup.h, and n are
as defined in formula (7b), and the mole ratio of x:m is 99:1 to
1:99, specifically 80:20 to 20:80, or 60:40 to 40:60.
[0060] Specifically, the monoaryl-arylate ester unit (7b) is
derived from the reaction of a combination of isophthalic and
terephthalic diacids (or derivatives thereof) with resorcinol (or
reactive derivatives thereof) to provide
isophthalate-terephthalate-resorcinol ("ITR" ester units) of
formula (7c)
##STR00021##
wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50,
or still more specifically 10 to 30. In an embodiment, the ITR
ester units are present in the polycarbonate copolymer in an amount
greater than or equal to 95 mol %, specifically greater than or
equal to 99 mol %, and still more specifically greater than or
equal to 99.5 mol % based on the total moles of ester units in the
copolymer. Such (isophthalate-terephthalate-resorcinol)-carbonate
copolymers ("ITR-PC") can possess many desired features, including
toughness, transparency, and weatherability. ITR-PC copolymers can
also have desirable thermal flow properties. In addition, ITR-PC
copolymers can be readily manufactured on a commercial scale using
interfacial polymerization techniques, which allow synthetic
flexibility and composition specificity in the synthesis of the
ITR-PC copolymers. Certain ITR-PC copolymers have inherently low
smoke density properties. In these copolymers, the addition of the
polyetherimides significantly reduces the heat release of the
copolymers.
[0061] A specific example of a poly(carbonate)-co-(monoaryl arylate
ester) is a poly(bisphenol-A
carbonate)-co-(isophthalate-terephthalate-resorcinol ester) of
formula (8c)
##STR00022##
wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50,
or still more specifically 10 to 30, and the mole ratio of x:n is
99:1 to 1:99, specifically 90:10 to 10:90. The ITR ester units are
present in the poly(carbonate-arylate ester) copolymer in an amount
greater than or equal to 95 mol %, specifically greater than or
equal to 99 mol %, and still more specifically greater than or
equal to 99.5 mol % based on the total moles of ester units. Other
carbonate units, other ester units, or a combination thereof can be
present, in a total amount of 1 to 20 mole % based on the total
moles of units in the copolymers, for example resorcinol carbonate
units of the formula
##STR00023##
and bisphenol-A phthalate ester units of the formula
##STR00024##
In an embodiment, poly(bisphenol-A
carbonate)-co-(isophthalate-terephthalate-resorcinol ester) (8c)
comprises 1 to 20 mol % of bisphenol-A carbonate units, 60-98 mol %
of isophthalic acid-terephthalic acid-resorcinol ester units, and
optionally 1 to 20 mol % of resorcinol carbonate units, isophthalic
acid-terephthalic acid-bisphenol-A phthalate ester units, or a
combination thereof.
[0062] The polycarbonate copolymers comprising arylate ester units
are generally prepared from polyester blocks. The polyester blocks
can also be prepared by interfacial polymerization. Rather than
utilizing the dicarboxylic acid or diol per se, the reactive
derivatives of the acid or diol, such as the corresponding acid
halides, in particular the acid dichlorides and the acid dibromides
can be used. Thus, for example instead of using isophthalic acid,
terephthalic acid, or a combination comprising at least one of the
foregoing acids, isophthaloyl dichloride, terephthaloyl dichloride,
or a combination comprising at least one of the foregoing
dichlorides can be used. The polyesters can also be obtained by
melt-process condensation as described above, by solution phase
condensation, or by transesterification polymerization wherein, for
example, a dialkyl ester such as dimethyl terephthalate can be
transesterified with the dihydroxy reactant using acid catalysis,
to generate the polyester blocks. Branched polyester blocks, in
which a branching agent, for example, a glycol having three or more
hydroxyl groups or a trifunctional or multifunctional carboxylic
acid has been incorporated, can be used. Furthermore, it can be
desirable to have various concentrations of acid and hydroxyl end
groups on the polyester blocks, depending on the ultimate end use
of the composition.
[0063] The polycarbonate copolymers comprising arylate ester units
can have an M.sub.W of 2,000 to 100,000 g/mol, specifically 3,000
to 75,000 g/mol, more specifically 4,000 to 50,000 g/mol, more
specifically 5,000 to 35,000 g/mol, and still more specifically
17,000 to 30,000 g/mol. Molecular weight determinations are
performed using GPC using a cross linked styrene-divinyl benzene
column, at a sample concentration of 1 milligram per milliliter,
and as calibrated with polycarbonate standards. Samples are eluted
at a flow rate of about 1.0 ml/min with methylene chloride as the
eluent.
[0064] In another embodiment, the polycarbonate copolymers are
"PC-siloxane" copolymers that contain bisphenol carbonate units (1)
and repeating siloxane units (also known as "diorganosiloxane
units"). The polysiloxane units are of formula (9)
##STR00025##
wherein each R is independently a C.sub.1-13 monovalent hydrocarbyl
group. For example, each R can independently be a C.sub.1-13 alkyl
group, C.sub.1-13 alkoxy group, C.sub.2-13 alkenyl group,
C.sub.2-13 alkenyloxy group, C.sub.3-6 cycloalkyl group, C.sub.3-6
cycloalkoxy group, C.sub.6-14 aryl group, C.sub.6-10 aryloxy group,
C.sub.7-13 arylalkyl group, C.sub.7-13 arylalkoxy group, C.sub.7-13
alkylaryl group, or C.sub.7-13 alkylaryloxy group. The foregoing
groups can be fully or partially halogenated with fluorine,
chlorine, bromine, or iodine, or a combination thereof. In an
embodiment no halogens are present. Combinations of the foregoing R
groups can be used in the same copolymer. In an embodiment, the
polysiloxane comprises R groups that have minimal hydrocarbon
content. In a specific embodiment, an R group with a minimal
hydrocarbon content is a methyl group.
[0065] The average value of E in formula (9) can vary widely
depending on the type and relative amount of each component in the
thermoplastic composition, whether the polymer is linear, branched
or a graft copolymer, the desired properties of the composition,
and like considerations. In an embodiment, E has an average value
of 2 to 500, 2 to 200, or 5 to 100, 10 to 100, 10 to 80, 2 to 30,
or 30 to 80. In an embodiment E has an average value of 16 to 50,
more specifically 20 to 45, and even more specifically 25 to 45. In
another embodiment, E has an average value of 4 to 50, 4 to 15,
specifically 5 to 15, more specifically 6 to 15, and still more
specifically 7 to 10. In an embodiment, the polysiloxane units are
structural units of formula (9a)
##STR00026##
wherein E is as defined above; each R can independently be the same
or different, and is as defined above; and each Ar can
independently be the same or different, and is a substituted or
unsubstituted C.sub.6-30 compound containing an aromatic group,
wherein the bonds are directly connected to the aromatic moiety.
The Ar groups in formula (9a) can be derived from a C.sub.6-30
dihydroxy aromatic compound, for example a bisphenol compound as
described above or a monoaryl dihydroxy compound (6) above.
Combinations comprising at least one of the foregoing dihydroxy
aromatic compounds can also be used. Exemplary dihydroxy aromatic
compounds are resorcinol (i.e., 1,3-dihydroxybenzene),
4-methyl-1,3-dihydroxybenzene, 5-methyl-1,3-dihydroxybenzene,
4,6-dimethyl-1,3-dihydroxybenzene, 1,4-dihydroxybenzene,
1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl) ethane,
2,2-bis(4-hydroxyphenyl) propane, 2,2-bis(4-hydroxyphenyl) butane,
2,2-bis(4-hydroxyphenyl) octane, 1,1-bis(4-hydroxyphenyl) propane,
1,1-bis(4-hydroxyphenyl) n-butane,
2,2-bis(4-hydroxy-1-methylphenyl) propane, 1,1-bis(4-hydroxyphenyl)
cyclohexane, bis(4-hydroxyphenyl sulfide), and
1,1-bis(4-hydroxy-t-butylphenyl) propane. Combinations comprising
at least one of the foregoing dihydroxy compounds can also be used.
In an embodiment, the dihydroxy aromatic compound is unsubstituted,
or is does not contain non-aromatic hydrocarbyl substituents such
as alkyl, alkoxy, or alkylene substituents.
[0066] In a specific embodiment, where Ar is derived from
resorcinol, the polysiloxane units are of the formula (9a-1)
##STR00027##
or, where Ar is derived from bisphenol-A, the polysiloxane has the
formula (9a-2)
##STR00028##
or a combination comprising at least one of the foregoing can be
used, wherein E has an average value as described above,
specifically an average value of 2 to 200.
[0067] In another embodiment, polydiorganosiloxane units are units
of formula (9b)
##STR00029##
wherein R and E are as described for formula (9), and each R.sup.2
is independently a divalent C.sub.1-30 alkylene or C.sub.7-30
arylene-alkylene. In a specific embodiment, where R.sup.2 is
C.sub.7-30 arylene-alkylene, the polydiorganosiloxane units are of
formula (9b-1)
##STR00030##
wherein R and E are as defined for formula (9), and each R.sup.3 is
independently a divalent C.sub.2-8 aliphatic group. Each M in
formula (25) can be the same or different, and can be a halogen,
cyano, nitro, C.sub.1-8 alkylthio, C.sub.1-8 alkyl, C.sub.1-8
alkoxy, C.sub.2-8 alkenyl, C.sub.2-8 alkenyloxy group, C.sub.3-8
cycloalkyl, C.sub.3-8 cycloalkoxy, C.sub.6-10 aryl, C.sub.6-10
aryloxy, C.sub.7-12 arylalkyl, C.sub.7-12 arylalkoxy, C.sub.7-12
alkylaryl, or C.sub.7-12 alkylaryloxy, wherein each n is
independently 0, 1, 2, 3, or 4. In an embodiment, M is bromo or
chloro, an alkyl group such as methyl, ethyl, or propyl, an alkoxy
group such as methoxy, ethoxy, or propoxy, or an aryl group such as
phenyl, chlorophenyl, or tolyl; R.sup.3 is a dimethylene,
trimethylene or tetramethylene group; and R is a C.sub.1-8 alkyl,
haloalkyl such as trifluoropropyl, cyanoalkyl, or aryl such as
phenyl, chlorophenyl or tolyl. In another embodiment, R is methyl,
or a combination of methyl and trifluoropropyl, or a combination of
methyl and phenyl. In still another embodiment, M is methoxy, n is
0 or 1, R.sup.3 is a divalent C.sub.1-3 aliphatic group, and R is
methyl.
[0068] In a specific embodiment, the polysiloxane units are of
formula (9b-2)
##STR00031##
where E has an average value as described above, specifically 5 to
100, 2 to 30, or 30 to 80. In another specific embodiment, the
polysiloxane units are of formula (9b-3)
##STR00032##
where E has an average value as defined above, specifically an
average value of 5 to 100, 2 to 30, or 30 to 80.
[0069] The relative amount of carbonate units (1) and polysiloxane
units (9) in the PC-siloxane copolymers depends on the desired
properties of the thermoplastic composition, such as impact, smoke
density, heat release, and melt viscosity. In particular the
polycarbonate copolymer is selected to have an average value of E
that provides good impact and/or transparency properties, as well
as to provide the desired weight percent of siloxane units in the
thermoplastic composition. For example, the polycarbonate
copolymers can comprise siloxane units in an amount of 0.3 to 30
weight percent (wt %), specifically 0.5 to 25 wt %, or 0.5 to 15 wt
%, based on the total weight of the polymers in the thermoplastic
composition, with the proviso that the siloxane units are provided
by polysiloxane units covalently bonded in the polymer backbone of
the polycarbonate copolymer.
[0070] A specific PC-siloxane comprises first carbonate units (1)
derived from bisphenol-A, and second repeating siloxane units
(9b-2), (9b-3), or a combination thereof. This polycarbonate
copolymer can comprise the siloxane units in an amount of 0.1 to 25
weight percent (wt %), 0.2 to 10 wt %, 0.2 to 6 wt % 0.2 to 5 wt %,
or 0.25 to 2 wt %, based on the total weight of the polycarbonate
copolymer, with the proviso that the siloxane units are covalently
bound to the polymer backbone of the polycarbonate copolymer. In an
embodiment, the remaining units are bisphenol units (1).
[0071] Methods for the manufacture of the PC-siloxane copolymers
are known. The PC-siloxane copolymers can have an intrinsic
viscosity, as determined in chloroform at 25.degree. C., of 0.3 to
1.5 deciliters per gram (dl/g), specifically 0.45 to 1.0 dl/g. The
PC-siloxane copolymers can have a weight average molecular weight
(M.sub.w) of 10,000 to 100,000 g/mol, as measured by gel permeation
chromatography (GPC) using a cross linked styrene-divinyl benzene
column, at a sample concentration of 1 milligram per milliliter,
and as calibrated with polycarbonate standards.
[0072] In still another embodiment, the polycarbonate copolymers
comprise bisphenol carbonate units (1) and second units comprising
a combination of the bisphenol carbonate units (4), the ester units
(7), and the polysiloxane units (9). For example, a polycarbonate
copolymer can comprise first bisphenol carbonate units (1), second
bisphenol carbonate units (4) different from the first carbonate
units, and either ester units (7) or siloxane units (9). In a
specific embodiment the polycarbonate copolymer comprises first
bisphenol carbonate units (1), arylate ester units (7), and
siloxane units (9). Still more specifically, the polycarbonate
copolymers comprise comprises first bisphenol carbonate units (1),
arylate-monoaryl ester units (7b), specifically ITR ester units
(7c), and siloxane units (9). For convenience, these polymers are
referred to herein as "PC-ITR-siloxane" copolymers.
[0073] In an embodiment, the PC-ITR-siloxane copolymers comprise 1
to 40 mol %, or 1 to 20 mol % of first bisphenol carbonate units
(1), 50 to 95 mol % of ITR ester units (7c), and an amount of
polysiloxane units (9b), specifically (9b-1), even more
specifically (9b-1), (9b-2), or a combination thereof effective to
provide 0.1 to 10 wt % of siloxane units, each based on the total
copolymer. For example, the PC-ITR-siloxane copolymers can comprise
1 to 20 mol % of bisphenol-A carbonate units, 60 to 90 mole % of
ITR ester units, and an amount of polysiloxane units (9b-2),
(9b-3), or a combination thereof effective to provide 0.1 to 10 wt
% of siloxane units, each based on the total copolymer.
[0074] As stated above, the polycarbonate copolymers comprising
first bisphenol carbonate units (1), monoaryl-arylate ester units
(7b), such as ITR units (7c), and siloxane units (9) can further
optionally comprise small amounts of other carbonate units, for
example 1 to 20 mole %, of other carbonate units, based on the
total moles of units in the copolymers. In an embodiment, the other
carbonate unit is derived from monoaryl dihydroxy compound (6).
Other arylate ester units can optionally be present, for example 1
to 20 mole % of arylate ester-bisphenol units (7b), based on the
total moles of units in the copolymers. A combination of the other
carbonate units and other ester units can be present, wherein the
total amount of the combination is 1 to 20 mole %. For example, the
ITR-PC-siloxane copolymers can further optionally comprise 1 to 20
mole % of resorcinol carbonate units, 1 to 20 mole % of bisphenol-A
arylate ester units, each based on the total moles of units in the
copolymers. Thus, the ITR-PC-siloxane copolymer can comprise 1 to
40 mol % of bisphenol-A carbonate units, 60 to 98 mol % of
isophthalic acid-terephthalic acid-resorcinol ester units, and 1 to
20 mol % of resorcinol carbonate units, isophthalic
acid-terephthalic acid-bisphenol-A ester units, or a combination
thereof. As above, these polycarbonate copolymers can comprise
siloxane units, specifically polysiloxane units (9b-2), (9b-3), or
a combination thereof in an amount effective to provide 0.1 to 25
wt %, 0.2 to 10 wt %, 0.2 to 6 wt % 0.2 to 5 wt %, or 0.25 to 2 wt
% of siloxane units, based on the total weight of the polycarbonate
copolymer, with the proviso that the siloxane units are covalently
bound to the polymer backbone of the polycarbonate copolymer.
[0075] Methods for the manufacture of the ITR-PC-siloxane
copolymers are known. The ITR-PC-siloxane copolymers can have an
intrinsic viscosity, as determined in chloroform at 25.degree. C.,
of 0.3 to 1.5 deciliters per gram (dl/g), specifically 0.45 to 1.0
dl/g. The PC-siloxane copolymers can have a weight average
molecular weight (M.sub.W) of 10,000 to 100,000 g/mol, as measured
by gel permeation chromatography (GPC) using a cross linked
styrene-divinyl benzene column, at a sample concentration of 1
milligram per milliliter, and as calibrated with polycarbonate
standards.
[0076] The low smoke density thermoplastic compositions comprise
the above-described polycarbonate copolymers, alone or in
combination, and 5 to 30 wt % of a polyetherimide, based on the
total weight of the thermoplastic composition. The polyetherimide
is of formula (10)
##STR00033##
wherein R is a substituted or unsubstituted divalent organic group
having 2 to 20 carbon atoms, for example a substituted or
unsubstituted aromatic hydrocarbon group having 6 to 20 carbon
atoms or a halogenated derivative thereof, a substituted or
unsubstituted, straight or branched chain alkylene group having 2
to 20 carbon atoms, a substituted or unsubstituted cycloalkylene
groups having 3 to 20 carbon atoms, or a divalent group of formula
(11)
##STR00034##
wherein Q is --O--, --S--, --C(O)--, --SO.sub.2--, --SO--, or
--C.sub.yH.sub.2y-- wherein y is an integer from 1 to 5 or a
halogenated derivative thereof.
[0077] The group Z in formula (10) is an aromatic C.sub.6-24
monocyclic or polycyclic group optionally substituted with 1 to 6
C.sub.1-8 alkyl groups, 1 to 8 halogen atoms, or a combination
thereof, wherein the divalent bonds of the --O--Z--O-- group are in
the 3,3', 3,4', 4,3', or the 4,4' positions.
[0078] In an embodiment, R in formula (10) is a divalent radical of
one of the following formulas
##STR00035##
wherein Q is --O--, --S--, --C(O)--, --SO.sub.2--, --SO--, or
--C.sub.yH.sub.2y-- wherein y is an integer from 1 to 5 or and a
halogenated derivative thereof; and Z is a divalent group of
formula (12)
##STR00036##
wherein Q.sup.1 is --O--, --S--, --C(O)--, --SO.sub.2--, --SO--, or
--C.sub.yH.sub.2y-- wherein y is an integer from 1 to 5. In an
embodiment no halogen substituents are present in the
polyetherimide.
[0079] Polyetherimides can be obtained by polymerization of an
aromatic bisanhydride of formula (13)
##STR00037##
wherein Z is as described in formula (10), with a diamine of the
formula H.sub.2N--R--NH.sub.2 wherein R is as described in formula
(10). Examples of specific aromatic bisanhydrides and organic
diamines are disclosed, for example, in U.S. Pat. Nos. 3,972,902
and 4,455,410 incorporated herein by reference in their entirety.
Illustrative examples of aromatic bisanhydrides (38) include
3,3-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride;
4,4'-bis(3,4-dicarboxyphenoxy)diphenyl ether dianhydride;
4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride;
4,4'-bis(3,4-dicarboxyphenoxy)benzophenone dianhydride;
4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfone dianhydride;
2,2-bis[4-(2,3-dicarboxyphenoxy)phenyl]propane dianhydride;
4,4'-bis(2,3-dicarboxyphenoxy)diphenyl ether dianhydride;
4,4'-bis(2,3-dicarboxyphenoxy)diphenyl sulfide dianhydride;
4,4'-bis(2,3-dicarboxyphenoxy)benzophenone dianhydride;
4,4'-bis(2,3-dicarboxyphenoxy)diphenyl sulfone dianhydride;
4-(2,3-dicarboxyphenoxy)-4'-(3,4-dicarboxyphenoxy)diphenyl-2,2-propane
dianhydride;
4-(2,3-dicarboxyphenoxy)-4'-(3,4-dicarboxyphenoxy)diphenyl ether
dianhydride;
4-(2,3-dicarboxyphenoxy)-4'-(3,4-dicarboxyphenoxy)diphenyl sulfide
dianhydride;
4-(2,3-dicarboxyphenoxy)-4'-(3,4-dicarboxyphenoxy)benzophenone
dianhydride and
4-(2,3-dicarboxyphenoxy)-4'-(3,4-dicarboxyphenoxy)diphenyl sulfone
dianhydride, as well as various mixtures comprising at least one of
the foregoing.
[0080] Illustrative examples of diamines H.sub.2N--R--NH.sub.2
include ethylenediamine, propylenediamine, trimethylenediamine,
diethylenetriamine, triethylenetetramine, hexamethylenediamine,
heptamethylenediamine, octamethylenediamine, nonamethylenediamine,
decamethylenediamine, 1,12-dodecanediamine, 1,18-octadecanediamine,
3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine,
4-methylnonamethylenediamine, 5-methylnonamethylenediamine,
2,5-dimethylhexamethylenediamine,
2,5-dimethylheptamethylenediamine, 2, 2-dimethylpropylenediamine,
N-methyl-bis (3-aminopropyl) amine, 3-methoxyhexamethylenediamine,
1,2-bis(3-aminopropoxy) ethane, bis(3-aminopropyl) sulfide,
1,4-cyclohexanediamine, bis-(4-aminocyclohexyl) methane,
m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene,
2,6-diaminotoluene, m-xylylenediamine, p-xylylenediamine,
2-methyl-4,6-diethyl-1,3-phenylene-diamine,
5-methyl-4,6-diethyl-1,3-phenylene-diamine, benzidine,
3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine,
1,5-diaminonaphthalene, bis(4-aminophenyl) methane,
bis(2-chloro-4-amino-3, 5-diethylphenyl) methane,
bis(4-aminophenyl) propane, 2,4-bis(amino-t-butyl) toluene,
bis(p-amino-t-butylphenyl) ether, bis(p-methyl-o-aminophenyl)
benzene, bis(p-methyl-o-aminopentyl) benzene, 1,
3-diamino-4-isopropylbenzene, bis(4-aminophenyl) sulfide, bis
(4-aminophenyl) sulfone, bis(4-aminophenyl) ether and
1,3-bis(3-aminopropyl) tetramethyldisiloxane. Combinations
comprising at least one of the foregoing aromatic bisanhydrides can
be used. Aromatic diamines are often used, especially m- and
p-phenylenediamine, sulfonyl dianiline, and combinations
thereof.
[0081] The thermoplastic compositions can include various other
polymers to adjust the properties of the thermoplastic
compositions, with the proviso that the other polymers are selected
so as to not adversely affect the desired properties of the
thermoplastic composition significantly, in particular low smoke
density and low heat release. For example, combination of a
polycarbonate copolymer as described above and a homopolycarbonate
such as a bisphenol-A homopolycarbonate can still provide
thermoplastic compositions having the required low smoke density.
Other polymers include an impact modifier such as natural rubber,
fluoroelastomers, ethylene-propylene rubber (EPR), ethylene-butene
rubber, ethylene-propylene-diene monomer rubber (EPDM), acrylate
rubbers, hydrogenated nitrile rubber (HNBR) silicone elastomers,
and elastomer-modified graft copolymers such as
styrene-butadiene-styrene (SBS), styrene-butadiene rubber (SBR),
styrene-ethylene-butadiene-styrene (SEBS),
acrylonitrile-butadiene-styrene (ABS),
acrylonitrile-ethylene-propylene-diene-styrene (AES),
styrene-isoprene-styrene (SIS), methyl
methacrylate-butadiene-styrene (MBS), high rubber graft (HRG), and
the like can be present. In general such other polymers provide
less than 50 wt %, less than 40 wt %, less than 30 wt %, less than
20 wt %, or less than 10 wt % of the total composition. In an
embodiment, no other polymers are present. In a specific
embodiment, no polymers containing halogen are present in the
thermoplastic compositions.
[0082] The thermoplastic compositions can include various additives
ordinarily incorporated into flame retardant compositions having
low smoke density and low heat release, with the proviso that the
additive(s) are selected so as to not adversely affect the desired
properties of the thermoplastic composition significantly, in
particular low smoke density and low heat release. Such additives
can be mixed at a suitable time during the mixing of the components
for forming the composition. Exemplary additives include fillers,
reinforcing agents, antioxidants, heat stabilizers, light
stabilizers, ultraviolet (UV) light stabilizers, plasticizers,
lubricants, mold release agents, antistatic agents, colorants such
as such as titanium dioxide, carbon black, and organic dyes,
surface effect additives, radiation stabilizers, additional flame
retardants, and anti-drip agents. A combination of additives can be
used. In general, the additives are used in the amounts generally
known to be effective. The total amount of additives (other than
any filler or reinforcing agents) is generally 0.01 to 25 parts per
parts per hundred parts by weight of the polymers (PHR).
[0083] The use of pigments such as titanium dioxide produces white
compositions, which are commercially desirable. Pigments such as
titanium dioxide (or other mineral fillers) can be present in the
thermoplastic compositions in amounts of 0 to 12 PHR, 0.1 to 9 PHR,
0.5 to 5 PHR, or 0.5 to 3 PHR.
[0084] Exemplary antioxidant additives include organophosphites
such as tris(nonyl phenyl)phosphite,
tris(2,4-di-t-butylphenyl)phosphite,
bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, distearyl
pentaerythritol diphosphite; alkylated monophenols or polyphenols;
alkylated reaction products of polyphenols with dienes, such as
tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]
methane; butylated reaction products of para-cresol or
dicyclopentadiene; alkylated hydroquinones; hydroxylated
thiodiphenyl ethers; alkylidene-bisphenols; benzyl compounds;
esters of beta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid
with monohydric or polyhydric alcohols; esters of
beta-(5-tert-butyl-4-hydroxy-3-methylphenyl)-propionic acid with
monohydric or polyhydric alcohols; esters of thioalkyl or thioaryl
compounds such as distearylthiopropionate, dilaurylthiopropionate,
ditridecylthiodipropionate,
octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,
pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate;
amides of beta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid,
or combinations comprising at least one of the foregoing
antioxidants. Antioxidants are used in amounts of 0.01 to 0.1
PHR.
[0085] Exemplary heat stabilizer additives include organophosphites
such as triphenyl phosphite, tris-(2,6-dimethylphenyl)phosphite,
and tris-(mixed mono- and di-nonylphenyl)phosphite; phosphonates
such as dimethylbenzene phosphonate, phosphates such as trimethyl
phosphate; or combinations comprising at least one of the foregoing
heat stabilizers. Heat stabilizers are used in amounts of 0.01 to
0.1 PHR.
[0086] Light stabilizers and/or ultraviolet light (UV) absorbing
additives can also be used. Exemplary light stabilizer additives
include benzotriazoles such as
2-(2-hydroxy-5-methylphenyl)benzotriazole,
2-(2-hydroxy-5-tert-octylphenyl)-benzotriazole and
2-hydroxy-4-n-octoxy benzophenone, or combinations comprising at
least one of the foregoing light stabilizers. Light stabilizers are
used in amounts of 0.01 to 5 PHR.
[0087] Exemplary UV absorbing additives include
hydroxybenzophenones; hydroxybenzotriazoles; hydroxybenzotriazines;
cyanoacrylates; oxanilides; benzoxazinones;
2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol
(CYASORB.RTM. 5411); 2-hydroxy-4-n-octyloxybenzophenone
(CYASORB.RTM. 531);
2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)-phe-
nol (CYASORB.RTM. 1164);
2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one) (CYASORB.RTM.
UV-3638);
1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,
3-diphenylacryloyl)oxy]methyl]propane (UVINUL.RTM. 3030);
2,2'-(1,4-phenylene) bis(4H-3,1-benzoxazin-4-one);
1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenyl-
acryloyl)oxy]methyl]propane; nano-size inorganic materials such as
titanium oxide, cerium oxide, and zinc oxide, all with particle
size less than or equal to 100 nanometers; or combinations
comprising at least one of the foregoing UV absorbers. UV absorbers
are used in amounts of 0.01 to 5 PHR.
[0088] Plasticizers, lubricants, and/or mold release agents can
also be used. There is considerable overlap among these types of
materials, which include phthalic acid esters such as
dioctyl-4,5-epoxy-hexahydrophthalate;
tris-(octoxycarbonylethyl)isocyanurate; tristearin;
poly-alpha-olefins; epoxidized soybean oil; silicones, including
silicone oils; esters, for example, fatty acid esters such as alkyl
stearyl esters, e.g., methyl stearate, stearyl stearate,
pentaerythritol tetrastearate, and the like; combinations of methyl
stearate and hydrophilic and hydrophobic nonionic surfactants
comprising polyethylene glycol polymers, polypropylene glycol
polymers, poly(ethylene glycol-co-propylene glycol) copolymers, or
a combination comprising at least one of the foregoing glycol
polymers, e.g., methyl stearate and polyethylene-polypropylene
glycol copolymer in a solvent; waxes such as beeswax, montan wax,
and paraffin wax. Such materials are used in amounts of 0.1 to 1
PHR.
[0089] Flame retardant salts are not needed to obtain the desired
low smoke and low heat release properties. Examples of flame
retardant salts include of C.sub.1-16 alkyl sulfonate salts such as
potassium perfluorobutane sulfonate (Rimar salt), potassium
perfluorooctane sulfonate, tetraethylammonium perfluorohexane
sulfonate, and potassium diphenylsulfone sulfonate (KSS); salts
such as Na.sub.2CO.sub.3, K.sub.2CO.sub.3, MgCO.sub.3, CaCO.sub.3,
and BaCO.sub.3, phosphate salts, or fluoro-anion complexes such as
Li.sub.3AlF.sub.6, BaSiF.sub.6, KBF.sub.4, K.sub.3AlF.sub.6,
KAlF.sub.4, K.sub.2SiF.sub.6, and/or Na.sub.3AlF.sub.6. In an
embodiment, no flame retardant salts are present. When present,
flame retardant salts are present in amounts of 0.01 to 10 PHR,
more specifically 0.02 to 1 PHR.
[0090] Organic flame retardants can be present, for example organic
compounds that include phosphorus, nitrogen, bromine, and/or
chlorine. However, halogenated flame retardants are generally
avoided, such that the thermoplastic composition can be essentially
free of chlorine and bromine. "Essentially free of chlorine and
bromine" as used herein means having a bromine and/or chlorine
content of less than or equal to 100 parts per million by weight
(ppm), less than or equal to 75 ppm, or less than or equal to 50
ppm, based on the total parts by weight of the composition,
excluding any filler.
[0091] In certain embodiments the thermoplastic compositions can
further comprise an organophosphorus flame retardant in an amount
effective to provide 0.1 to 1.0 wt % phosphorus, based on the
weight of the composition. For example, the organophosphorus
compound, specifically BPADP or RDP can be present in an amount of
2 to 10 wt %, which is effective to provide 0.1 to 1.0 wt %
phosphorus based on the total weight of the composition.
Organophosphorus compounds include aromatic organophosphorus
compounds having at least one organic aromatic group and at least
one phosphorus-containing group, as well as organic compounds
having at least one phosphorus-nitrogen bond.
[0092] In the aromatic organophosphorus compounds that have at
least one organic aromatic group, the aromatic group can be a
substituted or unsubstituted C.sub.3-30 group containing one or
more of a monocyclic or polycyclic aromatic moiety (which can
optionally contain with up to three heteroatoms (N, O, P, S, or
Si)) and optionally further containing one or more nonaromatic
moieties, for example alkyl, alkenyl, alkynyl, or cycloalkyl. The
aromatic moiety of the aromatic group can be directly bonded to the
phosphorus-containing group, or bonded via another moiety, for
example an alkylene group. The aromatic moiety of the aromatic
group can be directly bonded to the phosphorus-containing group, or
bonded via another moiety, for example an alkylene group. In an
embodiment the aromatic group is the same as an aromatic group of
the polycarbonate backbone, such as a bisphenol group (e.g.,
bisphenol-A), a monoarylene group (e.g., a 1,3-phenylene or a
1,4-phenylene), or a combination comprising at least one of the
foregoing.
[0093] The phosphorus-containing group can be a phosphate
(P(.dbd.O)(OR).sub.3), phosphite (P(OR).sub.3), phosphonate
(RP(.dbd.O)(OR).sub.2), phosphinate (R.sub.2P(.dbd.O)(OR)),
phosphine oxide (R.sub.3P(.dbd.O)), or phosphine (R.sub.3P),
wherein each R in the foregoing phosphorus-containing groups can be
the same or different, provided that at least one R is an aromatic
group. A combination of different phosphorus-containing groups can
be used. The aromatic group can be directly or indirectly bonded to
the phosphorus, or to an oxygen of the phosphorus-containing group
(i.e., an ester).
[0094] In an embodiment the aromatic organophosphorus compound is a
monomeric phosphate. Representative monomeric aromatic phosphates
are of the formula (GO).sub.3P.dbd.O, wherein each G is
independently an alkyl, cycloalkyl, aryl, alkylarylene, or
arylalkylene group having up to 30 carbon atoms, provided that at
least one G is an aromatic group. Two of the G groups can be joined
together to provide a cyclic group. In some embodiments G
corresponds to a monomer used to form the polycarbonate, e.g.,
resorcinol. Exemplary phosphates include phenyl bis(dodecyl)
phosphate, phenyl bis(neopentyl) phosphate, phenyl
bis(3,5,5'-trimethylhexyl) phosphate, ethyl diphenyl phosphate,
2-ethylhexyl di(p-tolyl) phosphate, bis(2-ethylhexyl) p-tolyl
phosphate, tritolyl phosphate, bis(2-ethylhexyl) phenyl phosphate,
tri(nonylphenyl) phosphate, bis(dodecyl) p-tolyl phosphate, dibutyl
phenyl phosphate, 2-chloroethyl diphenyl phosphate, p-tolyl
bis(2,5,5'-trimethylhexyl) phosphate, 2-ethylhexyl diphenyl
phosphate, and the like. A specific aromatic phosphate is one in
which each G is aromatic, for example, triphenyl phosphate,
tricresyl phosphate, isopropylated triphenyl phosphate, and the
like.
[0095] Di- or polyfunctional aromatic phosphorus-containing
compounds are also useful, for example, compounds of formula
(14)
##STR00038##
wherein each G.sup.2 is independently a hydrocarbon or
hydrocarbonoxy having 1 to 30 carbon atoms. In some embodiments G
corresponds to a monomer used to form the polycarbonate, e.g.,
resorcinol.
[0096] Specific aromatic organophosphorus compounds have two or
more phosphorus-containing groups, and are inclusive of acid esters
of formula (15)
##STR00039##
wherein R.sup.16, R.sup.17, R.sup.18, and R.sup.19 are each
independently C.sub.1-8 alkyl, C.sub.5-6 cycloalkyl, C.sub.6-20
aryl, or C.sub.7-12 arylalkylene, each optionally substituted by
C.sub.1-12 alkyl, specifically by C.sub.1-4 alkyl and X is a mono-
or poly-nuclear aromatic C.sub.6-30 moiety or a linear or branched
C.sub.2-30 aliphatic radical, which can be OH-substituted and can
contain up to 8 ether bonds, provided that at least one of
R.sup.16, R.sup.17, R.sup.18, R.sup.19, and X is an aromatic group.
In some embodiments R.sup.16, R.sup.17, R.sup.18, and R.sup.19 are
each independently C.sub.1-4 alkyl, naphthyl,
phenyl(C.sub.1-4)alkylene, or aryl groups optionally substituted by
C.sub.1-4 alkyl. Specific aryl moieties are cresyl, phenyl,
xylenyl, propylphenyl, or butylphenyl. In some embodiments X in
formula (15) is a mono- or poly-nuclear aromatic C.sub.6-30 moiety
derived from a diphenol. Further in formula (15), n is each
independently 0 or 1; in some embodiments n is equal to 1. Also in
formula (15), q is from 0.5 to 30, from 0.8 to 15, from 1 to 5, or
from 1 to 2. Specifically, X can be represented by the following
divalent groups (16), or a combination comprising one or more of
these divalent groups.
##STR00040##
[0097] In these embodiments, each of R.sup.16, R.sup.17, R.sup.18,
and R.sup.19 can be aromatic, i.e., phenyl, n is 1, and p is 1-5,
specifically 1-2. In some embodiments at least one of R.sup.16,
R.sup.17, R.sup.18, R.sup.19, and X corresponds to a monomer used
to form the polycarbonate, e.g., bisphenol-A or resorcinol. In
another embodiment, X is derived especially from resorcinol,
hydroquinone, bisphenol-A, or diphenylphenol, and R.sup.16,
R.sup.17, R.sup.18, R.sup.19, is aromatic, specifically phenyl. A
specific aromatic organophosphorus compound of this type is
resorcinol bis(diphenyl phosphate), also known as RDP. Another
specific class of aromatic organophosphorus compounds having two or
more phosphorus-containing groups are compounds of formula (17)
##STR00041##
wherein R.sup.16, R.sup.17, R.sup.18, R.sup.19, n, and q are as
defined for formula (19) and wherein Z is C.sub.1-7 alkylidene,
C.sub.1-7 alkylene, C.sub.5-12 cycloalkylidene, --O--, --S--,
--SO.sub.2--, or --CO--, specifically isopropylidene. A specific
aromatic organophosphorus compound of this type is bisphenol-A
bis(diphenyl phosphate), also known as BPADP, wherein R.sup.16,
R.sup.17, R.sup.18, and R.sup.19 are each phenyl, each n is 1, and
q is from 1 to 5, from 1 to 2, or 1.
[0098] Organophosphorus compounds containing at least one
phosphorus-nitrogen bond includes phosphazenes, phosphorus ester
amides, phosphoric acid amides, phosphonic acid amides, phosphinic
acid amides, and tris(aziridinyl) phosphine oxide. Phosphazenes
(18) and cyclic phosphazenes (19)
##STR00042##
in particular can used, wherein w1 is 3 to 10,000 and w2 is 3 to
25, specifically 3 to 7, and each R.sup.w is independently a
C.sub.1-12 alkyl, alkenyl, alkoxy, aryl, aryloxy, or
polyoxyalkylene group. In the foregoing groups at least one
hydrogen atom of these groups can be substituted with a group
having an N, S, O, or F atom, or an amino group. For example, each
R.sup.w can be a substituted or unsubstituted phenoxy, an amino, or
a polyoxyalkylene group. Any given R.sup.w can further be a
crosslink to another phosphazene group. Exemplary crosslinks
include bisphenol groups, for example bisphenol A groups. Examples
include phenoxy cyclotriphosphazene, octaphenoxy
cyclotetraphosphazene decaphenoxy cyclopentaphosphazene, and the
like. A combination of different phosphazenes can be used. A number
of phosphazenes and their synthesis are described in H. R. Allcook,
"Phosphorus-Nitrogen Compounds" Academic Press (1972), and J. E.
Mark et al., "Inorganic Polymers" Prentice-Hall International, Inc.
(1992).
[0099] Accordingly, depending on the particular organophosphorus
compound used, the thermoplastic compositions can comprise from 0.3
to 8.5 wt %, or 0.5 to 8.0 wt %, or 3.5 to 7.5 wt % of the
organophosphorus flame retardant, each based on the total weight of
the composition. Specifically, the organophosphorus compounds can
be bisphenol A bis(diphenyl phosphate), triphenyl phosphate,
resorcinol bis(diphenyl phosphate), tricresyl phosphate, or a
combination comprising at least one of the foregoing.
[0100] Anti-drip agents in most embodiments are not used in the
thermoplastic compositions. Anti-drip agents include a
fibril-forming or non-fibril forming fluoropolymer such as
polytetrafluoroethylene (PTFE). The anti-drip agent can be
encapsulated by a rigid copolymer, for example
styrene-acrylonitrile copolymer (SAN). PTFE encapsulated in SAN is
known as TSAN. Antidrip agents are substantially absent or
completely absent from the thermoplastic compositions in some
embodiments.
[0101] Methods for forming the thermoplastic compositions can vary.
In an embodiment, the polymers are combined (e.g., blended) with
any additives (e.g., a mold release agent) such as in a screw-type
extruder. The polymers any additives can be combined in any order,
and in form, for example, powder, granular, filamentous, as a
masterbatch, and the like. The thermoplastic compositions can be
foamed, extruded into a sheet, or optionally pelletized. Methods of
foaming a thermoplastic composition using frothing or physical or
chemical blowing agents are known and can be used. The pellets can
be used for molding into articles, foaming, or they can be used in
forming a sheet of the flame retardant thermoplastic composition.
In some embodiments, the composition can be extruded (or
co-extruded with a coating or other layer) in the form of a sheet
and/or can be processed through calendaring rolls to form the
desired sheet.
[0102] As discussed above, the thermoplastic compositions are
formulated to meet strict low smoke density requirements. The
relative amounts of polycarbonate copolymer and polyetherimide in
the thermoplastic compositions depends on the particular copolymer
and polyetherimide used, the targeted level of smoke density and
heat release, and other desired properties of the thermoplastic
composition, such as impact strength and flow. In an embodiment,
the polyetherimide is present in an amount from 5 to 30 wt %, based
on the total weight of the thermoplastic composition, and within
this range the specific amount is selected to be effective to
provide a smoke density (Ds-4) of less than 300, less than 250,
less than 200, less than 150, or less than 100 as determined in
accordance with ISO 5659-2 on a 3 mm thick plaque. These values can
be obtained in articles having a wide range of thicknesses, for
example from 0.1 to 10 mm, or 0.5 to 5 mm.
[0103] The thermoplastic compositions can further have a maximum
average rate of heat emission (MAHRE) of 90 kW/m.sup.2 or less, 75
kW/m.sup.2 or less, or 60 kW/m.sup.2 or less as measured according
to ISO 5660-1 on a 3 mm thick plaque.
[0104] Use of the PEI can lower smoke density (Ds-4) to the desired
levels. For example, PC-siloxane copolymers such as (bisphenol-A
carbonate)-co-(polydimethylsiloxane) and polycarbonate copolymers
such as (bisphenol-A carbonate)-co-PPPBP carbonate) have limited
inherent smoke properties, such that a combination with 5 to 30 wt
% of the polyetherimide has positive effect on the smoke density
(Ds-4) as determined according to ISO5659-2 on a 3 mm thick plaque,
such that these compositions are suitable for EN-45545 type
applications (for R1, R3 and R6 applications qualifying for HL2
compliance, a smoke density (Ds-4) at or below 300 is required),
provided that the other required properties (e.g. heat release)
meet the selection criteria as well. For ITR-PC-siloxane copolymers
such as (ITR ester)-co-(bisphenol-A
carbonate)-co-polydimethyl-siloxane)carbonate copolymers with good
inherent smoke and heat release properties, a combination with 5 to
30 wt % of the polyetherimide lowers the smoke density (Ds-4), as
determined according to ISO 5659-2 on a 3 mm thick plaque, even
further so that more stringent fire requirements can be met, more
specifically Hazard Level 3 requirements for R6 applications in the
EN45545 norm (for R1, R3 and R6 applications qualifying for HL3
compliance, a smoke density (Ds-4) at or below 150 or 300 is
required), provided that the other required properties (e.g. heat
release) meet the selection criteria as well.
[0105] Thus, in some embodiments the compositions can have a smoke
density (Ds-4) of 300 or less as determined according to ISO 5659-2
on a 3 mm thick plaque. In a specific embodiment, a thermoplastic
composition comprising a combination of ITR-PC with ITR-PC-siloxane
has a smoke density (Ds-4) of 150 or less as determined according
to ISO 5659-2 and maximum heat release rate (MAHRE) of 90
kW/m.sup.2 or less as determined according to ISO 5660-1, both on a
3 mm thick plaque. These values can be obtained in articles having
a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5
to 5 mm. These low smoke density and heat release values are
obtained using a combination of an ITR-PC and an ITR-PC-siloxane in
a weight ratio of 10:90 to 90:10, specifically 20:80 to 80:20. In
an embodiment the ITR-PC comprises ITR and bisphenol-A carbonate
units as described above, and the ITR-PC-siloxane comprises ITR
ester units, bisphenol-A carbonate units, and siloxane units
(9b-2), (9b-3), or a combination thereof as described above. The
compositions can further comprise an aromatic organophosphorus
compound, e.g., RDP, BPDA, or a combination comprising at least one
of the foregoing aromatic organophosphorus compounds.
[0106] The thermoplastic compositions can be formulated to have
lower densities, in particular a density of 1.35 g/cc or less, 1.34
g/cc or less, 1.33 g/cc or less, 1.32 g/cc or less, 1.31 g/cc or
less, 1.30 g/cc or less, or 1.29 g/cc or less. The same or similar
values can be obtained in components having a wide range of
thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.
[0107] The thermoplastic compositions can further have good melt
viscosities, which aid processing. The thermoplastic compositions
can have a melt volume flow rate (MVR, cubic centimeter per 10
minutes (cc/10 min), according to of 4 to about 30, greater than or
equal to 10, greater than or equal to 12, greater than or equal to
15, greater than or equal to 16, greater than or equal to 17,
greater than or equal to 18, greater than or equal to 19, or
greater than or equal to 20 cc/min, measured at 300.degree. C./1.2
Kg at 360 second dwell according to ISO 1133. The same or similar
values can be obtained in articles having a wide range of
thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.
[0108] The thermoplastic compositions can further have excellent
impact properties, in particular multiaxial impact (MAI) and
ductility. The compositions can have an MAI equal to or higher than
100 J, determined at 23.degree. C. at an impact speed of 4.4
m/second in accordance with ISO 6603 on discs with a thickness of
3.2 mm. The compositions can have a ductility in multiaxial impact
of 80% and higher, determined at 23.degree. C. at an impact speed
of 4.4 m/second in accordance with ISO 6603 on discs with a
thickness of 3.2 mm. These values can be obtained in articles
having a wide range of thicknesses, for example from 0.1 to 10 mm,
or 0.5 to 5 mm.
[0109] As noted above the present discovery allows the manufacture
of compositions have very low smoke densities (Ds-4), as determined
according to ISO5659-2 on a 3 mm thick plaque and heat release
(MAHRE) as determined according to ISO5660-1 on a 3 mm thick
plaque, while maintaining the advantageous properties of
polycarbonates. Thus, thermoplastic compositions having practical
impact properties within 20%, within 10%, within 5%, or within 1%
of the same compositions without the polyetherimides can be
manufactured. For example, the thermoplastic compositions can have
an MAI within 20%, within 10%, within 5%, or within 1% of the MAI
of the same composition, each determined at 23.degree. C. at an
impact speed of 4.4 m/second in accordance with ISO 6603 on discs
with a thickness of 3.2 mm. The white or almost-white color of the
polycarbonates can further be maintained.
[0110] Shaped, formed, or molded articles comprising the
thermoplastic compositions are also provided. The thermoplastic
compositions can be molded into useful shaped articles by a variety
of means such as injection molding, extrusion, rotational molding,
blow molding, and thermoforming to form articles. Thus the
thermoplastic compositions can be used to form a foamed article, a
molded article, a thermoformed article, an extruded film, an
extruded sheet, one or more layers of a multi-layer article (e.g. a
cap-layer), a substrate for a coated article, or a substrate for a
metallized article.
[0111] Illustrative articles include access panels, access doors,
air flow regulators air gaspers, air grilles, arm rests, baggage
storage doors, balcony components, cabinet walls, ceiling panels,
door pulls, door handles, duct housing, enclosures for electronic
devices, equipment housings, equipment panels, floor panels, food
carts, food trays, galley surfaces, grilles, handles, housings for
TVs and displays, light panels, magazine racks, telephone housings,
partitions, parts for trolley carts, seat backs, seat components,
railing components, seat housings, shelves, side walls, speaker
housings, storage compartments, storage housings, toilet seats,
tray tables, trays, trim panel, window moldings, window slides,
windows, and the like.
[0112] In an embodiment, the thermoplastic compositions are
formulated to provide articles that meet certain criteria set forth
in the new European Railway standard EN-45545 (2013). The European
Union has approved the introduction of a set of fire testing
standards for the railroad industry that prescribes certain
flammability, flame spread rate, heat release, smoke emission, and
smoke toxicity requirements for materials used in railway vehicles,
known as European Railway standard EN-45545 (2013). Based on the
vehicle material, end-use, and fire risks, 26 different
"Requirement" categories for materials have been established
(R1-R26).
[0113] Passenger seat shells (both back and base shell) fall under
the R6 application type. Lighting strips fall under the R3
application type. The R1 application type covers, amongst others,
interior vertical and horizontal surfaces, such as side walls,
front/end walls, doors, ceiling panels, as well as luggage racks,
linings and frames.
[0114] "Hazard Levels" (HL1 to HL3) have been designated,
reflecting the degree of probability of personal injury as the
result of a fire. The levels are based on dwell time and are
related to operation and design categories. HL1 is the lowest
hazard level and is typically applicable to vehicles that run under
relatively safe conditions (easy evacuation of the vehicle). HL3 is
the highest hazard level and represents most dangerous
operation/design categories (difficult and/or time-consuming
evacuation of the vehicle, e.g. in underground rail cars). For each
application type, different test requirements for the hazard levels
are defined. The testing methods, and smoke density (Ds-4) and
maximum heat release (MAHRE) values for the various hazard levels
in the European Railway standard EN-45545 (2013) are shown in Table
1B for R6 applications.
TABLE-US-00001 TABLE 1B European Railways Standard EN 45545 for R6
applications Hazard Smoke Density, DS-4 Heat release, MAHRE
(kW/m.sup.2) Level ISO 5659-2 ISO 5660-1 HL1 .ltoreq.600 -- HL2
.ltoreq.300 .ltoreq.90 HL3 .ltoreq.150 .ltoreq.60
[0115] Data in the Examples shows that the compositions herein can
meet the requirements for HL2, and some compositions can meet the
requirements for HL3.
[0116] Thus, while thermoplastic compositions can be used for the
manufacture of a wide variety of articles, including high occupancy
structures such as rail stations, airports and office buildings,
the thermoplastic compositions are especially useful for the
manufacture of transportation components.
[0117] As used herein, a "transportation component" is an article
or portion of an article used in rolling stock, an aircraft, a
roadway vehicle, or a marine vehicle. "Rolling stock" includes but
is not limited to a locomotive, coach, light rail vehicle,
underground rail vehicle, tram, trolley, magnetic levitation
vehicle, and a cable car. An "aircraft" includes but is not limited
to a jet, an airplane, an airship, a helicopter, a balloon, and a
spacecraft. A "roadway vehicle" includes but is not limited to an
automobile, bus, scooter and a motorcycle. A "marine vehicle"
includes but is not limited to a boat, a ship (including freight
and passenger ships), jet skis, and a submarine.
[0118] Exemplary transportation components for rolling stock (e.g.
trains), aircraft, and roadway and marine vehicles, particularly
rolling stock, includes interior components (e.g., structure and
coverings) such as ceiling paneling, flaps, boxes, hoods, louvers,
insulation material and the body shell in interiors, side walls,
front walls/end walls, partitions, room dividers, interior doors,
interior lining of the front-/end-wall doors and external doors,
luggage overhead luggage racks, vertical luggage rack, luggage
container, luggage compartments, windows, window frames, kitchen
interiors, surfaces or a component assembly comprising at least one
of the foregoing. In an embodiment any of the foregoing articles
are in compliance with European Rail Standard EN-45545, for example
meeting HL2 or HL3.
[0119] The thermoplastic compositions are particularly useful in
train and aircraft, for example a variety of aircraft compartment
interior applications, as well as interior applications for other
modes of transportation, such as bus, train, subway, marine, and
the like. In a specific embodiment the articles are interior
components for aircraft or trains, including access panels, access
doors, air flow regulators baggage storage doors, display panels,
display units, door handles, door pulls, enclosures for electronic
devices, food carts, food trays, grilles, handles, magazine racks,
seat components, partitions, refrigerator doors, seat backs, side
walls, tray tables, trim panels, and the like. The poly(siloxane)
copolymer compositions can be formed (e.g., molded) into sheets
that can be used for any of the above mentioned components. It is
generally noted that the overall size, shape, thickness, optical
properties, and the like of the polycarbonate sheet can vary
depending upon the desired application. In an embodiment any of the
foregoing articles are in compliance with European Rail Standard
EN-45545, for example meeting HL2 or HL3.
[0120] Certain of the above-described compositions are particularly
useful for the manufacture of a transportation component, in
particular an aircraft component or a rolling stock component
(e.g., a train component) having a smoke density (Ds-4) of less
than 300, less than 180, or less than 150 (measured in accordance
with ISO 5659-2 on a 3 mm thick plaque), and a MAHRE of less than
90 kW/m.sup.2, or less than 60 (measured using ISO 5660-1 on a 3 mm
thick plaque). Such materials can be in compliance with EN-45545
(2013), for example meeting HL2 or HL3. In an embodiment these
compositions comprise the PC-siloxane, or the PC-siloxane in
combination with another polycarbonate copolymer or
homopolycarbonate together with 5 to 30 wt % of PEI. An
organophosphorus compound can be present in the compositions. In
particular, PC-siloxanes containing bisphenol-A carbonate units and
polysiloxane units of formulas (9a), (9b), or a combination thereof
can be used, optionally in combination with a bisphenol-A
homopolycarbonate, and further optionally in combination with an
aromatic organophosphorus compound such as RDP or BPADP in an
amount effective to provide 0.1 to 1.0 wt % of phosphorus. The same
compositions without PEI either do not meet strict low smoke
density (Ds-4) standards, failing to meet Hazard Level 2
requirements for EN45545 compliance, requiring a Ds-4 equal to or
below 300. However, the thermoplastic compositions with the
polyetherimide have Ds-4 values lower than 300, as determined
according to ISO 5659-2 on 3 mm thick plaques, and as such can meet
the smoke density requirements for Hazard Level 2 applications
according to EN45545 (requiring Ds-4 values equal to or lower than
300) and simultaneously have very low heat release (MAHRE)
properties without compromising mechanical properties such as
impact resistance and processability. These values can be obtained
in articles having a wide range of thicknesses, for example from
0.1 to 10 mm, or 0.5 to 5 mm.
[0121] In another embodiment these compositions comprise an ITR-PC,
and ITR-PC-siloxane copolymer, or a combination of an ITR-PC and an
ITR-PC-siloxane copolymer together with 5 to 30 wt % of PEI. An
organophosphorus compound can be present in the compositions. The
ITR-PC can comprise ITR ester units and bisphenol-A carbonate
units, and the ITR-PC-siloxane copolymer can comprise ITR ester
units, bisphenol-A carbonate units, and polysiloxane units of
formulas (9a), (9b), or a combination thereof, and an
organophosphorus compound can be present, such as RDP or BPADP in
an amount effective to provide 0.1 to 1.0 wt % of phosphorus. The
same compositions without PEI only have smoke density (Ds-4) values
below 300, as determined according to ISO5659-2 on 3 mm thick
samples, which would make them suitable for Hazard Level 2
applications according to EN45545 (requiring Ds-4 values equal to
or lower than 300). However, the thermoplastic compositions with
the polyetherimide have Ds-4 values below 150, as determined
according to ISO5659-2 on 3 mm thick plaques and as such can meet
the smoke density requirements for the most stringent Hazard Level
3 for EN45545 applications (requiring Ds-4 values equal to or below
150) and simultaneously have very low heat-release properties
without compromising mechanical properties such as impact
resistance and processability.
[0122] The thermoplastic compositions having low smoke density and
low heat release rates are further illustrated by the following
non-limiting examples.
EXAMPLES
[0123] Materials for the following examples are listed in Table
2.
TABLE-US-00002 TABLE 2 Component Trade name, Description Source
ITR-PC Isophthalic acid-terephthalic acid-resorcinol)-bisphenol-A
SABIC INNOVATIVE poly(ester-co-carbonate), ester content 83 mol %,
interfacial PLASTICS polymerization, Mw = 19,000 to 23,000 g/mol
(determined via GPC using polycarbonate standards), PCP end-capped
ITR-PC-siloxane Isophthalic acid-terephthalic
acid-resorcinol)-bisphenol-A SABIC INNOVATIVE
poly(ester-co-carbonate) with poly(siloxane) blocks, ester PLASTICS
content 83 mol %, poly(siloxane) content 1 wt % (average chain
length about 10 units), interfacial polymerization, Mw = 22,500 to
26,500 g/mol (determined via GPC using polycarbonate standards),
PCP end-capped PEI polyetherimide made via reaction of bisphenol-A
dianhydride SABIC INNOVATIVE with equimolar amount of m-phenylene
diamine, Mw = 31,000 PLASTICS to 35,000 g/mol (determined via GPC
using polystyrene standards) PPPBP-BPA
N-phenylphenolphthaleinylbisphenol, 2,2-bis(4-hydro))- SABIC
INNOVATIVE bisphenol-A copolymer, 32 mol % PPPBP, Mw = 23,000 to
PLASTICS 27,000 g/mol (determined via GPC using polycarbonate
standards), manufactured by interfacial polymerization BPA-PC
Bisphenol-A polycarbonate, manufactured by interfacial SABIC
INNOVATIVE polymerization, Mw = 28,000 to 32,000 g/mol (determined
via PLASTICS GPC using polycarbonate standards) PPSU Radel 5100;
poly(phenylenesulfone) SOLVAY PC-siloxane PDMS
(polydimethylsiloxane)-bisphenol-A copolymer, 6 mol SABIC
INNOVATIVE wt % siloxane having an average block length of 40-50
PLASTICS units, Mw 23,000 g/mol (determined via GPC using
polycarbonate standards), manufactured by interfacial
polymerization PEPQ
Tetrakis(2,4-di-tert-butylphenyl)[1,1-biphenyl]- Clariant
4,4'diylbisphosphonite IRGAPHOS 168 Tris(di-t-butylphenyl)phosphite
BASF IRGANOX 1076 Octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)
propionate BASF TiO.sub.2 Coated titanium dioxide DuPont Titanium
Carbon black Amorphous Carbon Cabot
[0124] The tests performed are summarized in Table 3.
TABLE-US-00003 TABLE 3 Description Test Specimen Property Units ISO
Smoke density ISO 5659-2 plaque 75 .times. 75 .times. 3 mm DS-4
[--] ISO Heat release ISO 5660-1 plaque 100 .times. 100 .times. 3
mm MAHRE kW/m.sup.2 Melt volume flow rate ISO 1133 Pellets MVR
cc/10 min at 300.degree. C. Izod Notched Impact, ISO 180/1A
Multi-purpose ISO 3167 Type A, INI kJ/m.sup.2 23.degree. C., 5.5 J
4 mm thickness Multiaxial Impact, ISO 6603 Disc, 3.2 mm thickness,
100 mm MAI J 23.degree. C., 4.4 m/s diameter
[0125] Smoke density measurements were performed on 7.5.times.7.5
cm plaques with 3 mm thickness using a National Bureau of Standards
(NBS) Smoke Density Chamber from Fire Testing Technology Ltd (West
Sussex, United Kingdom). All measurements were performed according
to ISO5659-2, with an irradiance of 50 kW/m.sup.2 at the sample
position and a sample-to-cone distance of 5 cm in view of the
charring behavior of the samples (as prescribed by ISO5659-2). Ds-4
was determined as the measured smoke density after 240 seconds.
[0126] Heat release measurements were performed on 10.times.10 cm
plaques with 3 mm thickness using a Cone calorimeter. All
measurements were performed according to ISO 5660-1, with an
irradiation of 50 kW/m.sup.2 at the sample position and a
sample-to-cone distance of 6 cm in view of the charring behavior of
the samples (as prescribed by ISO5660-1).
[0127] The smoke density and heat release tests executed are
indicative tests. They were performed according to their respective
ISO standards, but were not executed by an officially certified
test institute.
Blending, Extrusion, and Molding Conditions
[0128] The compositions were made as follows. All solid additives
(e.g., stabilizers, colorants, solid flame retardants) were dry
blended off-line as concentrates using one of the primary polymer
powders as a carrier and starve-fed via gravimetric feeder(s) into
the feed throat of the extruder. The remaining polymer(s) were
starve-fed via gravimetric feeder(s) into the feed throat of the
extruder as well. The liquid flame retardants (e.g., BPADP) were
fed before the vacuum using a liquid injection system. It will be
recognized by one skilled in the art that the method is not limited
to these temperatures or processing equipment.
[0129] Extrusion of all materials was performed on a 25 mm
Werner-Pfleiderer ZAK twin-screw extruder (L/D ratio of 33/1 with a
vacuum port located near the die face. The extruder has 9 zones,
which were set at temperatures of 40.degree. C. (feed zone),
200.degree. C. (zone 1), 250.degree. C. (zone 2), 270.degree. C.
(zone 3) and 280-300.degree. C. (zone 4 to 8). Screw speed was 300
rpm and throughput was between 15 and 25 kg/hr.
[0130] The compositions were molded after drying at 100-110.degree.
C. for 6 hours on a 45-ton Engel molding machine with 22 mm screw
or 75-ton Engel molding machine with 30 mm screw operating at a
temperature 270-300.degree. C. with a mold temperature of
70-90.degree. C. It will be recognized by one skilled in the art
that the method is not limited to these temperatures or processing
equipment.
Examples 1-8
[0131] Examples 1-8 demonstrate the effect of the addition of
polyetherimide (PEI) to Isophthalic acid-terephthalic
acid-resorcinol)-bisphenol-A poly(ester-co-carbonate) (ITR-PC)
copolymers on smoke density (Ds-4) and heat release (MAHRE)
properties as well as mechanical properties. Formulations and
results are shown in Table 4.
TABLE-US-00004 TABLE 4 Component CEx1 Ex2 Ex3 Ex4 Ex5 CEx6 Ex7 CEx8
ITR-PC 99.94 89.94 79.94 74.94 69.94 59.94 39.94 -- PEPQ 0.06 0.06
0.06 0.06 0.06 0.06 0.06 -- PEI 10 20 25 30 40 60 100 Property INI,
23.degree. C., 5.5 J 16 13 11 10 9 8 6 5 MAI, 23.degree. C., 4.4
m/s 119 120 135 135 121 143 133 10 MAI, ductility % 100 80-100
80-100 80-100 80-100 80-100 20 0 MVR, 330.degree. C., 2.16 kg 64.3
48.5 35.2 34.2 31.9 24.4 15.6 -- Smoke density, 186 93 77 76 69 --
-- 72 DS-4 Heat release, 125 -- 98 -- 81 79 -- 45 MAHRE
As shown in Table 4 and illustrated graphically in FIG. 1, smoke
density (Ds-4) decreases upon addition of PEI, with values similar
to 100 wt % PEI obtained already at 20-30 wt % of PEI loading (Ds-4
of 77, 76 and 69 for 20, 25 and 30% respectively, compared to Ds-4
of 72 for 100 wt % PEI, all measured on 3 mm thick plaques). As
shown in FIG. 1, the decrease in smoke density (Ds-4) as a function
of fractional concentration of PEI is non-linear, following a
behavior indicating strong interaction between the PEI and the
ITR-PC copolymer. An interaction parameter k was calculated based
on the following equation.
Ds Blend = w ITR - PC Ds ITR - PC Pure + kw PEI Ds PEI pure w ITR -
PC + kw PEI ( Eq . 1 ) ##EQU00001##
where [0132] W.sub.ITR-PC and W.sub.PEI are the fractional
concentration of the ITR-PC and PEI copolymers respectively; [0133]
k is the interaction parameter; and [0134] Ds is the smoke
density.
[0135] The interaction parameter (k) is much larger (k=52.7), than
expected based upon simple rules of mixture (k=1, indicating no
interaction), which results in compositions with smoke densities
(Ds-4) comparable to 100 wt % PEI, as determined according to ISO
5659-2 on 3 mm thick plaques, with significant benefits in flow and
impact properties. The compositions containing up to 30% of
polyetherimide have similar multiaxial impact properties, both
impact energy (120-135 J) and ductility (80-100%), as determined
according to ISO 6603 on 3.2 mm thick discs, as the composition
without polyetherimide (CEx1, impact energy of 119 J and ductility
of 100%). In contrast, compositions containing high amounts of
polyetherimide (CEx7) or only polyetherimide (CEx8) have
significantly worse ductility levels (20% and 0% for CEx6 and CEx7
respectively) and/or impact energy (10J for CEx7) than the
composition containing only polycarbonate copolymer (CEx1).
[0136] The results demonstrate that ITR-PC-siloxane copolymers with
10-30% PEI based on the weight of the composition has a smoke
density (Ds-4) below 150 as determined according to ISO 5659-2 on 3
mm thick plaque, which qualifies for rail components of Hazard
Level 3 designation according to the European Railway Standard EN
45545 (for R6 applications qualifying for HL3 compliance, a smoke
density (Ds-4) at or below 150 is required), provided that the
other required properties (e.g. heat release) meet the selection
criteria as well, whereas formulations without PEI do not meet
these HL3 requirements for Ds-4 (e.g. CEx1 has a Ds-4 of 186 as
determined according to ISO5659-2 on 3 mm thick plaque, which would
only meet HL2, requiring Ds-4.ltoreq.300 for R6
applications).).
Examples 9-12
[0137] Examples 9-12 demonstrate the effect of the addition of
polyetherimide (PEI) to polycarbonate copolymer combinations with
high isophthalic acid-terephthalic acid-resorcinol contents, namely
ITR-PC-siloxane copolymers and ITR-PC copolymers on smoke density
(Ds-4). Formulations and results are shown in Table 5.
TABLE-US-00005 TABLE 5 Ex9 Ex10 CEx11 CEx12 Component
ITR-PC-siloxane 44.97 38.92 49.97 0 ITR-PC 44.97 38.92 49.97 0 PEPQ
0.06 0.06 0.06 0 TiO.sub.2 2.0 2.0 2.0 0 Carbon black 0.10 0.1 0.10
0 PEI 10 20 0 100 Property DS-4 111 76 158 72
[0138] As shown in Table 5 and illustrated in FIG. 7, smoke density
(Ds-4) decreases upon addition of PEI, with values similar to 100
wt % PEI already at 20 wt % of PEI loading (DS-4 of 76, compared to
DS-4 of 72 for 100 wt % PEI, all measured on a 3 mm thick
plaque).
[0139] Similar to ITR-PC copolymers alone, the interaction
parameter (k) was calculated for the ITR-PC/ITR-PC-siloxane
combination using the equation
Ds Blend = w ITR - PCD / ITR - PC - Si Ds 100 % ITR - PC / ITR - PC
- Si + kw PEI Ds PEI pure w ITR - PC / ITR - PC - Si + kw PEI ( Equ
.2 ) ##EQU00002##
[0140] The calculated interaction parameter (k=16.4) is much larger
than expected based upon simple rules of mixture (k=1), which
results in compositions with smoke densities comparable to 100 wt %
PEI, at PEI fractional concentrations of 20% (Ex. 10).
[0141] The results demonstrate that combinations of ITR-PC-siloxane
and ITR-PC copolymers having 10 wt % and 20 wt % PEI have a smoke
density (Ds-4) below 150 as determined according to ISO5659-2 on a
3 mm thick plaque, which qualifies these compositions for forming
rail components of Hazard Level 3 designation according to the
European Railway Standard EN 45545 (for R6 applications qualifying
for HL3 compliance, a smoke density (Ds-4) at or below 150 is
required), provided that the other required properties (e.g. heat
release) meet the selection criteria as well, whereas identical
formulations without PEI do not meet these HL3 requirements for
Ds-4 (e.g. CEx11 has a Ds-4 of 158 as determined according to
ISO5659-2 on a 3 mm thick plaque, which only meets HL2 requiring
Ds-4.ltoreq.300 for R6 applications).).
Examples 13-17
[0142] To determine whether the observed non-linear effect on smoke
density (Ds-4) occurs, polymers with inherently low smoke density
values different than PEI, were used as additives. Examples 13-17
demonstrate the effect of the addition of PPSU to ITR-PC copolymer.
Formulations and results are shown in Table 6.
TABLE-US-00006 TABLE 6 CEx13 CEx14 CEx15 CEx16 CEx17 Component
ITR-PC 100 90 80 70 0 PPSU 0 10 20 30 100 Property Smoke density,
DS-4 186 194 194 133 67
[0143] As shown in Table 6 and FIG. 2, there is no decrease in
smoke density (Ds-4) as a function of PPSU loading beyond the
expected by rules of mixture for these compositions (k=1), unlike
the results observed for the addition of PEI to ITR-PC copolymers
and combinations of ITR-PC with ITR-PC-siloxane copolymers. Rather,
the effect is linear. The results demonstrate that the observed
interactive, non-linear effect of PEI addition to high ITR content
polycarbonate copolymer on the smoke density is unexpected and does
not translate automatically to other polymers with inherently very
low smoke density values similar to PEI.
Examples 18-22
[0144] To determine whether the non-linear effect on smoke density
(Ds-4) upon PEI addition occurs with other polycarbonate copolymers
as well, Examples 18-22 demonstrate the effect of the addition of
PEI to PPPBP-PC copolymers. Table 7 shows the formulations and
results.
TABLE-US-00007 TABLE 7 CEx18 Ex19 Ex20 Ex21 CEx22 Component
PPPBP-BPA 100 90 80 70 0 PEI 0 10 20 30 100 Property Smoke density,
DS-4 626 493 240 245 72
[0145] As shown in Table 7 and FIG. 3, the decrease in smoke
density (Ds-4) as a function of PEI loading is non-linear and much
larger than expected based upon simple rules of mixture (k=5.2
calculated according to the Equation in FIG. 3).
[0146] The addition of PEI to PPPBP-BPA copolymers reduces the
smoke density to such an extent that formulations containing PEI
have smoke density (Ds-4) values below 300 (Ds-4 about 250 as
determined according to ISO5659-2 on a 3 mm thick plaque on 3 mm
thick plaque), which would make them suitable for EN-45545 type
applications (for R1, R3 and R6 applications qualifying for HL2
compliance, a smoke density (Ds-4) at or below 300 is required,
while for HL3 compliance, a smoke density (Ds-4) at or below 150 is
required), provided that the other required properties (e.g. heat
release) meet the selection criteria as well, whereas formulations
without PEI do not meet these HL2 requirements for Ds-4 (Ds-4 of
626 for CEx18 as determined according to ISO5659-2 on a 3 mm thick
plaque, which would fail to meet even HL-1, requiring
Ds-4.ltoreq.600 for R6 applications).
Examples 23-26
[0147] To determine whether the non-linear effect on smoke density
(Ds-4) holds for other polycarbonates containing siloxanes, PEI was
added in increasing concentrations to a PC-siloxane and smoke
density was measured. Results and formulations are shown in Table
8.
TABLE-US-00008 TABLE 8 CEx23 Ex24 Ex25 CEx26 Component PC-siloxane
99.88 84.88 69.88 0 IRGANOX 1076 0.04 0.04 0.04 0 IRGAPHOS 168 0.08
0.08 0.08 0 PEI 0 15 30 100 Property Smoke density, DS-4 935 198
166 72
[0148] As shown in Table 9 and FIG. 4, the decrease in smoke
density (Ds-4) as a function of PEI concentration is non-linear and
much larger than expected based upon simple rules of mixture
(k=16.2 calculated according to the Equation in FIG. 4).
[0149] The addition of PEI to PC-siloxane copolymers reduces the
smoke density (Ds-4) to such an extent that formulations containing
PEI have smoke density (Ds-4) values (Ds-4 of 198 and 166
respectively, as determined according to ISO5659-2 on 3 mm thick
plaque at 15% and 30% PEI, Ex24 and Ex25) below 300, which would
make them suitable for EN-45545 type applications (for R6
applications qualifying for HL2 compliance, a smoke density (Ds-4)
at or below 300 is required), provided that the other required
properties (e.g. heat release) meet the requirements as well,
whereas formulations without PEI do not meet these requirements
(see e.g. CEx23, having Ds-4 of 935 as determined according to
ISO5659-2 on 3 mm thick plaque, which would fail to meet even HL-1,
requiring Ds-4.ltoreq.600 for R6 applications).
Examples 27-30
[0150] To determine whether the non-linear effect on smoke density
(Ds-4) is true for polycarbonate homopolymers, PEI at different
concentrations was added to a polycarbonate homopolymer (PC).
Results and formulations are shown in Table 9.
TABLE-US-00009 TABLE 9 CEx27 Ex28 Ex29 CEx30 Component PC 99.88
84.88 69.88 0 IRGANOX 1076 0.04 0.04 0.04 0 IRGAPHOS 168 0.08 0.08
0.08 0 PEI 0 15 30 100 Property Smoke density, DS-4 1320 703 493
72
[0151] As shown in Table 9 and graphically illustrated in FIG. 5,
the decrease in smoke density (Ds-4) as a function of PEI
concentration is non-linear and larger than expected based upon
simple rules of mixture (k=4.4 calculated according to the Equation
in FIG. 5).
[0152] The addition of PEI to polycarbonate homopolymer (PC)
reduces the smoke density (Ds-4) (Ds-4 of 493 as determined
according to ISO5659-2 on a 3 mm thick plaque at 30% PEI), but not
to below 300. The addition of PEI to PC homopolymer reduces the
smoke density (Ds-4) to such a degree that formulations containing
PEI have smoke density (Ds-4) values (Ds-4 of 493 at 30% PEI as
determined according to ISO5659-2 on a 3 mm thick plaque, Ex29)
below 600, making them suitable for EN-45545 type applications (for
R6 applications qualifying for HL1 compliance, a Ds-4 smoke density
at or below 600 is required), provided that the other required
properties (e.g. heat release) meet the requirements as well,
whereas formulations without PEI do not meet these requirements
(see CEx27, having Ds-4 of 1320 as determined according to
ISO5659-2 on a 3 mm thick plaque, which would fail to meet even
HL-1, requiring Ds-4.ltoreq.600 for R6 applications).
Examples 31-35
[0153] To determine whether the interaction-indicating, non-linear
effect on smoke density (Ds-4) holds for combinations of
polycarbonate homopolymer and polycarbonate copolymer, PEI at
different concentrations was added to a combination of
polycarbonate homopolymer (BPA-PC) and PC-siloxane. Results and
formulations are shown in Table 10.
TABLE-US-00010 TABLE 10 CEx31 Ex32 Ex33 Ex34 CEx35 Component BPA-PC
49.94 44.94 39.94 34.94 0 PC-Si 49.94 44.94 39.94 34.94 0 IRGANOX
1076 0.04 0.04 0.04 0.04 0 IRGAPHOS 168 0.08 0.08 0.08 0.08 0 PEI 0
10 20 30 100 Property Smoke density, DS-4 720 415 246 147 72
[0154] As shown in Table 10 and illustrated graphically in FIG. 6,
the decrease in smoke density (Ds-4) as a function of PEI
concentration is non-linear and much larger than expected based
upon simple rules of mixture (k=10.1 calculated according to the
Equation in FIG. 6).
[0155] The addition of PEI to combinations of a polycarbonate
homopolymer and a PC-siloxane can reduce the smoke density (Ds-4)
to such an extent that formulations containing PEI have smoke
density (Ds-4) values below 300 (Ds-4 of 246 (Ex33) and 147 (Ex34)
at 20 and 30% PEI respectively, as determined according to
ISO5659-2 on a 3 mm thick plaque), which would make them suitable
for EN-45545 type applications (for R6 applications qualifying for
HL2 compliance, a smoke density (Ds-4) at or below 300 is
required), provided that the other required properties (e.g. heat
release) meet the requirements as well, whereas the combination of
polycarbonate homopolymer and a PC-siloxane without PEI does not
meet these requirements (Ds-4 value of about 720 (CEx31) as
determined according to ISO5659-2 on a 3 mm thick plaque, which
would fail to meet even HL-1, requiring Ds-4.ltoreq.600 for R6
applications).).
Examples 36-38
[0156] Examples 36-38 show that the addition of an aromatic
organophosphorus compound (BPADP) to compositions of PEI in a
polycarbonate copolymer results in a further unexpected combination
of properties. Results and formulations are shown in Table 11.
TABLE-US-00011 TABLE 11 CEx36 Ex37 CEX38 Component ITR-PC-siloxane
43.92 40.17 49.97 ITR-PC 43.92 40.17 49.97 PEPQ 0.06 0.06 0.06
Coated TiO.sub.2 2.00 2.00 2.0 Carbon black 0.10 0.10 0.10 BPADP 0
7.5 0 PEI 10 10 0 Properties DS-4 111 117 158 MAHRE 83 43 96
[0157] The results show that the combination of a
phosphorus-containing compound (BPADP) and PEI provides a
significant decrease in the MAHRE properties compared to the
composition without BPADP (with PEI in the formulation), lowering
from a MAHRE of 83 (CEx36) to 43 (Ex37), as determined according to
ISO5660-1 on a 3 mm thick plaque. The addition of the phosphorus
containing compound does not adversely affect smoke density (Ds-4),
with similar values with BPADP (Ds-4 of 111, CEx36) and without
BPADP (Ds-4 of 117, Ex37), all determined according to ISO5659-2 on
a 3 mm thick plaque.
[0158] The low heat release (MAHRE) and smoke density (Ds-4) make
the components capable of meeting the requirements of the most
strict hazard level (HL3) for R6 applications in European Railway
standard EN-45545, which requires MAHRE of equal to or less than
60, as determined according to ISO5660-1 on a 3 mm thick plaque,
and Ds-4 equal to or less than 150, as determined according to
ISO5659-2 on a 3 mm thick plaque.
[0159] Table 12 summarizes the interaction parameter values
obtained for the compositions showing the nonlinear effect of PEI
addition on smoke density of various polycarbonate copolymers and
their combinations.
TABLE-US-00012 TABLE 12 Composition Interaction Parameter (k)
ITR-PC 52.7 ITR-PC/ITR-PC-Si 16.4 PPPBP-PC 5.2 PC-Siloxane 16.6 PC
4.4 PC/PC-Siloxane 10.1
[0160] As shown in Table 12, where a nonlinear effect is observed,
the interaction parameter has a value of greater than 4. Using the
k interaction parameters, it is possible to calculate the
fractional concentration of PEI necessary to bring a given
thermoplastic composition to meet the various Hazard Levels under
EN 45545 European Rail standard (2013) requirements.
[0161] The singular forms "a," "an," and "the" include plural
referents unless the context clearly dictates otherwise. "Or" means
"and/or." The endpoints of all ranges directed to the same
component or property are inclusive and independently combinable.
The suffix "(s)" as used herein is intended to include both the
singular and the plural of the term that it modifies, thereby
including at least one of that term (e.g., "colorant(s)" includes
at least one colorant). "Optional" or "optionally" means that the
subsequently described event or circumstance can or cannot occur,
and that the description includes instances where the event occurs
and instances where it does not. Unless defined otherwise,
technical and scientific terms used herein have the same meaning as
is commonly understood by one of skill in the art to which this
invention belongs.
[0162] As used herein, a "combination" is inclusive of blends,
mixtures, alloys, reaction products, and the like. Compounds are
described using standard nomenclature. For example, any position
not substituted by any indicated group is understood to have its
valency filled by a bond as indicated, or a hydrogen atom. A dash
("-") that is not between two letters or symbols is used to
indicate a point of attachment for a substituent. For example,
--CHO is attached through carbon of the carbonyl group.
[0163] As used herein, the term "hydrocarbyl" and "hydrocarbon"
refers broadly to a substituent comprising carbon and hydrogen,
optionally with 1 to 3 heteroatoms, for example, oxygen, nitrogen,
halogen, silicon, sulfur, or a combination thereof; "alkyl" refers
to a straight or branched chain, saturated monovalent hydrocarbon
group; "alkylene" refers to a straight or branched chain,
saturated, divalent hydrocarbon group; "alkylidene" refers to a
straight or branched chain, saturated divalent hydrocarbon group,
with both valences on a single common carbon atom; "alkenyl" refers
to a straight or branched chain monovalent hydrocarbon group having
at least two carbons joined by a carbon-carbon double bond;
"cycloalkyl" refers to a non-aromatic monovalent monocyclic or
multicylic hydrocarbon group having at least three carbon atoms,
"cycloalkenyl" refers to a non-aromatic cyclic divalent hydrocarbon
group having at least three carbon atoms, with at least one degree
of unsaturation; "aryl" refers to an aromatic monovalent group
containing only carbon in the aromatic ring or rings; "arylene"
refers to an aromatic divalent group containing only carbon in the
aromatic ring or rings; "alkylaryl" refers to an aryl group that
has been substituted with an alkyl group as defined above, with
4-methylphenyl being an exemplary alkylaryl group; "arylalkyl"
refers to an alkyl group that has been substituted with an aryl
group as defined above, with benzyl being an exemplary arylalkyl
group; "acyl" refers to an alkyl group as defined above with the
indicated number of carbon atoms attached through a carbonyl carbon
bridge (--C(.dbd.O)--); "alkoxy" refers to an alkyl group as
defined above with the indicated number of carbon atoms attached
through an oxygen bridge (--O--); and "aryloxy" refers to an aryl
group as defined above with the indicated number of carbon atoms
attached through an oxygen bridge (--O--).
[0164] Unless otherwise indicated, each of the foregoing groups can
be unsubstituted or substituted, provided that the substitution
does not significantly adversely affect synthesis, stability, or
use of the compound. The term "substituted" as used herein means
that at least one hydrogen on the designated atom or group is
replaced with another group, provided that the designated atom's
normal valence is not exceeded. When the substituent is oxo (i.e.,
.dbd.O), then two hydrogens on the atom are replaced. Combinations
of substituents and/or variables are permissible provided that the
substitutions do not significantly adversely affect synthesis or
use of the compound. Exemplary groups that can be present on a
"substituted" position include, but are not limited to, cyano;
hydroxyl; nitro; azido; alkanoyl (such as a C.sub.2-6 alkanoyl
group such as acyl); carboxamido; C.sub.1-6 or C.sub.1-3 alkyl,
cycloalkyl, alkenyl, and alkynyl (including groups having at least
one unsaturated linkages and from 2 to 8, or 2 to 6 carbon atoms);
C.sub.1-6 or C.sub.1-3 alkoxy groups; C.sub.6-10 aryloxy such as
phenoxy; C.sub.1-6 alkylthio; C.sub.1-6 or C.sub.1-3 alkylsulfinyl;
C1-6 or C.sub.1-3 alkylsulfonyl; aminodi(C.sub.1-6 or
C.sub.1-3)alkyl; C.sub.6-12 aryl having at least one aromatic rings
(e.g., phenyl, biphenyl, naphthyl, or the like, each ring either
substituted or unsubstituted aromatic); C.sub.7-19 alkylenearyl
having 1 to 3 separate or fused rings and from 6 to 18 ring carbon
atoms, with benzyl being an exemplary arylalkyl group; or
arylalkoxy having 1 to 3 separate or fused rings and from 6 to 18
ring carbon atoms, with benzyloxy being an exemplary arylalkoxy
group.
[0165] All references cited herein are incorporated by reference in
their entirety. While typical embodiments have been set forth for
the purpose of illustration, the foregoing descriptions should not
be deemed to be a limitation on the scope herein. Accordingly,
various modifications, adaptations, and alternatives can occur to
one skilled in the art without departing from the spirit and scope
herein.
* * * * *