U.S. patent application number 09/882619 was filed with the patent office on 2002-04-18 for thermoplastic compositions of interpolymers of alpha-olefin monomers with one or more vinyl or vinylidene aromatic monomers and/or one or more hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers blended with engineering thermoplastics.
This patent application is currently assigned to The Dow Chemical Company. Invention is credited to Diehl, Charles F., Hoenig, Wendy D., Novak, Leo A., Ogoe, Samuel A., Scott, Danna C., Wu, Shaofu.
Application Number | 20020045685 09/882619 |
Document ID | / |
Family ID | 22139366 |
Filed Date | 2002-04-18 |
United States Patent
Application |
20020045685 |
Kind Code |
A1 |
Ogoe, Samuel A. ; et
al. |
April 18, 2002 |
Thermoplastic compositions of interpolymers of alpha-olefin
monomers with one or more vinyl or vinylidene aromatic monomers
and/or one or more hindered aliphatic or cycloaliphatic vinyl or
vinylidene monomers blended with engineering thermoplastics
Abstract
The present invention relates to a blend of polymeric materials
comprising; (A) of from about 1 to about 80 percent by weight
(based on the combined weights of Components A and B) of at least
one substantially random interpolymer; wherein said interpolymer;
(1) contains of from about 0.5 to about 50 mole percent of polymer
units derived from; a) at least one vinyl or vinylidene aromatic
monomer, or b) at least one hindered aliphatic or cycloaliphatic
vinyl or vinylidene monomer, or c) a combination of at least one
vinyl or vinylidene aromatic monomer and at least one hindered
aliphatic or cycloaliphatic vinyl or vinylidene monomer; (2)
contains of from about 50 to about 99.5 mole percent of polymer
units derived from at least one aliphatic .alpha.-olefin having
from 2 to 20 carbon atoms; (3) has a melt index (I.sub.2) of from
about 0.01 to about 100 g/10 min; and (4) has a molecular weight
distribution (M.sub.w/M.sub.n) of from about 1.5 to about 20; (B)
of from about 20 to about 99 weight percent based on the combined
weights of Components A, and B of one or more engineering
thermoplastics.
Inventors: |
Ogoe, Samuel A.; (Missouri
City, TX) ; Diehl, Charles F.; (Lake Jackson, TX)
; Novak, Leo A.; (Lake Jackson, TX) ; Hoenig,
Wendy D.; (Lake Jackson, TX) ; Wu, Shaofu;
(Missouri City, TX) ; Scott, Danna C.; (Brazoria,
TX) |
Correspondence
Address: |
J. Benjamin Bai, Ph.D.
Jenkens & Gilchrist
A Professional Corporation
1100 Louisiana, Ste. 1800
Houston
TX
77002-5214
US
|
Assignee: |
The Dow Chemical Company
|
Family ID: |
22139366 |
Appl. No.: |
09/882619 |
Filed: |
July 24, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09882619 |
Jul 24, 2001 |
|
|
|
09260450 |
Mar 2, 1999 |
|
|
|
60077663 |
Mar 11, 1998 |
|
|
|
Current U.S.
Class: |
524/35 |
Current CPC
Class: |
C08L 23/0815 20130101;
C08L 77/02 20130101; C08L 79/08 20130101; C08L 69/00 20130101; C08L
101/00 20130101; C08L 23/0838 20130101; C08L 77/00 20130101; C08L
67/03 20130101; C08L 23/16 20130101; C08L 67/02 20130101; C08L
23/08 20130101; C08L 23/0846 20130101; C08L 2314/06 20130101; C08L
77/06 20130101; C08L 23/08 20130101; C08L 2666/04 20130101; C08L
67/02 20130101; C08L 23/00 20130101; C08L 67/03 20130101; C08L
23/00 20130101; C08L 69/00 20130101; C08L 23/00 20130101; C08L
77/00 20130101; C08L 23/00 20130101; C08L 77/02 20130101; C08L
23/00 20130101; C08L 77/06 20130101; C08L 23/00 20130101; C08L
79/08 20130101; C08L 23/00 20130101; C08L 23/08 20130101; C08L
2666/14 20130101 |
Class at
Publication: |
524/35 |
International
Class: |
C08L 001/00 |
Claims
What is claimed is:
1. A blend of polymeric materials comprising (A) of from about 1 to
about 80 percent by weight (based on the combined weights of
Components A and B) of at least one substantially random
interpolymer; wherein said interpolymer; (1) contains of from about
0.5 to about 50 mole percent of polymer units derived from; a) at
least one vinyl or vinylidene aromatic monomer, or b) at least one
hindered aliphatic or cycloaliphatic vinyl or vinylidene monomer,
or c) a combination of at least one vinyl or vinylidene aromatic
monomer and at least one hindered aliphatic or cycloaliphatic vinyl
or vinylidene monomer; (2) contains of from about 50 to about 99.5
mole percent of polymer units derived from at least one aliphatic
.alpha.-olefin having from 2 to 20 carbon atoms; (3) has a melt
index (I.sub.2) of from about 0.01 to about 100 g/10 min; and (4)
has a molecular weight distribution (M.sub.w/M.sub.n) of from about
1.5 to about 20; (B) of from about 20 to about 99 weight percent
based on the combined weights of Components A, and B of one or more
engineering thermoplastics.
2. The blend of claim 1 wherein; (1) Component A is present in an
amount of from about 1 to about 65 percent by weight (based on the
combined weights of Components A and B); (2) Component A contains
of from about 20 to about 50 mole percent of polymer units derived
from; a) at least one of said vinyl or vinylidene aromatic
monomers, Component A(1)(a), represented by the following general
formula; 8 wherein R.sup.1 is selected from the group of radicals
consisting of hydrogen and alkyl radicals containing from 1 to
about 4 carbon atoms, preferably hydrogen or methyl; each R.sup.2
is independently selected from the group of radicals consisting of
hydrogen and alkyl radicals containing from 1 to about 4 carbon
atoms, preferably hydrogen or methyl; Ar is a phenyl group or a
phenyl group substituted with from 1 to 5 substituents selected
from the group consisting of halo, C.sub.1-4-alkyl, and
C.sub.1-4-haloalkyl; and n has a value from zero to about 4; or b)
at least one of said hindered aliphatic or cycloaliphatic vinyl or
vinylidene monomers, Component A(1)(b), represented by the
following general formula; 9 wherein A.sup.1 is a sterically bulky,
aliphatic or cycloaliphatic substituent of up to 20 carbons,
R.sup.1 is selected from the group of radicals consisting of
hydrogen and alkyl radicals containing from 1 to about 4 carbon
atoms, preferably hydrogen or methyl; each R.sup.2 is independently
selected from the group of radicals consisting of hydrogen and
alkyl radicals containing from 1 to about 4 carbon atoms,
preferably hydrogen or methyl; or alternatively R.sup.1 and A.sup.1
together form a ring system; or (c) a combination of at least one
of said vinyl or vinylidene aromatic monomer and at least one of
said hindered aliphatic or cycloaliphatic vinyl or vinylidene
monomer; (3) Component A contains of from about 50 to about 80 mole
percent of polymer units derived from at least one of said
aliphatic .alpha.-olefins selected from the group consisting of
ethylene or a combination of ethylene and at least one of
propylene, 4-methyl pentene, butene-1, hexene-1 or octene-1; (4)
Component A has a melt index (I.sub.2) of from about 0.01 to about
10 g/10 min; (5) Component A has a molecular weight distribution
(M.sub.w/M.sub.n) of from about 1.8 to about 10; and (6) Component
B is present in an amount of from about 35 to about 99 weight
percent based on the combined weights of components A, and B and
comprises acetal resins, acrylic resins, polyamides,nylon-6, nylon
6,6, polyimides, polyetherimides, cellulosics, polyesters,
poly(arylate), aromatic polyesters, poly(carbonate), poly(butylene)
and polybutylene and polyethylene terephthalates, polyethers,
polycyclopentanes, and its copolymers, polymethylpentane,
poly(carbonate), polyethylene terephthalate or polybutylene
terephthalate; (7) Component B has a molecular weight (Mw) of from
about 10,000 to about 40,000; and (8) has a melt flow rate (MFR) of
from about 2 to about 80 g/10 min.
3. The blend of claim 1 wherein; (1) Component A is present in an
amount of from about 1 to about 50 percent by weight (based on the
combined weights of Components A and B); (2) Component A contains
of from about 30 to about 45 mole percent of polymer units derived
from; a) said vinyl or vinylidene aromatic monomer which comprises
styrene, .alpha.-methyl styrene, ortho-, meta-, and
para-methylstyrene, and the ring halogenated styrenes, or b) said
hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers
which comprises 5-ethylidene-2-norbornene or 1-vinylcyclo-hexene,
3-vinylcyclo-hexene, and 4-vinylcyclohexene; or c) a combination of
at least one of a) and b); (3) Component A contains of from about
55 to about 70 mole percent of polymer units derived from said
.alpha.-olefin, which comprises ethylene, or ethylene and at least
one of propylene, 4-methyl-1-pentene, butene-1, hexene-1 or
octene-1; or (4) Component A has a melt index (I.sub.2) of from
about 0.01 to about 5 g/1 min; (5) Component A has a molecular
weight distribution (M.sub.w/M.sub.n) of from about 2 to about 5;
and (6) Component B is present in an amount of from about 50 to
about 99 percent by weight (based on the combined weights of
Components A and B) and comprises poly(carbonate), polyethylene
terephthalate or polybutylene terephthalate; (7) Component B has a
molecular weight (Mw) of from about 15,000 to about 38,000; and (8)
has a melt flow rate (MFR) of from about 4 to about 30 g/10
min.
4. A blend of claim 3 wherein i) said vinyl or vinylidene aromatic
monomer, Component A1(a), is styrene; ii) said aliphatic
.alpha.-olefin, Component A2, is ethylene; iii) said, Component B,
is poly(carbonate).
5. A blend of claim 3 wherein i) said vinyl or vinylidene aromatic
monomer, Component A1(a), is styrene; ii) said aliphatic
.alpha.-olefin, Component A2, is ethylene; iii) said Component B,
is poly(carbonate).
6. The blend of claim 1 further comprising a filler.
7. The blend of claim 1 further comprising one or more ignition
resistance additives selected from halogenated hydrocarbons,
halogenated carbonate oligomers, halogenated diglycidyl ethers,
organophosphorous compounds, fluorinated olefins, antimony oxide
and metal salts of aromatic sulfur compounds.
8. A blend of claim 1 wherein Component A is produced by
polymerization in the presence of a metallocene or constrained
geometry catalyst and a co-catalyst.
9. A blend of claim 1 in the form of a molded or extruded
article.
10. A blend of claim 2 in the form of a molded or extruded
article.
11. A blend of claim 3 in the form of a molded or extruded
article.
12. A blend of claim 4 in the form of a molded or extruded
article.
13. A blend of claim 5 in the form of a molded or extruded
article.
14. A blend of claim 6 in the form of a molded or extruded
article.
15. A blend of claim 7 in the form of a molded or extruded
article.
16. A blend of claim 8 in the form of a molded or extruded
article.
17. The blend of claim 1 further comprising (C) of from about 15 to
about 30 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more polyolefin elastomers
wherein said polyolefin elastomer; (1) has a melt index (I.sub.2)
of from about 0.01 to about 100 g/10 min; and (2) has a density of
from about 0.860 to about 0.900 g/cm.sup.3; and (D) of from about
0.5 to about 20 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more functional
polyolefins.
18. The blend of claim 1 further comprising (C) of from about 10 to
about 20 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more polyolefin elastomers
wherein said polyolefin elastomer; (1) has a melt index (I.sub.2)
of from about 0.1 to about 10 g/10 min; and (2) has a density of
from about 0.860 to about 0.895 g/cm.sup.3; and (D) of from about
0.5 to about 15 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more functional
polyolefins.
19. The blend of claim 1 further comprising (C) of from about 3 to
about 15 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more polyolefin elastomers
wherein said polyolefin elastomer; (1) has a melt index (I.sub.2)
of from about 0.25 to about 5.0 g/10 min; and (2) has a density of
from about 0.860 to about 0.885 g/cm.sup.3; and (D) of from about
1.0 to about 10 percent by weight (based on the combined weights of
Components A, B, C, and D) of one or more functional
polyolefins.
20. A blend of claim 17 in the form of a molded or extruded
article.
21. A blend of claim 18 in the form of a molded or extruded
article.
22. A blend of claim 19 in the form of a molded or extruded
article.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of US provisional
application number 60/077,663 filed on Mar. 11, 1998.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] This invention relates to thermoplastic compositions of
interpolymers of .alpha.-olefin monomers with one or more vinyl or
vinylidene aromatic monomers and/or one or more hindered aliphatic
or cycloaliphatic vinyl or vinylidene monomers blended with one or
more engineering thermoplastics.
[0004] The generic class of materials of .alpha.-olefin/hindered
vinyl or vinylidene monomer substantially random interpolymers,
including materials such as .alpha.-olefin/vinyl aromatic monomer
interpolymers, and their preparation, are known in the art, such as
described in EP 416 815 A2. These materials, such as
ethylene/styrene interpolymers, offer a wide range of material
structures and properties which makes them useful for varied
applications, such as asphalt modifiers or as compatibilizers for
blends of polyethylene and polystyrene, as described in U.S. Pat.
No. 5,460,818.
[0005] The structure, thermal transitions and mechanical properties
of substantially random interpolymers of ethylene and styrene
containing up to about 50 mole percent styrene have been described
(Y. W. Cheung, M. J. Guest; Proc. Antec '96 pages 1634-1637). These
polymers are found to have glass transitions in the range
-20.degree. C. to +35.degree. C., and show no measurable
crystallinity above about 25 mole percent styrene incorporation,
i.e. they are essentially amorphous.
[0006] Engineering thermoplastics are defined in the third edition
of the Kirk-Othmer Encyclopedia of Science and Technology as
thermoplastic resins, neat or unreinforced or filled, which
maintain dimensional stability and most mechanical properties above
100.degree. C. and below 0.degree. C. Thermoplastics such as
polycarbonate have found many uses because, in general, they
combine a high level of heat resistance toughness and dimensional
stability with good insulating and non-corrosive properties, and
are easily molded. Polycarbonate does however, suffer from a
tendency to craze and crack under the effect of contact with
organic solvents such as gasoline. An undesirable result in
polycarbonate which has crazed is that it is more likely to
experience brittle rather than ductile failure.
[0007] This disadvantage has been somewhat relieved by the practice
of blending polycarbonate with various olefin polymers such as low
density polyethylene or linear low density polyethylene, or
thermoplastic rubbers such as ethylene/propylene copolymer These
added substances are capable of improving the resistance of
polycarbonate to solvents, but they tend to delaminate and cause an
offsetting reduction in the toughness, impact resistance and
weldline strength of the blended polycarbonate composition. Such
delamination, and the resulting loss of utility, is reported, for
example, in U.S. Pat. No. 4,496,693. In addition such
polycarbonate/olefin polymer blends show high gloss, significant
pearlescence, as well as solid opaque appearance.
[0008] In many automotive interior applications, such as instrument
panel, head impact and interior trim, thermoplastic resins having
good impact resistance, colorability and aesthetically pleasing
attributes are essential.
[0009] Impact resistance in polycarbonate can be improved by the
incorporation of emulsion or core-shell elastomers such as
methacrylate/butadiene/styrene copolymer or a butyl acrylate
rubber. However, these core-shell rubbers hinder processability of
the blend by increasing viscosity. It would accordingly be
desirable if modifers blended with polycarbonate for the purpose of
improving its impact resistance did not also deleteriously affect
its processability, and cause delamination as evidenced by peeling
or splintering in a molded article.
[0010] The purpose of this invention is to provide novel blend
compositions comprising one or more engineering thermoplastics and
at least one substantially random interpolymer of one or more
.alpha.-olefin monomers with one or more vinyl or vinylidene
aromatic monomers and/or one or more hindered aliphatic or
cycloaliphatic vinyl or vinylidene monomers.
[0011] The blend compositions can exhibit a unique balance of
properties including high heat distortion temperature, excellent
miscibility with no delamination and no pearlescence, excellent
processability and good colorability when injection molded into
various parts. In addition when the substantially random
interpolymer component of the blend has high levels of vinyl or
vinylidene aromatic monomer or hindered aliphatic or cycloaliphatic
vinyl or vinylidene monomer content (greater than about 36 mol %)
then enhanced optical properties are observed including diminishing
opacity and the generation of an almost translucent appearance in
the fabricated part.
[0012] As a further embodiment, the invention provides novel blend
compositions comprising one or more engineering thermoplastics, and
at least one substantially random interpolymer of one or more
.alpha.-olefin monomers with one or more vinyl or vinylidene
aromatic monomers and/or one or more hindered aliphatic or
cycloaliphatic vinyl or vinylidene monomers in combination with one
or more polyolefin elastomers and one or more ethylene-methyl
acrylate-glycidyl methacrylate-styrene acrylonitrile multi polymer
blends.
[0013] These blend compositions allow for the manufacture of
PC/polyolefin compositions during extrusion which exhibit good low
temperature toughness and impact strength and for which the
processability and colorability is significantly improved via
addition of one or more substantially random interpolymers of one
or more .alpha.-olefin monomers with one or more vinyl or
vinylidene aromatic monomers and/or one or more hindered aliphatic
or cycloaliphatic vinyl or vinylidene monomers . Such blend
compositions additionally find utility in many automotive interior
parts, involving, for example, instrument panel, head impact and
interior trim applications.
BRIEF SUMMARY OF THE INVENTION
[0014] The present invention relates to a blend of polymeric
materials comprising;
[0015] (A) of from about 1 to about 80 percent by weight (based on
the combined weights of Components A and B) of at least one
substantially random interpolymer; wherein said interpolymer;
[0016] (1) contains of from about 0.5 to about 50 mole percent of
polymer units derived from;
[0017] a) at least one vinyl or vinylidene aromatic monomer, or
[0018] b) at least one hindered aliphatic or cycloaliphatic vinyl
or vinylidene monomer, or
[0019] c) a combination of at least one vinyl or vinylidene
aromatic monomer and at least one hindered aliphatic or
cycloaliphatic vinyl or vinylidene monomer;
[0020] (2) contains of from about 50 to about 99.5 mole percent of
polymer units derived from at least one aliphatic .alpha.-olefin
having from 2 to 20 carbon atoms;
[0021] (3) has a meltindex (I.sub.2) of from about 0.01 to about
100 g/10 min; and
[0022] (4) has a molecular weight distribution (M.sub.w/M.sub.n) of
from about 1.5 to about 20;
[0023] (B) of from about 20 to about 99 weight percent based on the
combined weights of Components A, and B of one or more engineering
thermoplastics.
[0024] The compositions of the present invention, can be utilized
to produce a wide range of fabricated articles such as, for
example, calendered, cast and blown sheets and films, extruded
parts, blow molded parts, injection molded parts, and the like. The
compositions of the present invention can further find utility in
flexible molded goods, as layers in multilayer film structures, in
applications such as automotive instrument panel skins.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Definitions
[0026] All references herein to elements or metals belonging to a
certain Group refer to the Periodic Table of the Elements published
and copyrighted by CRC Press, Inc., 1989. Also any reference to the
Group or Groups shall be to the Group or Groups as reflected in
this Periodic Table of the Elements using the IUPAC system for
numbering groups.
[0027] Any numerical values recited herein include all values from
the lower value to the upper value in increments of one unit
provided that there is a separation of at least 2 units between any
lower value and any higher value. As an example, if it is stated
that the amount of a component or a value of a process variable
such as, for example, temperature, pressure, time and the like is,
for example, from 1 to 90, preferably from 20 to 80, more
preferably from 30 to 70, it is intended that values such as 15 to
85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in
this specification. For values which are less than one, one unit is
considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate. These
are only examples of what is specifically intended and all possible
combinations of numerical values between the lowest value and the
highest value enumerated are to be considered to be expressly
stated in this application in a similar manner.
[0028] The term "hydrocarbyl" as employed herein means any
aliphatic, cycloaliphatic, aromatic, aryl substituted aliphatic,
aryl substituted cycloaliphatic, aliphatic substituted aromatic, or
aliphatic substituted cycloaliphatic groups.
[0029] The term "hydrocarbyloxy" means a hydrocarbyl group having
an oxygen linkage between it and the carbon atom to which it is
attached.
[0030] The term "interpolymer" is used herein to indicate a polymer
wherein at least two different monomers are polymerized to make the
interpolymer. This includes copolymers, terpolymers, etc.
[0031] The term "substantially random" in the substantially random
interpolymer comprising an .alpha.-olefin and a vinyl or vinylidene
aromatic monomer or hindered aliphatic or cycloaliphatic vinyl or
vinylidene monomer as used herein means that the distribution of
the monomers of said interpolymer can be described by the Bernoulli
statistical model or by a first or second order Markovian
statistical model, as described by J. C. Randall in POLYMER
SEQUENCE DETERMINATION, Carbon-13 NMR Method, Academic Press New
York, 1977, pp. 71-78. Preferably, the substantially random
interpolymer comprising an .alpha.-olefin and a vinyl or vinylidene
aromatic monomer does not contain more than 15 percent of the total
amount of vinyl or vinylidene aromatic monomer in blocks of vinyl
or vinylidene aromatic monomer of more than 3 units. More
preferably, the interpolymer was not characterized by a high degree
of either isotacticity or syndiotacticity. This means that in the
carbon.sup.-13 NMR spectrum of the substantially random
interpolymer the peak areas corresponding to the main chain
methylene and methine carbons representing either meso diad
sequences or racemic diad sequences should not exceed 75 percent of
the total peak area of the main chain methylene and methine
carbons.
[0032] The Substantially Random .alpha.-Olefin/ Vinyl or Vinylidene
Aromatic or Hindered Aliphatic or Cycloaliphatic Vinyl or
Vinylidene Interpolymer
[0033] The substantially random interpolymers are prepared by
polymerizing one or more .alpha.-olefins with one or more vinyl or
vinylidene aromatic monomers and/or one or more hindered aliphatic
or cycloaliphatic vinyl or vinylidene monomers, and optionally
other polymerizable monomers.
[0034] Suitable .alpha.-olefins include for example,
.alpha.-olefins containing from 2 to about 20, preferably from 2 to
about 12, more preferably from 2 to about 8 carbon atoms.
Particularly suitable are ethylene, propylene,
butene-1,4-methyl-1-pentene, hexene-1 and octene-1. These
.alpha.-olefins do not contain an aromatic moiety.
[0035] Suitable vinyl or vinylidene aromatic monomers which can be
employed to prepare the interpolymers include, for example, those
represented by the following formula: 1
[0036] wherein R.sup.1 is selected from the group of radicals
consisting of hydrogen and alkyl radicals containing from 1 to
about 4 carbon atoms, preferably hydrogen or methyl; each R.sup.2
is independently selected from the group of radicals consisting of
hydrogen and alkyl radicals containing from 1 to about 4 carbon
atoms, preferably hydrogen or methyl; Ar is a phenyl group or a
phenyl group substituted with from 1 to 5 substituents selected
from the group consisting of halo, C.sub.1-4-alkyl, and
C.sub.1-4-haloalkyl; and n has a value from zero to about 4,
preferably from zero to 2, most preferably zero. Exemplary vinyl
aromatic monomers include styrene, vinyl toluene,
.alpha.-methylstyrene, t-butyl styrene, chlorostyrene, including
all isomers of these compounds, and the like. Particularly suitable
such monomers include styrene and lower alkyl- or
halogen-substituted derivatives thereof Preferred monomers include
styrene, .alpha.-methyl styrene, the lower alkyl-(C.sub.1-C.sub.4)
or phenyl-ring substituted derivatives of styrene, such as for
example, ortho-, meta-, and para-methylstyrene, the ring
halogenated styrenes, para-vinyl toluene or mixtures thereof, and
the like. A more preferred aromatic vinyl monomer is styrene.
[0037] By the term "hindered aliphatic or cycloaliphatic vinyl or
vinylidene compounds", it is meant addition polymerizable vinyl or
vinylidene monomers corresponding to the formula: 2
[0038] wherein A.sup.1 is a sterically bulky, aliphatic or
cycloaliphatic substituent of up to 20 carbons, R.sup.1 is selected
from the group of radicals consisting of hydrogen and alkyl
radicals containing from 1 to about 4 carbon atoms, preferably
hydrogen or methyl; each R.sup.2 is independently selected from the
group of radicals consisting of hydrogen and alkyl radicals
containing from 1 to about 4 carbon atoms, preferably hydrogen or
methyl; or alternatively R.sup.1 and A.sup.1 together form a ring
system. By the term "sterically bulky" is meant that the monomer
bearing this substituent is normally incapable of addition
polymerization by standard Ziegler-Natta polymerization catalysts
at a rate comparable with ethylene polymerizations. Preferred
hindered aliphatic or cycloaliphatic vinyl or vinylidene compounds
are monomers in which one of the carbon atoms bearing ethylenic
unsaturation is tertiary or quaternary substituted. Examples of
such substituents include cyclic aliphatic groups such as
cyclohexyl, cyclohexenyl, cyclooctenyl, or ring alkyl or aryl
substituted derivatives thereof, tert-butyl, norbornyl, and the
like. Most preferred hindered aliphatic or cycloaliphatic vinyl or
vinylidene compounds are the various isomeric vinyl-ring
substituted derivatives of cyclohexene and substituted
cyclohexenes, and 5-ethylidene-2-norbornene. Especially suitable
are 1-, 3-, and 4-vinylcyclohexene. The linear .alpha.-olefins
containing from 2 to about 20 carbon atoms such as ethylene,
propylene, butene-1,4-methyl-1-pentene, hexene-1 and octene-1 are
not examples of hindered aliphatic or cycloaliphatic vinyl or
vinylidene compounds.
[0039] Other optional polymerizable ethylenically unsaturated
monomer(s) include strained ring olefins such as norbomene and
C.sub.1-10 alkyl or C.sub.6-10 aryl substituted norbornenes, with
an exemplary interpolymer being ethylene/styrene/norbornene.
[0040] The substantially random interpolymers may be modified by
typical grafting, hydrogenation, functionalizing, or other
reactions well known to those skilled in the art. The polymers may
be readily sulfonated or chlorinated to provide functionalized
derivatives according to established techniques.
[0041] One method of preparation of the substantially random
interpolymers is by polymerization of a mixture of polymerizable
monomers in the presence of metallocene or constrained geometry
catalysts and an activating cocatalyst.
[0042] The substantially random interpolymers can be prepared as
described in EP-A-0,416,815 by James C. Stevens et al. and U. S.
Pat. No. 5,703,187 by Francis J. Timmers, both of which are
incorporated herein by reference in their entirety. Preferred
operating conditions for such polymerization reactions are
pressures from atmospheric up to 3000 atmospheres and temperatures
from -30.degree. C. to 200.degree. C. Polymerizations and unreacted
monomer removal at temperatures above the autopolymerization
temperature of the respective monomers may result in formation of
some amounts of homopolymer polymerization products for example the
production of atactic polystyrene.
[0043] Examples of suitable catalysts and methods for preparing the
substantially random interpolymers are disclosed in U.S.
application Ser. No. 702,475, filed May 20, 1991 (EP-A-514,828); as
well as U.S. Pat. Nos. 5,055,438; 5,057,475; 5,096,867; 5,064,802;
5,132,380; 5,189,192; 5,321,106; 5,347,024; 5,350,723; 5,374,696;
5,399,635; 5,470,993; 5,703,187; and 5,721,185 all of which patents
and applications are incorporated herein by reference.
[0044] The substantially random .alpha.-olefin/vinyl or vinylidene
aromatic interpolymers can also be prepared by the methods
described in JP 07/278230 employing compounds shown by the general
formula 3
[0045] where Cp.sup.1 and Cp.sup.2 are cyclopentadienyl groups,
indenyl groups, fluorenyl groups, or substituents of these,
independently of each other; R.sup.1 and R.sup.2 are hydrogen
atoms, halogen atoms, hydrocarbon groups with carbon numbers of
1-12, alkoxy groups, or aryloxy groups, independently of each
other; M is a group IV metal, preferably Zr or Hf, most preferably
Zr; and R.sup.3 is an alkylene group or silanediyl group used to
cross-link Cp.sup.1 and Cp.sup.2.
[0046] The substantially random .alpha.-olefin/vinyl or vinylidene
aromatic interpolymers can also be prepared by the methods
described by John G. Bradfute et al. (W. R. Grace & Co.) in WO
95/32095; by R. B. Pannell (Exxon Chemical Patents, Inc.) in WO
94/00500; and in Plastics Technology, p. 25 (September 1992), all
of which are incorporated herein by reference in their
entirety.
[0047] Also suitable are the substantially random interpolymers
which comprise at least one .alpha.-olefin/vinyl aromatic/vinyl
aromatic/.alpha.-olefin tetrad disclosed in U.S. Application No.
08/708,809 filed Sep. 4, 1996 and WO 98/09999 both by Francis J.
Timmers et al. These interpolymers contain additional signals in
their carbon.sup.-13 NMR spectra with intensities greater than
three times the peak to peak noise. These signals appear in the
chemical shift range 43.70-44.25 ppm and 38.0-38.5 ppm.
Specifically, major peaks are observed at 44.1, 43.9 and 38.2 ppm.
A proton test NMR experiment indicates that the signals in the
chemical shift region 43.70-44.25 ppm are methine carbons and the
signals in the region 38.0-38.5 ppm are methylene carbons.
[0048] It is believed that these new signals are due to sequences
involving two head-to-tail vinyl aromatic monomer insertions
preceded and followed by at least one .alpha.-olefin insertion,
e.g. an ethylene/styrene/styrene/ethylene tetrad wherein the
styrene monomer insertions of said tetrads occur exclusively in a
1,2 (head to tail) manner. It is understood by one skilled in the
art that for such tetrads involving a vinyl aromatic monomer other
than styrene and an .alpha.-olefin other than ethylene that the
ethylene/vinyl aromatic monomer/vinyl aromatic monomer/ethylene
tetrad will give rise to similar carbon.sup.-13 NMR peaks but with
slightly different chemical shifts.
[0049] These interpolymers are prepared by conducting the
polymerization at temperatures of from about -30.degree. C. to
about 250.degree. C. in the presence of such catalysts as those
represented by the formula 4
[0050] wherein: each Cp is independently, each occurrence, a
substituted cyclopentadienyl group .pi.-bound to M; E is C or Si; M
is a group IV metal, preferably Zr or Hf, most preferably Zr; each
R is independently, each occurrence, H, hydrocarbyl,
silahydrocarbyl, or hydrocarbylsilyl, containing up to about 30
preferably from 1 to about 20 more preferably from 1 to about 10
carbon or silicon atoms; each R' is independently, each occurrence,
H, halo, hydrocarbyl, hydrocarbyloxy, silahydrocarbyl,
hydrocarbylsilyl containing up to about 30 preferably from 1 to
about 20 more preferably from 1 to about 10 carbon or silicon atoms
or two R' groups together can be a C.sub.1-10 hydrocarbyl
substituted 1,3-butadiene; m is 1 or 2; and optionally, but
preferably in the presence of an activating cocatalyst.
Particularly, suitable substituted cyclopentadienyl groups include
those illustrated by the formula: 5
[0051] wherein each R is independently, each occurrence, H,
hydrocarbyl, silahydrocarbyl, or hydrocarbylsilyl, containing up to
about 30 preferably from 1 to about 20 more preferably from 1 to
about 10 carbon or silicon atoms or two R groups together form a
divalent derivative of such group. Preferably, R independently each
occurrence is (including where appropriate all isomers) hydrogen,
methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl, phenyl or
silyl or (where appropriate) two such R groups are linked together
forming a fused ring system such as indenyl, fluorenyl,
tetrahydroindenyl, tetrahydrofluorenyl, or octahydrofluorenyl.
[0052] Particularly preferred catalysts include, for example,
racemic-(dimethylsilanediyl-bis
-(2-methyl-4-phenylindenyl))zirconium dichloride,
racemic-(dimethylsilanediyl-bis-(2-methyl-4-phenylindenyl))zi-
rconium 1,4-diphenyl-1,3-butadiene, racemic-(dimethylsilanediyl-bis
-(2-methyl-4-phenylindenyl))zirconium di-C.sub.1-4 alkyl,
racemic-(dimethylsilanediyl
-bis-(2-methyl-4-phenylindenyl))zirconium di-C.sub.1-4
alkoxide.
[0053] Also included are the titanium-based constrained geometry
catalysts,
[N-(1,1-dimethylethyl)-1,1-dimethyl-1-[(1,2,3,4,5-.eta.)-1,5,6-
,7-tetrahydro-s-indacen-1-yl]silanaminato(2-)-N]titanium dimethyl;
(1-indenyl)(tert-butylamido)dimethyl-silane titanium dimethyl;
((3-tert-butyl)(1,2,3,4,5-)-1-indenyl)(tert-butylamido)
dimethylsilane titanium dimethyl; and
((3-iso-propyl)(1,2,3,4,5-.eta.) )-1-indenyl)(tert-butyl amido)
dimethylsilane titanium dimethyl, or any combination thereof and
the like.
[0054] Further preparative methods for the substantially random
.alpha.-olefin/vinyl or vinylidene aromatic interpolymers blend
components of the present invention have been described in the
literature. Longo and Grassi (Makromol. Chem., Volume 191, pages
2387 to 2396 [1990]) and D'Anniello et al. (Journal of Applied
Polymer Science, Volume 58, pages 1701-1706 [1995]) reported the
use of a catalytic system based on methylalumoxane (MAO) and
cyclopentadienyltitanium trichloride (CpTiCl.sub.3) to prepare an
ethylene-styrene copolymer. Xu and Lin (Polymer Preprints, Am.
Chem. Soc., Div. Polym. Chem.) Volume 35, pages 686,687 [1994])
have reported copolymerization using a
MgCl.sub.2/TiCl.sub.4/NdCl.sub.3/Al(iBu).sub.3 catalyst to give
random copolymers of styrene and propylene. Lu et al (Journal of
Applied Polymer Science, Volume 53, pages 1453 to 1460 [1994]) have
described the copolymerization of ethylene and styrene using a
TiCl.sub.4/NdCl.sub.3/Mg- Cl.sub.2/Al(Et).sub.3 catalyst. The
manufacture of .alpha.-olefin/vinyl aromatic monomer interpolymers
such as propylene/styrene and butene/styrene are described in U.S.
Pat. No. 5,244,996, issued to Mitsui Petrochemical Industries Ltd
or U.S. Pat. No. 5,652,315 also issued to Mitsui Petrochemical
Industries Ltd or as disclosed in DE 197 11 339 A1 to Denki KAGAKU
Kogyo KK. All the above methods disclosed for preparing the
interpolymer component are incorporated herein by reference.
[0055] While preparing the substantially random interpolymer, an
amount of atactic vinyl or vinylidene aromatic homopolymer may be
formed due to homopolymerization of the vinyl or vinylidene
aromatic monomer at elevated temperatures. The presence of vinyl or
vinylidene aromatic homopolymer is in general not detrimental for
the purposes of the present invention and can be tolerated. The
vinyl or vinylidene aromatic homopolymer may be separated from the
interpolymer, if desired, by extraction techniques such as
selective precipitation from solution with a non solvent for either
the interpolymer or the vinyl or vinylidene aromatic homopolymer.
For the purpose of the present invention it is preferred that no
more than 20 weight percent, preferably less than 15 weight percent
based on the total weight of the interpolymers of atactic vinyl or
vinylidene aromatic homopolymer is present.
[0056] Also included as interpolymer blend components are
C.sub.4-C.sub.7, isoolefin/para-alkylstyrene interpolymers which
are random copolymers of a C.sub.4 to C.sub.7 isomonoolefin, such
as isobutylene and a para-alkylstyrene comonomer, preferably
para-methylstyrene containing at least about 80%, more preferably
at least about 90% by weight of the para isomer. These
interpolymers also include functionalized interpolymers wherein at
least some of the alkyl substituent groups present in the styrene
monomer units contain halogen or some other functional group
incorporated by nucleophilic substitution of benzylic halogen with
other groups such as alkoxide, phenoxide, carboxylate, thiolate,
thioether, thiocarbamate, dithiocarbamate, thiourea, xanthate,
cyanide, malonate, amine, amide, carbazole, phthalamide, maleimide,
cyanate, and mixtures thereof Preferred materials may be
characterized as isobutylene interpolymers containing the following
monomer units randomly spaced along the polymer chain. These
functionalized isomonoolefin interpolymers and their method of
preparation are more particularly disclosed in U.S. Pat. No.
5,162,445, the complete disclosure of which is incorporated herein
by reference.
[0057] Most useful of such functionalized materials are
elastomeric, random interpolymers of isobutylene and
para-methylstyrene containing from about 0.5 to about 20 mole %
para-methylstyrene wherein up to about 60 mole % of the methyl
substituent groups present on the benzyl ring contain a bromine or
chlorine atom, preferably a bromine atom. These polymers have a
substantially homogeneous compositional distribution such that at
least 95% by weight of the polymer has a para-alkylstyrene content
within 10% of the average para-alkylstyrene content of the polymer.
More preferred polymers are also characterized by a narrow
molecular weight distribution (M.sub.w/M.sub.n) of less than about
5, more preferably less than about 2.5. a preferred viscosity
average molecular weight in the range of from about 200,000 up to
about 2,000,000, and a preferred number average molecular weight in
the range of from about 25,000 to about 750,000, as determined by
Gel Permeation Chromatography.
[0058] The interpolymers may be prepared by slurry polymerization
of the monomer mixture using a Lewis Acid catalyst followed by
halogenation, preferably bromination, in solution in the presence
of halogen and a radical initiator such as heat and/or light and/or
a chemical initiator.
[0059] Preferred interpolymers are brominated interpolymers which
generally contain from about 0.1 to about 5 mole % of
bromomethylgroups, most of which is monobromomethyl, with less than
0.05 mole % dibromomethyl substituents present in the copolymer.
More preferred interpolymers contain from about 0.05 up to about
2.5 wt % of bromine based on the weight of the interpolymer, most
preferably from about 0.05 to 0.75 wt % bromine, and are
substantially free of ring halogen or halogen in the polymer
backbone chain. These interpolymers their method of preparation,
their method of cure and graft or functionalized polymers derived
therefrom are more particularly disclosed in the above referenced
U.S. Pat. No. 5,162,445. Such interpolymers are commercially
available from Exxon Chemical under the tradename Exxpro.TM.
Speciality Elastomers.
[0060] The Engineering Thermoplastic
[0061] The terms "engineering plastics" and "engineering
thermoplastics", can be used interchangeably. Engineering
Thermoplastics include acetal and acrylic resins (e.g
polymethylmethacrylate, PMMA), polyamides (e.g. nylon-6, nylon
6,6,), polyimides, polyetherimides, cellulosics, polyesters,
poly(arylate), aromatic polyesters, poly(carbonate), poly(butylene)
and polybutylene and polyethylene terephthalates liquid crystal
polymers, and selected polyolefins, blends, or alloys of the
foregoing resins, and some examples from other resin types
(including e.g. polyethers) high temperature polyolefins such as
polycyclopentanes, its copolymers, and polymethylpentane.). Of
these especially preferred are poly(carbonate),
polymethylmethacrylate and the polybutylene and polyethylene
terephthalates.
[0062] a) Polycarbonates useful as the blending or molding polymer
can be prepared from a dihydroxy compound such as a bisphenol, and
a carbonate precursor such as a disubstituted carbonic acid
derivative, a haloformate (such as a bishaloformate of a glycol or
dihydroxy benzene), or a carbonate ester such as diphenyl carbonate
or a substituted derivative thereof These components are often
reacted by means of the phase boundary process in which the
dihydroxy compound is dissolved and deprotonated in an aqueous
alkaline solution to form bisphenolate and the carbonate precursor
is dissolved in an organic solvent.
[0063] These components are often reacted by means of a mixture
prepared initially from the aromatic dihydroxy compound, water and
a non-reactive organic solvent immiscible with water selected from
among those in which the carbonate precursor and polycarbonate
product are soluble. Representative solvents include chlorinated
hydrocarbons such as methylene chloride, 1,2-dichloroethane,
tetrachloroethane, chlorobenzene, and chloroform. Caustic soda or
other base is then added to the reaction mixture to adjust the pH
of the mixture to a level at which the dihydroxy compound is
activated to dianionic form.
[0064] A carbonate precursor is contacted with an agitated mixture
of the aqueous alkaline solution of the dihydroxy compound, and,
for such purpose, the carbonate precursor can be bubbled into the
reaction mixture in the form of a gas, or can be dissolved and
introduced in solution form. Carbonater precursor is typically used
in an amount of about 1.0 to 1.8, preferably about 1.2. to 1.5,
moles per mole of dihydroxy compound. The mixture is agitated in a
manner which is sufficient to disperse or suspend droplets of the
solvent containing the carbonate precursor in the aqueous alkaline
solution. Reaction between the organic and aqueous phases created
by such agitation yields the bis(carbonate precursor) ester of the
dihydroxy compound. For example, if the carbonate precursor is a
carbonyl halide such as phosgene, the products of this initial
phase of the process are monomers or oligomers which are either
mono- or dichloroformates, or contain a phenolate ion at each
terminus.
[0065] These intermediate mono- and oligocarbonates dissolve in the
organic solvent as they form, and they can then be condensed to a
higher molecular weight polycarbonate by contact with a coupling
catalyst of which the following are representative: a tertiary
amine such as triethyl amine and dimethyl amino pyridine.
[0066] Upon completion of polymerization, the organic and aqueous
phases are separated to allow purification of the organic phase and
recovery of the polycarbonate product therefrom. The organic phase
is washed as needed in a centrifuge with dilute base, water and/or
dilute acid until free of unreacted monomer, residual process
chemicals and/or other electrolytes. Recovery of the polycarbonate
product can be effected by spray drying, steam devolatilization,
direct devolatilization in a vented extruder, or precipitation by
use of an anti-solvent such as toluene, cyclohexane, heptane,
methanol, hexanol, or methyl ethyl ketone.
[0067] In the melt process for preparation of polycarbonate,
aromatic diesters of carbonic acid are condensed with an aromatic
dihydroxy compound in a transesterification reaction in the
presence of a basic catalyst. The reaction is typically run at
about 250.degree. C. to 300.degree. C. under vacuum at a
progressively reduced pressure of about 1 to 100 mmHg.
[0068] Polycarbonate can also be prepared in a homogeneous solution
through a process in which a carbonate precursor, such as phosgene,
is contacted with a solution containing an aromatic dihydroxy
compound, a chlorinated hydrocarbon solvent and a substance, such
as pyridine, for dimethyl aniline or Ca(OH).sub.2, which acts as
both acid acceptor and condensation catalyst.
[0069] Examples of some dihydroxy compounds suitable for the
preparation of polycarbonate include variously bridged, substituted
or unsubstituted aromatic dihydroxy compounds (or mixtures thereof)
represented by the formula: 6
[0070] wherein:
[0071] I) Z is (A) a divalent radical, of which all or different
portions can be (i) linear, branched, cyclic or bicyclic, (ii)
aliphatic or aromatic, and/or (iii) saturated or unsaturated, said
divalent radical being composed of 1-35 carbon atoms together with
up to five oxygen, nitrogen, sulfur, phosphorous and/or halogen
(such as fluorine, chlorine and/or bromine) atoms; or (B) S,
S.sub.2, SO, SO.sub.2, O or CO; or (C) a single bond;
[0072] II) each X is independently hydrogen, a halogen (such as
fluorine, chlorine and/or bromine), a C.sub.1-C.sub.12, preferably
C.sub.1-C.sub.8, linear or cyclic alkyl, aryl, alkaryl, aralkyl,
alkoxy or aryloxy radical, such as methyl, ethyl, isopropyl,
cyclopentyl, cyclohexyl, methoxy, ethoxy, benzyl, tolyl, xylyl,
phenoxy and/or xylynoxy; or a nitro or nitrile radical; and
[0073] (III) m is 0 or 1.
[0074] For example, the bridging radical represented by Z in the
above formula can be a C.sub.2-C.sub.30 alkyl, cycloalkyl,
alkylidene or cycloalkyidene radical, or two or more thereof
connected by an aromatic or ether linkage, or can be a carbon atom
to which is bonded one or more groups such as CH.sub.3,
C.sub.2H.sub.5, C.sub.3H.sub.7, n-C.sub.3H.sub.7, i-C.sub.3H.sub.7,
cyclohexyl, bicyclo[2.2.1]heptyl, benzyl, CF.sub.2, CF.sub.3
CCI.sub.3, CF.sub.2Cl, CN, (CH.sub.2).sub.2COOCH.sub.3, or
PO(OCH.sub.3).sub.2.
[0075] Representative examples of dihydroxy compounds of particular
interest are the bis(hydroxyphenyl)alkanes, the
bis(hydroxyphenyl)cycloal- kanes, the dihydroxydiphenyls and the
bis(hydroxyphenyl)sulfones, and in particular are
2,2-bis(4-hydroxyphenyl)propane ("Bisphenol-A" or "Bis-A");
2,2-bis(3,5-dihalo-4-hydroxyphenyl)propane ("Tetrahalo
Bisphenol-A") where the halogen can be fluorine, chlorine, bromine
or iodine, for example 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane
("Tetrabromo Bisphenol-A" or "TBBA");
2,2-bis(3,5-dialkyl-4-hydroxyphenyl- )propane ("Tetraalkyl
Bisphenol-A") where the alkyl can be methyl or ethyl, for example
2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane ("Tetramethyl
Bisphenol-A"); 1,1-bis(4-hydroxyphenyl)-1-phenyl ethane
("Bisphenol-AP" or "Bis-AP"); Bishydroxy phenyl fluorene; and
1,1-bis(4-hydroxyphenyl)cyclohexane.
[0076] Using a process such as is generally described above, a
polycarbonate product can be obtained having a weight average
molecular weight, as determined by light scattering or gel
permeation chromatography, of 8,000 to 200,000 and preferably
15,000 to 40,000, and/or a melt flow value of about 3 to 150,
preferably about 10 to 80 (as determined by ASTM Designation D
1238-89, Condition 300/1.2), although values outside these ranges
are permitted as well. Molecular weight can be controlled by
addition to the reaction mixture of a chain terminator which may be
selected from monofunctional substances such as phenols, carbonic
acid chlorides, or phenylchlorocarbonates.
[0077] A branched rather than linear polycarbonate molecule can be
obtained by adding to the reaction mixture a tri- or polyfunctional
monomer such as trisphenoxy ethane.
[0078] The preferred process of this invention is that in which an
aromatic polycarbonate is prepared. An aromatic polycarbonate is
defined herein with reference to the oxygen atoms, of the one or
more dihydroxy compounds present in the polycarbonate chain, which
are bonded to a carbonyl carbon of the carbonate precursor. In an
aromatic polycarbonate, all such oxygen atoms are bridged by a
dihydroxy compound residue some portion of which is an aromatic
ring.
[0079] Also included within the term "polycarbonate", as used
herein, are various copolycarbonates, certain of which can be
prepared by incorporating one or more different dihydroxy compounds
into the reaction mixture. When a dicarboxylic acid such
terephthalic acid or isophthalic acid (or an ester-forming
derivative thereof) or a hydroxycarboxylic acid is used in the
reaction mixture, or to form an oligomeric prepolymer, instead of
one of the "different" dihydroxy compounds mentioned above, a
poly(ester/carbonate) is obtained, which is discussed in greater
detail in Swart, U.S. Pat. No. 4,105,533. In a preferred
embodiment, the compositions of this invention exclude a
poly(ester/carbonate).
[0080] Copolycarbonates can also be prepared, for example, by
reaction of one or more dihydroxy compounds with a carbonate
precursor in the presence of a chlorine- or amino-terminated
polysiloxane, with a hydroxy-terminated poly(phenylene oxide) or
poly(methyl methacrylate), or with phosphonyl dichloride or an
aromatic ester of a phosphonic acid. Siloxane/carbonate block
terpolymers are discussed in greater detail in Paul, U.S. Pat. No.
4,596,970.
[0081] The methods generally described above for preparing
carbonate polymers suitable for use in the practice of this
invention are well known; for example, several methods are
discussed in detail in Schnell, U.S. Pat. No. 3,028,365; Glass,
U.S. Pat. No. 4,529,791; and Grigo, U.S. Pat. No. 4,677,162.
[0082] b) Polyesters may be made by the self-esterification of
hydroxycarboxylic acids, or by direct esterification, which
involves the step-growth reaction of a diol with a dicarboxylic
acid with the resulting elimination of water, giving a polyester
with an --[--AABB--]-- repeating unit. The reaction may be run in
bulk or in solution using an inert high boiling solvent such as
xylene or chlorobenzene with azeotropic removal of water.
[0083] Alternatively, but in like manner, ester-forming derivatives
of a dicarboxylic acid can be heated with a diol to obtain
polyesters in an ester interchange reaction. Suitable acid
derivatives for such purpose are alkyl esters, halides, salts or
anhydrides of the acid. Preparation of polyarylates, from a
bisphenol and an aromatic diacid, can be conducted in an
interfacial system which is essentially the same as that used for
the preparation of polycarbonate.
[0084] Polyesters can also be produced by a ring-opening reaction
of cyclic esters or C.sub.4-C.sub.7 lactones, for which organic
tertiary amine bases phosphines and alkali and alkaline earth
metals, hydrides and alkoxides can be used as initiators.
[0085] Suitable reactants for making the polyester used in this
invention, in addition to hydroxycarboxylic acids, are diols and
dicarboxylic acids either or both of which can be aliphatic or
aromatic. A polyester which is a poly(alkylene
alkanedicarboxylate), a poly(alkylene arylenedicarboxylate), a
poly(arylene alkanedicarboxylate), or a poly(arylene
arylenedicarboxylate) is therefore appropriate for use herein.
Alkyl portions of the polymer chain can be substituted with, for
example, halogens, C.sub.1-C.sub.8 alkoxy groups or C.sub.1-C.sub.8
alkyl side chains and can contain divalent heteroatomic groups
(such as --O--, --Si--, --S--or --SO.sub.2--) in the paraffinic
segment of the chain. The chain can also contain unsaturation and
C.sub.6-C.sub.10 non-aromatic rings. Aromatic rings can contain
substituents such as halogens, C.sub.1-C.sub.8 alkoxy or
C.sub.1-C.sub.8 alkyl groups, and can be joined to the polymer
backbone in any ring position and directly to the alcohol or acid
functionality or to intervening atoms.
[0086] Typical aliphatic diols used in ester formation are the
C.sub.2-C.sub.10 primary and secondary glycols, such as ethylene-,
propylene-, and butylene glycol. Alkanedicarboxylic acids
frequently used are oxalic acid, adipic acid and sebacic acid.
Diols which contain rings can be, for example, a 1,4-cyclohexylenyl
glycol or a 1,4-cyclohexane-dimethylene glycol, resorcinol,
hydroquinone, 4,4'-thiodiphenol, bis-(4-hydroxyphenyl)sulfone, a
dihydroxynaphthalene, a xylylene diol, or can be one of the many
bisphenols such as 2,2-bis-(4-hydroxyphenyl)propane. Aromatic
diacids include, for example, terephthalic acid, isophthalic acid,
naphthalenedicarboxylic acid, diphenyletherdicarboxylic acid,
diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid,
diphenoxyethanedicarboxylic acid.
[0087] In addition to polyesters formed from one diol and one
diacid only, the term "polyester" as used herein includes random,
patterned or block copolyesters, for example those formed from two
or more different diols and/or two or more different diacids,
and/or from other divalent heteroatomic groups. Mixtures of such
copolyesters, mixtures of polyesters derived from one diol and
diacid only, and mixtures of members from both of such groups, are
also all suitable for use in this invention, and are all included
in the term "polyester". For example, use of cyclohexanedimethanol
together with ethylene glycol in esterification with terephthalic
acid forms a clear, amorphous copolyester of particular interest.
Also contemplated are liquid crystalline polyesters derived from
mixtures of 4-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid;
or mixtures of terephthalic acid, 4-hydroxybenzoic acid and
ethylene glycol; or mixtures of terephthalic acid, 4-hydroxybenzoic
acid and 4,4'-dihydroxybiphenyl.
[0088] Aromatic polyesters, those prepared from an aromatic diacid,
such as the poly(alkylene arylenedicarboxylates) polyethylene
terephthalate and polybutylene terephthalate, or mixtures thereof,
are particularly useful in this invention. A polyester suitable for
use herein may have an intrinsic viscosity of about 0.4 to 1.2,
although values outside this range are permitted as well.
[0089] Methods and materials useful for the production of
polyesters, as described above, are discussed in greater detail in
Whinfield, U.S. Pat. No. 2,465,319, Pengilly, U.S. Pat. No.
3,047,539, Schwarz, U.S. Pat. No. 3,374,402, Russell, U.S. Pat. No.
3,756,986 and East, U.S. Pat. No. 4,393,191.
[0090] Most acrylic resins derive from the peroxide-catalyzed free
radical polymerization of methyl methacrylate (MMA) to make
polymethylmethacrylate (PMMA). As described by H. Luke in Modem
Plastics Encyclopedia, 1989, pps 20-21, MMA is usually
copolymerized with other acrylates such as methyl- or ethyl
acrylate using four basic polymerization processes, bulk,
suspension, emulsion and solution. Acrylics can also be modified
with various ingredients including styrene, butadiene, vinyl and
alkyl acrylates. Acrylics known as PMMA have ASTM grades and
specifications. Grades 5, 6 and 8 vary mainly in deflection
temperature under load (DTL) requirements. Grade 8 requires a
tensile strength of 9,000 psi vs 8,000 psi for Grades 5 and 6. The
DTL varies from a minimum requirement of 153.degree. F. to a
maximum of 189.degree. F., under a load of 264 p.s.i. Certain
grades have a DTL of 212.degree. F. Impact-modified grades range
from an Izod impact of 1.1 to 2.0 ft .lb/in for non-weatherable
transparent materials. The opaque impact-modified grades can have
Izod impact values as high as 5.0 ft lb/in.
[0091] The Polyolefin Elastomers
[0092] The polyolefin elastomer component of the blend can include,
but is not limited to one or more of the .alpha.-olefin
homopolymers and interpolymers comprising polypropylene,
propylene/C.sub.4-C.sub.20 .alpha.-olefin copolymers, polyethylene,
and ethylene/C.sub.3-C.sub.20 .alpha.-olefin copolymers, the
interpolymers can be either heterogeneous ethylene/.alpha.-olefin
interpolymers or homogeneous ethylene/.alpha.-olefin interpolymers,
including the substantially linear ethylene/.alpha.-olefin
interpolymers.
[0093] Homogeneous Ethylene/.alpha.-Olefin Interpolymers
[0094] The relatively recent introduction of metallocene-based
catalysts for ethylene/.alpha.-olefin polymerization has resulted
in the production of new ethylene interpolymers and new
requirements for compositions containing these materials. Such
polymers are known as homogeneous interpolymers and are
characterized by their narrower molecular weight and composition
distributions (defined as the weight percent of the polymer
molecules having a comonomer content within 50 percent of the
median total molar comonomer content) relative to, for example,
traditional Ziegler catalyzed heterogeneous polyolefin polymers.
Generally blown and cast film made with such polymers are tougher
and have better optical properties and heat sealability than film
made with Ziegler Natta catalyzed LLDPE. It is known that
metallocene LLDPE offers significant advantages over Ziegler Natta
produced LLDPE's in cast film for pallet wrap applications,
particularly improved on-pallet puncture resistance. Such
metallocene LLDPE's however have a significantly poorer
processability on the extruder than Ziegler Natta products.
[0095] The Substantially Linear Ethylene/.alpha.-Olefin
Polymers
[0096] The substantially linear ethylene/.alpha.-olefin polymers
and interpolymers of the present invention are herein defined as in
U.S. Pat. No. 5,272,236 and in U.S. Pat. No. 5,278,272 (Lai et
al.), the entire contents of which are incorporated by reference.
The substantially linear ethylene/.alpha.-olefin polymers are also
metallocene based homogeneous polymers, as the comonomer is
randomly distributed within a given interpolymer molecule and
wherein substantially all of the interpolymer molecules have the
same ethylene/comonomer ratio within that interpolymer. Such
polymers are unique however due to their excellent processability
and unique rheological properties and high melt elasticity and
resistance to melt fracture. These polymers can be successfully
prepared in a continuous polymerization process using the
constrained geometry metallocene catalyst systems.
[0097] The substantially linear ethylene/.alpha.-olefin polymers
and are those in which the comonomer is randomly distributed within
a given interpolymer molecule and wherein substantially all of the
interpolymer molecules have the same ethylene/comonomer ratio
within that interpolymer.
[0098] The term "substantially linear" ethylene/.alpha.-olefin
interpolymer means that the polymer backbone is substituted with
about 0.01 long chain branches/1000 carbons to about 3 long chain
branches/1000 carbons, more preferably from about 0.01 long chain
branches/1000 carbons to about 1 long chain branches/1000 carbons,
and especially from about 0.05 long chain branches/1000 carbons to
about 1 long chain branches/1000 carbons.
[0099] Long chain branching is defined herein as a chain length of
at least one carbon more than two carbons less than the total
number of carbons in the comonomer, for example, the long chain
branch of an ethylene/octene substantially linear ethylene
interpolymer is at least seven (7) carbons in length (i.e., 8
carbons less 2 equals 6 carbons plus one equals seven carbons long
chain branch length). The long chain branch can be as long as about
the same length as the length of the polymer back-bone. Long chain
branching is determined by using .sup.13C nuclear magnetic
resonance (NMR) spectroscopy and is quantified using the method of
Randall (Rev. Macromol. Chem. Phys., C29 (2&3), p. 285-297),
the disclosure of which is incorporated herein by reference. Long
chain branching, of course, is to be distinguished from short chain
branches which result solely from incorporation of the comonomer,
so for example the short chain branch of an ethylene/octene
substantially linear polymer is six carbons in length, while the
long chain branch for that same polymer is at least seven carbons
in length.
[0100] The "rheological processing index" (PI) is the apparent
viscosity (in kpoise) of a polymer measured by a gas extrusion
rheometer (GER). The gas extrusion rheometer is described by M.
Shida, R. N. Shroff and L. V. Cancio in Polymer Engineering
Science, Vol. 17, no. 11, p. 770 (1977), and in "Rheometers for
Molten Plastics" by John Dealy, published by Van Nostrand Reinhold
Co. (1982) on page 97-99, both publications of which are
incorporated by reference herein in their entirety. All GER
experiments are performed at a temperature of 190.degree. C., at
nitrogen pressures between 5250 to 500 psig using a 0.0296 inch
diameter, 20:1 L/D die with an entrance angle of 180.degree.. For
the substantially linear ethylene/.alpha.-olefin polymers described
herein, the PI is the apparent viscosity (in kpoise) of a material
measured by GER at an apparent shear stress of 2.15.times.10.sup.6
dyne/cm.sup.2. The novel substantially linear
ethylene/.alpha.-olefin interpolymers described herein preferably
have a PI in the range of about 0.01 kpoise to about 50 kpoise,
preferably about 15 kpoise or less. The novel substantially linear
ethylene/.alpha.-olefin polymers described herein have a PI less
than or equal to about 70 percent of the PI of a comparative linear
ethylene/.alpha.-olefin polymer at about the same I.sub.2 and
M.sub.w/M.sub.n.
[0101] An apparent shear stress vs. apparent shear rate plot is
used to identify the melt fracture phenomena. According to
Ramamurthy in Journal of Rheology, 30(2), 337-357, 1986, above a
certain critical flow rate, the observed extrudate irregularities
may be broadly classified into two main types: surface melt
fracture and gross melt fracture.
[0102] Surface melt fracture occurs under apparently steady flow
conditions and ranges in detail from loss of specular gloss to the
more severe form of "sharkskin". In this disclosure, the onset of
surface melt fracture (OSMF) is characterized at the beginning of
losing extrudate gloss at which the surface roughness of extrudate
can only be detected by 40.times. magnification. The critical shear
rate at onset of surface melt fracture for the substantially linear
ethylene/.alpha.-olefin interpolymers is at least 50 percent
greater than the critical shear rate at the onset of surface melt
fracture of a linear ethylene/.alpha.-olefin polymer having about
the same I.sub.2 and M.sub.w/M.sub.n, wherein "about the same" as
used herein means that each value is within 10 percent of the
comparative value of the comparative linear ethylene polymer.
[0103] Gross melt fracture occurs at unsteady flow conditions and
ranges in detail from regular (alternating rough and smooth,
helical, etc.) to random distortions. For commercial acceptability,
(e.g., in blown film products), surface defects should be minimal,
if not absent. The critical shear rate at onset of surface melt
fracture (OSMF) and onset of gross melt fracture (OGMF) will be
used herein based on the changes of surface roughness and
configurations of the extrudates extruded by a GER.
[0104] The substantially linear ethylene/.alpha.-olefin polymers
useful for forming the compositions described herein have
homogeneous branching distributions. That is, the polymers are
those in which the comonomer is randomly distributed within a given
interpolymer molecule and wherein substantially all of the
interpolymer molecules have the same ethylene/comonomer ratio
within that interpolymer. The homogeneity of the polymers is
typically described by the SCBDI (Short Chain Branch Distribution
Index) or CDBI (Composition Distribution Branch Index) and is
defined as the weight percent of the polymer molecules having a
comonomer content within 50 percent of the median total molar
comonomer content. The CDBI of a polymer is readily calculated from
data obtained from techniques known in the art, such as, for
example, temperature rising elution fractionation (abbreviated
herein as "TREF") as described, for example, in Wild et al, Journal
of Polymer Science, Pol. Phys. Ed., Vol. 20, p. 441 (1982), in U.S.
Pat. No. 4,798,081 (Hazlitt et al.), or as is described in USP
5,008,204 (Stehling), the disclosure of which is incorporated
herein by reference. The technique for calculating CDBI is
described in U.S. Pat. No. 5,322,728 (Davey et al. ) and in U.S.
Pat. No. 5,246,783 (Spenadel et al.). or in U.S. Pat. No. 5,089,321
(Chum et al.) the disclosures of all of which are incorporated
herein by reference. The SCBDI or CDBI for the substantially linear
olefin interpolymers used in the present invention is preferably
greater than about 30 percent, especially greater than about 50
percent. The substantially linear ethylene/.alpha.-olefin
interpolymers used in this invention essentially lack a measurable
"high density" fraction as measured by the TREF technique (i.e.,
the homogeneous ethylene/.alpha.-olefin interpolymers do not
contain a polymer fraction with a degree of branching less than or
equal to 2 methyls/1000 carbons). The substantially linear
ethylene/.alpha.-olefin polymers also do not contain any highly
short chain branched fraction (i.e., they do not contain a polymer
fraction with a degree of branching equal to or more than 30
methyls/1000 carbons).
[0105] The catalysts used to prepare the homogeneous interpolymers
for use as blend components in the present invention are
metallocene catalysts. These metallocene catalysts include the
bis(cyclopentadienyl)-catalyst systems and the
mono(cyclopentadienyl) Constrained Geometry catalyst systems (used
to prepare the substantially linear ethylene/.alpha.-olefin
polymers). Such constrained geometry metal complexes and methods
for their preparation are disclosed in U.S. application Ser. No.
545,403, filed Jul. 3, 1990 (EP-A-416,815); as well as U.S. Pat.
No. 5,721,185; U.S. Pat. No. 5,374,696; U.S. Pat. No. 5,470,993,
U.S. Pat. No. 5,055,438, U.S. Pat. No. 5,057,475, U.S. Pat. No.
5,096,867, U.S. Pat. No. 5,064,802, and U.S. Pat. No.
5,132,380.
[0106] In EP-A 418,044, published Mar. 20, 1991 (equivalent to U.S.
Ser. No. 07/758,654) certain cationic derivatives of the foregoing
constrained geometry catalysts that are highly useful as olefin
polymerization catalysts are disclosed and claimed. In U.S. Pat.
No. 5,453,410 combinations of cationic constrained geometry
catalysts with an alumoxane were disclosed as suitable olefin
polymerization catalysts. For the teachings contained therein, the
aforementioned pending United States Patent applications, issued
United States Patents and published European Patent Applications
are herein incorporated in their entirety by reference thereto.
[0107] 2) Heterogeneous Ethylene/.alpha.-Olefin Interpolymers
[0108] Heterogeneous interpolymers are differentiated from the
homogeneous interpolymers in that in the latter, substantially all
of the interpolymer molecules have the same ethylene/comQnomer
ratio within that interpolymer, whereas heterogeneous interpolymers
are those in which the interpolymer molecules do not have the same
ethylene/comonomer ratio. The term "broad composition distribution"
used herein describes the comonomer distribution for heterogeneous
interpolymers and means that the heterogeneous interpolymers have a
"linear" fraction and that the heterogeneous interpolymers have
multiple melting peaks (i.e., exhibit at least two distinct melting
peaks) by DSC. The heterogeneous interpolymers have a degree of
branching less than or equal to 2 methyls/1000 carbons in about 10
percent (by weight) or more, preferably more than about 15 percent
(by weight), and especially more than about 20 percent (by weight).
The heterogeneous interpolymers also have a degree of branching
equal to or greater than 25 methyls/1000 carbons in about 25
percent or less (by weight), preferably less than about 15 percent
(by weight), and especially less than about 10 percent (by
weight).
[0109] The Ziegler catalysts suitable for the preparation of the
heterogeneous component of the current invention are typical
supported, Ziegler-type catalysts which are particularly useful at
the high polymerization temperatures of the solution process.
Examples of such compositions are those derived from
organomagnesium compounds, alkyl halides or aluminum halides or
hydrogen chloride, and a transition metal compound. Examples of
such catalysts are described in U.S. Pat. No. 4,314,912 (Lowery,
Jr. et al.), U.S. Pat. No. 4,547,475 (Glass et al.), and U.S. Pat.
No. 4,612,300 (Coleman, III), the teachings of which are
incorporated herein by reference.
[0110] Suitable catalyst materials may also be derived from a inert
oxide supports and transition metal compounds. Examples of such
compositions suitable for use in the solution polymerization
process are described in U.S. Pat No. 5,420,090 (Spencer. et al.),
the teachings of which are incorporated herein by reference.
[0111] The heterogeneous polymer component can be an .alpha.-olefin
homopolymer preferably polyethylene or polypropylene, or,
preferably, an interpolymer of ethylene with at least one
C.sub.3-C.sub.20 .alpha.-olefin and/or C.sub.4-C.sub.18 diolefins.
Heterogeneous copolymers of ethylene and 1-octene are especially
preferred.
[0112] The Functional Polyolefins
[0113] Functional polyolefins are olefin interpolymers other than
those of the polyolefin elastomer and substantially random
interpolymer blend components described above. They typically
comprise interpolymers of an alpha olefin with one or more
ethylenically unsaturated monomers, of which the following are
exemplary: a C1-C8 vinyl compound such as vinyl acetate or; a C1-C8
alkyl acrylate such as methyl acrylate, ethyl acrylate or hexyl
acrylate; a C1-C8 alkyl methacrylate such as methyl methacrylate or
hexyl methacrylate; glycidyl methacrylate; acrylic or methacrylic
acid; and the like or a mixture of two or more thereof.
[0114] Of these, the preferred .alpha.-olefin is ethylene, and the
preferred ethylenically unsaturated monomers are methyl acrylate,
and glycidyl methacrylate. These are commercially available from
Elf Atochem (Philadelphia, Pa.) under the tradenames Lotader.TM.
AX8840 (a copolymer of ethylene and 8 wt % glycidyl methacrylate),
Lotader.TM. AX8900 (a terpolymer of ethylene, 25 wt % methyl
acrylate, and 8 wt % glycidyl methacrylate), and Lotader.TM. AX8920
(a terpolymer of ethylene, 26 wt % methyl acrylate, and 1 wt %
glycidyl methacrylate).
[0115] It is also possible to use functional polyolefins which
themselves are blends of the interpolymers of an alpha olefin with
one or more ethylenically unsaturated monomers described and an
additional component comprising a styrenic copolymer. Styrenic
monomers of particular interest for use in preparation of a
styrenic copolymer, in addition to styrene itself, include one or
more of the substituted styrenes or vinyl aromatic compounds
described by the following formula [it being understood that a
reference to "styrene" as a comonomer in component (c) is to be
read as a reference to any of the styrenic or vinyl aromatic
monomers described herein or any others of like kind]: wherein each
A is independently hydrogen, a C1-C6 alkyl radical or a halogen
atom such as chlorine or bromine; and each E is independently
hydrogen, a C1-C10 alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl,
alkaryl, aralkyl or alkoxy radical, a halogen atom such as chlorine
or bromine, or two E's may be joined to form a naphthalene
structure. Representative examples of suitable styrenic monomers,
in addition to styrene itself, include one or more of the
following: ring-substituted alkyl styrenes, e.g. vinyl toluene,
o-ethylstyrene, p-ethylstyrene, p-(t-butyl)styrene,
2,4-dimethylstyrene; ring-substituted halostyrenes, e.g.,
o-chlorostyrene, p-chlorostyrene, o-bromostyrene,
2,4-dichlorostyrene; ring-alkyl, ring-halo-substituted styrenes,
e.g. 2-chloro-4-methylstyrene and 2,6-dichloro-4-methylstyrene;
ar-methoxy styrene, vinylnaphthalene or anthracene,
p-diisopropenylbenzene, di-vinylbenzene, vinyixylene,
alpha-methylstyrene, and alpha-methylvinyltoluene.
[0116] Ethylenically unsaturated monomers of particular interest
for copolymerization with a styrenic monomer include one or more of
those described by the formula:
D--CH.dbd.C(D)--(CH.sub.2).sub.n--G,
[0117] wherein each D independently represents a substituent
selected from the group consisting of hydrogen, halogen (such as
fluorine, chlorine or bromine), C1-C6 alkyl or alkoxy, or taken
together represent an anhydride linkage; G is hydrogen, vinyl,
C1-C12 alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkaryl,
arylalkyl, alkoxy, aryloxy, ketoxy, halogen (such as fluorine,
chlorine or bromine), cyano or pyridyl; and n is 0-9.
[0118] Representative examples of ethylenically unsaturated
monomers copolymerizable with a styrenic monomer are those which
bear a polar or electronegative group and include one or more of
the following: a vinyl nitrile compound such as acrylonitrile,
methacrylonitrile, ethacrylonitrile, alphachloroacrylonitrile and
fumaronitrile; a diene such as butadiene, isoprene, isobutylene,
piperylene, cyclopentadiene, natural rubber, chlorinated rubber,
1,2-hexadiene, methyl-1,3-pentadiene,
2,3-dimethyl-1,3-1,3-pentadiene, 2-methyl-3-ethyl-1,3-butadiene,
2-ethyl-1,3-pentadiene, 1,3- and 2,4-hexadienes, chloro- and bromo
substituted butadienes such as dichlorobutadiene, bromobutadiene,
chloroprene and dibromobutadiene, and butadiene/isoprene and
isoprene/isobutylene copolymers; 1,3-divinylbenzene; 2-phenyl
propene; a C2-C10 alkylene compound including halo-substituted
derivatives thereof such as vinyl or vinylidine chloride; the
alpha, beta-ethylenically unsaturated carboxylic acids, such as
acrylic acid, methacrylic acid, maleic acid, succinic acid,
acotinic acid and itaconic acid, and their anhy-drides and C1-C10
alkyl, aminoalkyl and hydroxyalkylesters and amides, such as alkyl
acrylates and methacrylates such as methyl acrylate, propyl
acrylate, butyl acrylate, octyl acrylate, methyl alpha-chloro
acrylate, methyl, ethyl or isobutyl methacrylate, hydroxyethyl and
hydroxypropyl acrylates, aminoethyl acrylate and glycidyl
methacrylate; maleic anhydride; an alkyl or aryl maleate or
fumarate such as diethylchloromaleate or diethyl fumarate; an
aliphatic or aromatic maleimide, such as N-phenyl maleimide,
including the reaction product of a C1-C10 alkyl or C6-C14 aryl
primary amine and maleic an-hydride; methacrylamide, acrylamide or
N.N-diethyl acrylamide; vinyl ketones such as methyl vinyl ketone
or methyl isopropenyl ketone; vinyl or allyl acetate and higher
alkyl or aryl vinyl or allyl esters; vinyl alcohols; vinyl ethers
such as C1-C6 alkyl vinyl ether and their alkyl-substituted halo
derivatives; vinyl pyridines; vinyl furans; vinyl aldehydes such as
acrolein or crotonaldehyde; vinylcarbazole; vinyl pyrrolidone;
N-vinylphthalimide; and anoxazoline compound includes those of the
general formula where each J is independently hydrogen, halogen, a
C1-C10 alkyl radical or a C6-C14 aryl radical; and the like. Also
included are the various anti drip agents including but not limited
to, polyterafluroethylene (PTFE) such as Teflon.TM. (product and
trade mark of Du Pont Chemical).
[0119] Examples of preferred styrenic copolymers are vinyl
aromatic/vinyl nitrile copolymers such as styrene/acrylonitrile
copolymer ("SAiN"), styrene/maleic anhydride copolymer,
styrene/glycidyl methacrylate copolymer, arylmaleimimde/vinyl
nitrile/diene/styrenic copolymer, styrene/alkyl methacrylate
copolymer, styrene/alkylmethacrylate/glydicyl methacrylate
copolymer, styrene/butyl acrylate copolymer, methyl
methacryalte/acrylonitrile/butadiene/styrene copolymer, or a
rubber-modified vinyl aromatic/vinyl nitrile copolymer such as an
ABS, AES or ASA copolymer. Of these, preferred are the vinyl
aromatic/vinyl nitrile copolymers such as styrene/acrylonitrile
copolymer ("SAN"), styrene/maleic anhydride copolymer,
styrene/glycidyl methacrylate copolymer, and most preferred is the
styrene/acrylonitrile copolymer ("SAN"),
[0120] Additives and Fillers
[0121] A variety of additives may be advantageously employed to
promote flame retardance or ignition resistance in the compositions
of this invention. Representative examples thereof include the
oxides and halides of the metals of Groups IVA and VA of the
periodic table such as the oxides and halides of antimony, bismuth,
arsenic, tin and lead such as antimony oxide, antimony chloride,
antimony oxychloride, stannic oxide, stannic chloride and arsenous
oxide; the organic and inorganic compounds of phosphorous,
nitrogen, boron and sulfur such as aromatic phosphates and
phosphonates (including halogenated derivatives thereof), alkyl
acid phosphates, tributoxyethyl phosphate, 1,3-dichloro-2-propanol
phosphate,
3,9-tribromoneopentoxy-2,4,8,10-tetraoxa-3,9-diphosphaspiro(5.5)undecane--
3,9-dioxide, phosphine oxides, ammonium phosphate, zinc borate,
thiourea, urea, ammonium sulfamate, ammonium polyphos phoric acid
and stannic sulfide; the oxides, halides and hydrates of other
metals such as titanium, vanadium, chromium and magnesium such as
titanium dioxide, chromic bromide, zirconium oxide, ammonium
molybdate and stannous oxide hydrate; antimony compounds such as
antimony phosphate, sodium antimonate, KSb(OH)6, NH4 SbF6 and SbS3;
antimonic esters of inorganic acids, cyclic alkyl antimonite esters
and aryl antimonic acid compounds such as potassium antimony
tartrate, the antimony salt of caproic acid, Sb(OCH.sub.2
CH.sub.3), Sb[OCH(CH.sub.3)CH.sub.2CH.sub.3].sub.3, antimony
polyethylene glycorate, pentaerythritol antimonite and triphenyl
antimony; boric acid; alumina trihydrate; ammonium fluoroborate;
molybdenum oxide; halogenated hydrocarbons such as
hexabromocyclodecane; decabromomdiphenyloxide;
1,2-bis(2,4,6-tribromophenoxy) ethane; halogenated carbonate
oligomers such as those prepared from Tetrabromobisphenol-A;
halogenated epoxy resins such as brominated glycidyl ethers;
tetrabromo phthalic anhydride; fluorinated olefin polymers or
copolymers such as poly(tetrafluoroethylene); octabromodiphenyl
oxide; ammonium bromide; isopropyl di(4-amino benzoyl) isostearoyl
titanate; and metal salts of aromatic sulfur compounds such as
sulfates, bisulfates, sulfonates, sulfonamides and sulfimides;
other alkali metal and alkaline earth metal salts of sulfur,
phosphorus and nitrogen compounds; and others as set forth in
Laughner, U.S. Pat. No.4,786,686, which is incorporated herein; and
the like, and mixtures thereof A preferred flame retardant additive
is antimony trioxide (Sb2O.sub.3). When a flame retardant is used
in the compositions of this invention, it is typically used in an
amount of up to about 15 percent, advantageously from about 0.01
15. to 15 percent, preferably from about 0.1 to 10 percent and more
preferably from about 0.5 to 5 percent, by weight of the total
composition.
[0122] A variety of additives may be advantageously used in the
compositions of this invention for other purposes such as the
following: antimicrobial agents such as organometallics,
isothtazolones, organosulfurs and mercaptans; antioxidants such as
phenolics, secondary amines, phophites and thioesters; antistatic
agents such as quaternary ammonium compounds, amines, and
ethoxylated, propoxylated or glycerol compounds; hydrolytic
stabilizers; lubricants such as fatty acids, fatty alcohols,
esters, fatty amides, metallic stearates, paraffinic and
microcrystalline waxes, silicones and orthophosphoric acid esters;
mold release agents such as fine-particle or powdered solids,
soaps, waxes, silicones, polyglycols and complex esters such as
trimethylolpropane tristearate or pen-taerythritol tetrastearate;
pigments, dyes and colorants; plasticizers such as esters of
dibasic acids (or their anhydrides) with monohydric alcohols such
as o-phthalates, adipates and benzoates; heat stabilizers such as
organotin mercaptides, an octyl ester of thioglycolic acid and a
barium or cadmium carboxyalte; ultraviolet light stabilizers such
as a hindered amine, an o-hydroxy-phenykbenzotriaz- ole; a
2-hydroxy,4-alkoxybenzophenone, a salicylate, a cyanoacrylate, a
nickel chelate and a benzylidene malonate and oxalanilide.
Preferred hindered phenolic antioxidants are Irganox.TM. 1076
antioxidant, available from Ciba-Geigy Corp, Irganox.TM. 1010,
phosphites (e.g., Irgafos.TM. 168). s Additives such as U. V.
stabilizers, cling additives (e.g., polyisobutylene), antiblock
additives, colorants, pigments, fillers, slip agents (e.g
stearamide and/or erucamide) and the like can also be included in
the interpolymers employed in the blends of and/or employed in the
present invention, to the extent that they do not interfere with
the enhanced properties discovered by Applicants.
[0123] Also included as a potential component of the polymer
compositions used in the present invention are various organic and
inorganic fillers, the identity of which depends upon the type of
application in the blend is to be utilized. Representative examples
of such fillers include organic and inorganic fibers such as those
made from asbestos, boron, graphite, ceramic, glass, metals (such
as stainless steel) or polymers (such as aramid fibers) talc,
carbon black, carbon fibers, calcium carbonate, alumina trihydrate,
glass fibers, marble dust, cement dust, clay, feldspar, silica or
glass, fumed silica, alumina, magnesium oxide, magnesium hydroxide,
antimony oxide, zinc oxide, barium sulfate, aluminum silicate,
calcium silicate, titanium dioxide, titanates, aluminum nitride,
B.sub.2O.sub.3, nickel powder or chalk.
[0124] Other representative organic or inorganic, fiber or mineral,
fillers include carbonates such as barium, calcium or magnesium
carbonate; fluorides such as calcium or sodium aluminum fluoride;
hydroxides such as aluminum hydroxide; metals such as aluminum,
bronze, lead or zinc; oxides such as aluminum, antimony, magnesium
or zinc oxide, or silicon or titanium dioxide; silicates such as
asbestos, mica, clay (kaolin or calcined kaolin), calcium silicate,
feldspar, glass (ground or flaked glass or hollow glass spheres or
microspheres or beads, whiskers or filaments), nepheline, perlite,
pyrophyllite, talc or wollastonite; sulfates such as barium or
calcium sulfate; metal sulfides; cellulose, in forms such as wood
or shell flour; calcium terephthalate; and liquid crystals.
Mixtures of more than one such filler may be used as well.
[0125] The additives are employed in functionally equivalent
amounts known to those skilled in the art. For example, the amount
of antioxidant employed is that amount which prevents the polymer
or polymer blend from undergoing oxidation at the temperatures and
environment employed during storage and ultimate use of the
polymers. Such amount of antioxidants is usually in the range of
from 0.01 to 10, preferably from 0.05 to 5, more preferably from
0.1 to 2 percent by weight based upon the weight of the polymer or
polymer blend. Similarly, the amounts of any of the other
enumerated additives are the functionally equivalent amounts such
as the amount to render the polymer or polymer blend antiblocking,
to produce the desired amount of filler loading to produce the
desired result, to provide the desired color from the colorant or
pigment. Such additives can suitably be employed in the range of
from 0. 05 to 50, preferably from 0.1 to 35, more preferably from
0.2 to 20 percent by weight based upon the weight of the polymer or
polymer blend. However, in the instance of fillers, they could be
employed in amounts up to 90 percent by weight based on the weight
of the polymer or polymer blend. Additives such as fillers also
play a role in the aesthetics of a final article providing a gloss
or matte finish.
[0126] The Final Blend Compositions
[0127] The compositions of the present invention are prepared by
any convenient method, including dry blending the individual
components and subsequently melt mixing or melt compounding, either
directly in the extruder or mill used to make the finished article
(e.g., the automotive part), or by pre-melt mixing in a separate
extruder or mill (e.g., a Banbury mixer).
[0128] There are many types of molding operations which can be used
to form useful fabricated articles or parts from the present
compositions, including thermoforming and various injection molding
processes (e.g., that described in Modern Plastics Encyclopedial89,
Mid October 1988 Issue, Volume 65, Number 11, pp. 264-268,
"Introduction to Injection Molding" and on pp. 270-271, "Injection
Molding Thermoplastics", the disclosures of which are incorporated
herein by reference) and blow molding processes (e.g., that
described in Modern Plastics Encyclopedia/89, Mid October 1988
Issue, Volume 65, Number 11, pp. 217-218, "Extrusion-Blow Molding",
the disclosure of which is incorporated herein by reference) and
profile extrusion. Also included are direct blending and final part
formation in a single melt processing operation to fabricate, for
example, sheets and films. Some of the fabricated articles include
sports articles, containers such as for food or other household
articles, footwear, and automotive articles, such as soft facia.
The compositions of the present invention, in combination with the
final part forming operation, can be selected to control part
aesthetics such as a gloss or matte appearance.
[0129] a) Properties of the .alpha.-Olefin/Hindered Vinyl or
Vinylidene Interpolymer and Engineering Thermoplastic Blend
Compositions
[0130] The polymer compositions of the present invention comprise
from about I to 80, preferably from about 1 to 65, more preferably
from about 1 to 50 wt% (based on the 1S combined weights of the
substantially random interpolymer component and the engineering
thermoplastic component) of one or more interpolymers of one or
more .alpha.-olefins and one or more vinyl or vinylidene aromatic
monomers and/or one or more hindered aliphatic or cycloaliphatic
vinyl or vinylidene monomers.
[0131] These substantially random interpolymers usually contain
from about 0.5 to about 50 preferably from about 20 to about 50,
more preferably from about 30 to about 45 mole percent of at least
one vinyl or vinylidene aromatic monomer and/or hindered aliphatic
or cycloaliphatic vinyl or vinylidene monomer and from about 50 to
about 99.5, preferably from about 50 to about 80, more preferably
from about 55 to about 70 mole percent of at least one aliphatic
.alpha.-olefin having from 2 to about 20 carbon atoms.
[0132] The number average molecular weight (Mn) of the
substantially random interpolymer used in the present invention is
greater than about 1000, preferably from about 5,000 to about
1,000,000, more preferably from about 10,000 to about 500,000.
[0133] The melt index (I.sub.2) of the substantially random
interpolymer used in the present invention is from about 0.01 to
about 100, preferably of from about 0.01 to about 10, more
preferably of from about 0.01 to about 5.0 g/10 min.
[0134] The molecular weight distribution (M.sub.w/M.sub.n) of the
substantially random interpolymer used in the present invention is
from about 1.5 to about 20, preferably of from about 1.8 to about
10, more preferably of from about 2 to about 5.
[0135] The compositions of the present invention can also comprise
from 20 to about 99, preferably from 35 to about 99, more
preferably from 50 to about 99 percent of by weight of at least one
engineering thermoplastic (based on the combined weights of the
substantially random interpolymer component and the engineering
thermoplastic component) which can comprise acetal and acrylic
resins, polyamides (e.g. nylon-6, nylon 6,6,), polyimides,
polyetherimides, cellulosics, polyesters, poly(arylate), aromatic
polyesters, poly(carbonate), poly(butylene) and polybutylene and
polyethylene terephthalates, polyethers, polycyclopentanes, and its
copolymers, polymethylpentane, poly(carbonate), polyethylene
terephthalate and polybutylene terephthalate. Of these preferred
are poly(carbonate), polyethylene terephthalate and polybutylene
terephthalate, and most preferred is poly(carbonate).
[0136] The weight average molecular weight (Mw) of the engineering
thermoplastic used to prepare the blends of the present invention
is from about 10,000 to about 40,000, preferably from about 15,000
to about 38,000, more preferably from about 20,000 to about
36,000.
[0137] The melt flow rate of the engineering thermoplastic used to
prepare the blends of the present invention is from about 2 to
about 80, preferably of from about 4 to about 30, more preferably
of from about 6 to about 30 g/10 min.
[0138] b) Properties of the .alpha.-olefin/Hindered Vinal or
Vinylidene Interpolymer/Engineering Thermoplastic/Polyolefin
Elastomer/Functional Polyolefin Blend Compositions
[0139] The polymer compositions of the present invention comprise
from about 1 to 80, preferably from about 1 to 65, more preferably
from about 1 to 50 wt% (based on the combined weights of the
substantially random interpolymer component and the engineering
thermoplastic component) of one or more interpolymers of one or
more .alpha.-olefins and one or more vinyl or vinylidene aromatic
monomers and/or one or more hindered aliphatic or cycloaliphatic
vinyl or vinylidene monomers.
[0140] These substantially random interpolymers usually contain
from about 0.5 to about 50 preferably from about 20 to about 50,
more preferably from about 30 to about 45 mole percent of at least
one vinyl or vinylidene aromatic monomer and/or hindered aliphatic
or cycloaliphatic vinyl or vinylidene monomer and from about 50 to
about 99.5, preferably from about 50 to about 80, more preferably
from about 55 to about 70 mole percent of at least one aliphatic
.alpha.-olefin having from 2 to about 20 carbon atoms.
[0141] The number average molecular weight (Mn) of the
substantially random interpolymer is greater than about 1000,
preferably from about 5,000 to about 1,000,000, more preferably
from about 10,000 to about 500,000.
[0142] The melt index (I.sub.2) of the substantially random
interpolymer used in the present invention is from about 0.01 to
about 100, preferably of from about 0.01 to about 10, more
preferably of from about 0.01 to about 5.0 g/10 min.
[0143] The molecular weight distribution (M.sub.w/M.sub.n) of the
substantially random interpolymer is from about 1.5 to about 20,
preferably of from about 1.8 to about 10, more preferably of from
about 2 to about 5.
[0144] The compositions of the present invention can also comprise
from 20 to about 99, preferably from 35 to about 99, more
preferably from 50 to about 99 percent of by weight of at least one
engineering thermoplastic (based on the combined weights of the
substantially random interpolymer component and the engineering
thermoplastic component) which can comprise acetal and acrylic
resins, polyamides (e.g. nylon-6, nylon 6,6,), polyimides,
polyetherimides, cellulosics, polyesters, poly(arylate), aromatic
polyesters, poly(carbonate), poly(butylene) and polybutylene and
polyethylene terephthalates, polyethers, polycyclopentanes, and its
copolymers, polymethylpentane, poly(carbonate), polyethylene
terephthalate and polybutylene terephthalate. Of these preferred
are poly(carbonate), polyethylene terephthalate and polybutylene
terephthalate, and most preferred is poly(carbonate).
[0145] The weight average molecular weight (Mw) of the engineering
thermoplastic used to prepare the blends of the present invention
is from about 10,000 to about 40,000, preferably from about 15,000
to about 38,000, more preferably from about 20,000 to about
36,000.
[0146] The melt flow rate of the engineering thermoplastic used to
prepare the blends of the present invention is from about 2 to
about 80, preferably of from about 4 to about 30, more preferably
of from about 6 to about 30 g/10 min.
[0147] The polymer compositions of the present invention comprise
from about 15 to 30, preferably from about 10 to 20, more
preferably from about 3 to 15 wt % (based on the combined weights
of the individual blend components) of one or more polyolefin
elastomers.
[0148] The melt index (I.sub.2) of the polyolefin elastomer blend
component is from about 0.01 to about 100, preferably of from about
0.1 to about 10, more preferably of from about 0.25 to about 5.0
g/10 min.
[0149] The density of the polyolefin elastomer blend component is
from about 0.860 to about 0.900, preferably of from about 0.860 to
about 0.895 more preferably of from about 0.860 to about 0.885
g/cm.sup.3.
[0150] The polyolefin elastomer is a homogeneous or heterogeneous
interpolymer comprising between about 50 to 95 weight percent
ethylene and about 5 to 50, and preferably 10 to 25, weight percent
of at least one alph.alpha.-olefin comonomer. The comonomer content
is measured using infrared spectroscopy according to ASTM D-2238,
Method B. Typically, the polyolefin elastomers are copolymers of
ethylene and one or more alph.alpha.-olefins of 3 to about 20
carbon atoms (e.g. propylene, 1-butene, 1-hexene,
4-methyl-1-pentene, 1-heptene, 1-octene and/or styrene), preferably
alpha-olefins of 3 to about 10 carbon atoms, and more preferably
these polymers are a copolymer of ethylene and 1-octene.
[0151] Preferably the polyolefin elastomer is a homogeneous
interpolymer and most preferably is a substantially linear
interpolymer. For substantially linear polyolefin elastomers, the
melt flow ratio, measured as I.sub.10/I.sub.2, is greater than or
equal to 5.63, is preferably from about 6.5 to 15, and is more
preferably from about 7 to 10. Their molecular weight distribution
[weight average molecular weight divided by number average
molecular weight (Mw /Mn)], measured by gel permeation
chromatography (GPC), is defined by the equation: Mw /Mn
<(I.sub.10/I.sub.2)-4.63, and is preferably between about 1.5
and 2.5. For substantially linear ethylene polymers, the I10/I2
ratio indicates the degree of long-chain branching, i.e. the larger
the I10/I2 ratio, the more long-chain branching in the polymer.
[0152] The polymer compositions of the present invention comprise
from about 0.5 to 20, preferably from about 0.5 to 15, more
preferably from about 1 to 10 wt% (based on the combined weights of
the individual blend components) of one or more functional
polyolefins which comprise interpolymers of an alpha olefin with
one or more ethylenically unsaturated monomers.
[0153] Of these, the preferred .alpha.-olefin is ethylene, and the
preferred ethylenically unsaturated monomers are methyl acrylate,
and glycidyl methacrylate. Also preferred are blends of the
.alpha.-olefin/ethylenically unsaturated interpolymer and a
styrenic copolymer. Examples of preferred styrenic copolymers are
vinyl aromatic/vinyl nitrile copolymers such as
styrene/acrylonitrile copolymer ("SAN"), styrene/maleic anhydride
copolymer, styrene/glycidyl methacrylate copolymer,
arylmaleimimde/vinyl nitrile/diene/styrenic copolymer,
styrene/alkyl methacrylate copolymer, styrene/alkylmethacrylat-
e/glydicyl methacrylate copolymer, styrene/butyl acrylate
copolymer, methyl methacryalte/acrylonitrile/butadiene/styrene
copolymer. Of these, preferred are the vinyl aromatic/vinyl nitrile
copolymers such as styrene/acrylonitrile copolymer ("SAN"),
styrene/maleic anhydride copolymer, styrene/glycidyl methacrylate
copolymer, and most preferred is the styrene/acrylonitrile
copolymer ("SAN").
[0154] The following examples are illustrative of the invention,
but are not to be construed as to limiting the scope thereof in any
manner.
EXAMPLES
[0155] Test Methods
[0156] a) Melt Flow Measurements
[0157] The molecular weight of the substantially random
interpolymer compositions and the ethylene/.alpha.-olefin
copolymers for use in the present invention is conveniently
indicated using a melt index measurement according to ASTM D-1238,
(Condition 190.degree. C/2.16 kg, formally known as "Condition (E)"
and also known and abbreviated as I.sub.2) was determined. Melt
index is inversely proportional to the molecular weight of the
polymer. Thus, the higher the molecular weight, the lower the melt
index, although the relationship is not linear.
[0158] The molecular weight of the engineering thermoplastic
polycarbonate components used in the present invention are
conveniently indicated using a melt index measurement according to
ASTM Designation D 1238-89, (Condition 300/1.2) also known and
abbreviated as (MFR).
[0159] b) Styrene Analyses
[0160] Interpolymer styrene content and atactic polystyrene
concentration were determined using proton nuclear magnetic
resonance (.sup.1H N.M.R). All proton NMR samples were prepared in
1,1,2,2-tetrachloroethane-d.sub.2 (TCE-d.sub.2). The resulting
solutions were 1.6-3.2 percent polymer by weight. Melt index
(I.sub.2) was used as a guide for determining sample concentration.
Thus when the I.sub.2 was greater than 2 g/10 min, 40 mg of
interpolymer was used; with an I.sub.2 between 1.5 and 2 g/10 min,
30 mg of interpolymer was used; and when the I.sub.2 was less than
1.5 g/10 min, 20 mg of interpolymer was used. The interpolymers
were weighed directly into 5 mm sample tubes. A 0.75 mL aliquot of
TCE-d.sub.2 was added by syringe and the tube was capped with a
tight-fitting polyethylene cap. The samples were heated in a water
bath at 85.degree. C. to soften the interpolymer. To provide
mixing, the capped samples were occasionally brought to reflux
using a heat gun.
[0161] Proton NMR spectra were accumulated on a Varian VXR 300 with
the sample probe at 80.degree. C., and referenced to the residual
protons of TCE-d.sub.2 at 5.99 ppm. The delay times were varied
between 1 second, and data was collected in triplicate on each
sample. The following instrumental conditions were used for
analysis of the interpolymer samples:
[0162] Varian VXR-300, standard .sup.1H:
[0163] Sweep Width, 5000 Hz
[0164] Acquisition Time, 3.002 sec
[0165] Pulse Width, 8 .mu.sec
[0166] Frequency, 300 MHz
[0167] Delay, 1 sec
[0168] Transients, 16
[0169] The total analysis time per sample was about 10 minutes.
[0170] Initially, a .sup.1H NMR spectrum for a sample of the
polystyrene, Styron.TM. 680 (available form the Dow Chemical
Company, Midland, Mich.) was acquired with a delay time of one
second. The protons were "labeled": b, branch; a, alpha; o, ortho;
m, meta; p, para, as shown in FIG. 1 +L. 7
[0171] Integrals were measured around the protons labeled in FIG. 1
+L; the `A` designates aPS. Integral A.sub.7.1 (aromatic, around
7.1 ppm) is believed to be the three ortho/para protons; and
integral A.sub.6.6 (aromatic, around 6.6 ppm) the two meta protons.
The two aliphatic protons labeled .alpha. resonate at 1.5 ppm; and
the single proton labeled b is at 1.9 ppm. The aliphatic region was
integrated from about 0.8 to 2.5 ppm and is referred to as
A.sub.a1. The theoretical ratio for A.sub.71: A.sub.6.6: A.sub.a1
is 3: 2: 3, or 1.5: 1: 1.5, and correlated very well with the
observed ratios for the Styron.TM. 680 sample for several delay
times of 1 second. The ratio calculations used to check the
integration and verify s peak assignments were performed by
dividing the appropriate integral by the integral A.sub.6.6 Ratio
A.sub.r is A.sub.7.1/A.sub.6.6.
[0172] Region A.sub.6.6 was assigned the value of 1. Ratio A1 is
integral A.sub.a1/A.sub.6.6. All spectra collected have the
expected 1.5:1:1.5 integration ratio of (o+p): m: (a+b). The ratio
of aromatic to aliphatic protons is 5 to 3. An aliphatic ratio of 2
to 1 is predicted based on the protons labeled .alpha. and b
respectively in FIG. 1 +L. This ratio was also observed when the
two aliphatic peaks were integrated separately.
[0173] For the ethylene/styrene interpolymers, the .sup.1H NMR
spectra using a delay time of one second, had integrals C.sub.7.1,
C.sub.6.6, and C.sub.a1 defined, such that the integration of the
peak at 7.1 ppm included all the aromatic protons of the copolymer
as well as the o &p protons of aPS. Likewise, integration of
the aliphatic region C.sub.a1 in the spectrum of the interpolymers
included aliphatic protons from both the aPS and the interpolymer
with no clear baseline resolved signal from either polymer. The
integral of the peak at 6.6 ppm C.sub.6.6 is resolved from the
other aromatic signals and it is believed to be due solely to the
aPS homopolymer (probably the meta protons). (The peak assignment
for atactic polystyrene at 6.6 ppm (integral A.sub.6.6) was made
based upon comparison to the authentic sample Styron.TM. 680.) This
is a reasonable assumption since, at very low levels of atactic
polystyrene, only a very weak signal is observed here. Therefore,
the phenyl protons of the copolymer must not contribute to this
signal. With this assumption, integral A6.6 becomes the basis for
quantitatively determining the aPS content.
[0174] The following equations were then used to determine the
degree of styrene incorporation in the ethylene/styrene
interpolymer samples:
[0175] (C Phenyl)=C.sub.7.1+A.sub.7.1-(1.5.times.A.sub.6.6)
[0176] (C Aliphatic)=C.sub.a1-(15.times.A.sub.6.6)
[0177] s.sub.c=(C Phenyl)/5
[0178] e.sub.c=(C Aliphatic-(3.times.s.sub.c))/4
[0179] E=e.sub.c/(e.sub.c+s.sub.c)
[0180] S.sub.c=s.sub.c/(e.sub.c+s.sub.c)
[0181] and the following equations were used to calculate the mol %
ethylene and styrene in the interpolymers. 1 Wt % E = E * 28 ( E *
28 ) + ( S c * 104 ) ( 100 ) and Wt % S = S c * 104 ( E * 28 ) + (
S c * 104 ) ( 100 )
[0182] where: s.sub.c and e.sub.c are styrene and ethylene proton
fractions in the interpolymer, respectively, and S.sub.c and E are
mole fractions of styrene monomer and ethylene monomer in the
interpolymer, respectively.
[0183] The weight percent of aPS in the interpolymers was then
determined by the following equation: 2 Wt % aPS = ( Wt % S ) * ( A
6.6 / 2 S c ) 100 + [ ( Wt % S ) * ( A 6.6 / 2 S c ) ] * 100
[0184] The total styrene content was also determined by
quantitative Fourier Transform Infrared spectroscopy (FTIR).
[0185] c) Deflection Temperature Under Load (D.T.U.L.):
[0186] Deflection temperature under load ("D.T.U.L.") is measured
in accordance with ASTM Designation D 648-82 at 66 psi.
[0187] d) Differential Scanning Calorimetry (DSC):
[0188] A DuPont DSC-2210 was used to measure the thermal transition
temperatures and heat of transition for the samples. In order to
eliminate previous thermal history, samples were first heated to
about 160.degree. C. Heating and cooling curves were recorded at
10.degree. C. /min. Melting (tm from second heat) and
crystallization (tc) temperatures were recorded from the peak
temperatures of the endotherm and exotherm, respectively.
[0189] e) Impact Resistance Impact resistance is measured by the
Izod test ("Izod") according to ASTM Designation D 256-84 (Method
A) at -29.degree. C. and 25.degree. C. The notch is 10 mils (0.254
mm) in radius. Impact is perpendicular to the flow lines in the
plaque from which the bar is cut. Izod results are reported in
ft-lb/in.
[0190] f) Color
[0191] Samples were quantified in terms of colorability using ASTM
standard, E1331-96, (Standard Test Method for Reflectance Factor
and Color by Spectrophotometry Using Hemispherical Geometry). The
spectral reflectance vs wavelength data was obtained with a Hunter
Associates Labaratory ColorQUEST.TM. II colorimeter. The L*, a*,
and b* parameters were determined (with the specular component of
the reflected data included) using the Commission Internationale de
l'Eclairage (CIE) lab scale color scheme using the method as
referenced in standard E308-96, (Standard Practice for Computing
the Colors of Objects by Using the CIE System), also described in
US Pharmacopeia, USP 1995, Ed 23, General Chapter 1061. Under this
scheme the closer the L value to 100, the closer the lightness of
the sample to perfect whiteness. Similarly, the more negative the
a* value, the greener the sample, the more positive the redder the
sample, and the more negative the b* value the bluer the sample,
the more positive the b* value, the more yellow the sample.
[0192] The Individual Blend Components
[0193] ESI #1
[0194] ESI #1 was a substantially random ethylene styrene
interpolymer which had a styrene content of 37.1 wt % (13.7 mol %)
and was prepared using the following cocatalyst and polymerization
method. The actual polymerization conditions are summarized in
Table 1.
[0195] Bis(hydrogenated-tallowalkyl)methylamine Cocatalyst
Preparation.
[0196] Methylcyclohexane (1200 mL) was placed in a 2L cylindrical
flask. While stirring, bis(hydrogenated-tallowalkyl)methylamine
(ARMEEN.RTM. M2HT, 104 g, ground to a granular form) was added to
the flask and stirred until completely dissolved. Aqueous HCl (1M,
200 mL) was added to the flask, and the mixture was stirred for 30
minutes. A white precipitate formed immediately. At the end of this
time, LiB(C.sub.6F.sub.5).sub.4.Et.sub.2O.3 LiCi (Mw =887.3; 177.4
g) was added to the flask. The solution began to turn milky white.
The flask was equipped with a 6" Vigreux column topped with a
distillation apparatus and the mixture was heated (140.degree. C.
external wall temperature). A mixture of ether and
methylcyclohexane was distilled from the flask. The two-phase
solution was now only slightly hazy. The mixture was allowed to
cool to room temperature, and the contents were placed in a 4 L
separatory funnel. The aqueous layer was removed and discarded, and
the organic layer was washed twice with H.sub.2O and the aqueous
layers again discarded. The H.sub.2O saturated methylcyclohexane
solutions were measured to contain 0.48 wt percent diethyl ether
(Et.sub.2O). The solution (600 mL) was transferred into a 1 L
flask, sparged thoroughly with nitrogen, and transferred into the
drybox. The solution was passed through a column (1" diameter, 6"
height) containing 13.times. molecular sieves. This reduced the
level of Et.sub.2O from 0.48 wt percent to 0.28 wt percent. The
material was then stirred over fresh 13.times. sieves (20 g) for
four hours. The Et.sub.2O level was then measured to be 0.19 wt
percent. The mixture was then stirred overnight, resulting in a
further reduction in Et.sub.2O level to approximately 40 ppm. The
mixture was filtered using a funnel equipped with a glass frit
having a pore size of 10-15 .mu.m to give a clear solution (the
molecular sieves were rinsed with additional dry
methylcyclohexane). The concentration was measured by gravimetric
analysis yielding a value of 16.7 wt percent.
[0197] Polymerization
[0198] The various ESI samples were prepared in a 6 gallon (22.7
L), oil jacketed, Autoclave continuously stirred tank reactor
(CSTR). A magnetically coupled agitator with Lightning A-320
impellers provided the mixing. The reactor ran liquid full at 475
psig (3,275 kPa). Process flow was in at the bottom and out of the
top. A heat transfer oil was circulated through the jacket of the
reactor to remove some of the heat of reaction. At the exit of the
reactor was a micromotion flow meter that measured flow and
solution density. All lines on the exit of the reactor were traced
with 50 psi (344.7 kPa) steam and insulated.
[0199] Ethylbenzene solvent was supplied to the reactor at 30 psig
(207 kPa). The feed to the reactor was measured by a Micro-Motion
mass flow meter. A variable speed diaphragm pump controlled the
feed rate. At the discharge of the solvent pump, a side stream was
taken to provide flush flows for the catalyst injection line (1
lb/hr (0.45 kg/hr)) and the reactor agitator (0.75 lb/hr (0.34 kg/
hr)). These flows were measured by differential pressure flow
meters and controlled by manual adjustment of micro-flow needle
valves. Uninhibited styrene monomer was supplied to the reactor at
30 psig (207 kpa). The feed to the reactor was measured by a
Micro-Motion mass flow meter. A variable speed diaphragm pump
controlled the feed rate. The styrene streams was mixed with the
remaining solvent stream. Ethylene was supplied to the reactor at
600 psig (4,137 kPa). The ethylene stream was measured by a
Micro-Motion mass flow meter just prior to the Research valve
controlling flow. A Brooks flow meter/controller was used to
deliver hydrogen into the ethylene stream at the outlet of the
ethylene control valve. The ethylene/hydrogen mixture combines with
the solvent/styrene stream at ambient temperature. The temperature
of the solvent/monomer as it enters the reactor was dropped to
.about.5.degree. C. by an exchanger with -5.degree. C. glycol on
the jacket. This stream entered the bottom of the reactor. The
three component catalyst system and its solvent flush also entered
the reactor at the bottom but through a different port than the
monomer stream. Preparation of the catalyst components took place
in an inert atmosphere glove box. The diluted components were put
in nitrogen padded cylinders and charged to the catalyst run tanks
in the process area. From these run tanks the catalyst was
pressured up with piston pumps and the flow was measured with
Micro-Motion mass flow meters. These streams combine with each
other and the catalyst flush solvent just prior to entry through a
single injection line into the reactor.
[0200] Polymerization was stopped with the addition of catalyst
kill (water mixed with solvent) into the reactor product line after
the micromotion flow meter measuring the solution density. Other
polymer additives can be added with the catalyst kill. A static
mixer in the line provided dispersion of the catalyst kill and
additives in the reactor effluent stream. This stream next entered
post reactor heaters that provide additional energy for the solvent
removal flash. This flash occurred as the effluent exited the post
reactor heater and the pressure was dropped from 475 psig (3,275
kPa) down to .about.250mm of pressure absolute at the reactor
pressure control valve. This flashed polymer entered a hot oil
jacketed devolatilizer. Approximately 85 percent of the volatiles
were removed from the polymer in the devolatilizer. The volatiles
exited the top of the devolatilizer. The stream was condensed with
a glycol jacketed exchanger and entered the suction of a vacuum
pump and was discharged to a glycol jacket solvent and
styrene/ethylene separation vessel. Solvent and styrene were
removed from the bottom of the vessel and ethylene from the top.
The ethylene stream was measured with a Micro-Motion mass flow
meter and analyzed for composition. The measurement of vented
ethylene plus a calculation of the dissolved gasses in the
solvent/styrene stream were used to calculate the ethylene
conversion. The polymer seperated in the devolatilizer was pumped
out with a gear pump to a ZSK-30 devolatilizing vacuum extruder.
The dry polymer exits the extruder as a single strand. This strand
was cooled as it was pulled through a water bath. The excess water
was blown from the strand with air and the strand was chopped into
pellets with a strand chopper.
[0201] ESI #2
[0202] ESI #2 was a substantially random ethylene styrene
interpolymer which had a styrene content of 54.3 wt % (24.2 mol %)
and was prepared as for ESI #1 using the polymerization conditions
summarized in Table 1 and having the properties summarized in Table
2.
[0203] ESI #3
[0204] ESI # 3 was a substantially random ethylene styrene
interpolymer which had a styrene content of 68.2 wt % (36.6 mol %)
and was prepared as for ESI #1 using the polymerization conditions
summarized in Table 1.
1TABLE 1 Polymerization Conditions for ESI Samples 1-3 Reactor
Solvent Ethylene Hydrogen Styrene Temp Flow Flow Flow Flow %
MMAO.sup.c/Ti Sample # C. lb/hr lb/hr sccm lb/hr Conversion
Catalyst Co-Catalyst B/Ti Ratio Ratio ESI#1 90.6 23.37 2.01 0 14.0
85.7 A.sup.a B.sup.b 1.26 6 ESI#2 73.6 15.02 1.30 0 9.7 88.3
A.sup.a B.sup.b 1.24 6 ESI#3 73.4 13.2 1.22 8 12.0 87.4 A.sup.a
B.sup.b 1.24 10 .sup.aCatalyst A is
(t-butylamido)dimethyl(tetramethylcyclopentadienyl)silane-titanium(II)
1,3-pentadiene prepared as described in U.S. Pat. No. 5,556,928,
Example 17 .sup.bCocatalyst B is bis-hydrogenated tallowalkyl
methylammonium tetrakis (pentafluorophenyl)borate. .sup.ca modified
methylaluminoxane commercially available from Akzo Nobel as MMAO-3A
.sup.dSCCM is standard cm.sup.3/min
[0205]
2TABLE 2 Properties of ESI Samples 1-3 ESI ESI Atactic Melt ESI
Styrene Styrene Polystyrene Index, I.sub.2 # (wt %) (mol %) (wt %)
(g/10 m) ESI #1 37.1 13.7 12.4 0.66 ESI #2 54.3 24.2 13.0 0.60 ESI
#3 68.2 36.6 10.1 0.89
[0206] PC #1
[0207] PC #1 was a polycarbonate having a 14 melt flow rate
obtained from and having the registered trademark
Calibre.TM.-300-14 of the supplier, the Dow Chemical Company,
Midland Mich.
[0208] PC #2
[0209] PC #2 was a polycarbonate having a 10 melt flow rate
obtained from and having the registered trademark
Calibre.TM.-300-10 of the supplier, the Dow Chemical Company,
Midland Mich..
[0210] ENGAGE.TM.8180
[0211] ENGAGE.TM. 8180 POE was a substantially linear
ethylene/octene interpolymer having a melt index, I.sub.2, of 0.50
g/10 min, and a density of 0.863 g/cm.sup.3, obtained from, and
having the registered trademark of, the supplier, Dupont Dow
Elastomers.
[0212] PET #1
[0213] PET # I was a polyethylene terephthalate having an intrinsic
viscosity of 0.77 dl/g obtained from and having the registered
trademark Lieghter.TM. of the supplier, Inca International, Milan,
Italy.
[0214] Preparation of the Blends
Example 1
[0215] Example 1 was a 2000 g blend sample containing 95% by weight
of of PC # I having a 14 melt flow rate and 5 wt % of ESI #1 which
had a styrene content of 37.1 wt % (13.7 mol %). The individual
components were tumble blended for 5 minutes and the dry blended
material was then extruded into pellets on a 30 mm Werner
Pfleiderer extruder at 280.degree. C. barrel temperature. The
extruded pellets were dried in an air draft oven at 100.degree. C.
for at least 3 hours. The dried pellets were injection molded on a
70 ton Arburg molding machine at 300.degree. C. into test bars for
further testing and analysis.
Example 2
[0216] Example 2 is a blend containing 95% by weight of PC # I
having a 14 melt flow rate and 5 wt % of ESI # 3 which had a
styrene content of 68.2 wt % (36.6 mol %). The blend was prepared
essentially as for Example 1.
Example 3
[0217] Example 3 is a blend containing 95% by weight of PC # 1
having a 14 melt flow rate and 5 wt % of ESI #2 which had a styrene
content of 54.3 wt % (24.2 mol %). The blend was prepared
essentially as for Example 1.
[0218] Comparative Experiment 1
[0219] Comparative Experiment 1 is a blend containing 95% by weight
of PC # 1 having a 14 melt flow rate and 5 wt % of ENGAGE.TM. 8180
having a melt index, I.sub.2, of 0.50 g/10 min, and a density of
0.863 g/cm.sup.3. The blend was prepared essentially as for Example
1.
[0220] The results of testing of these samples are summarized in
Table 3.
3TABLE 3 ESI # PC # Engage .TM. Izod Izod Example (wt % in (wt % in
8180 (25.degree. C.) (-29.degree. C.) DTUL C # blend) blend) (wt %
in blend) (ft-lb/in) (ft-lb/in) (264 psi) Color Optics 1 ESI 1 PC 1
N/A 11.8 3.0 143 Good Opaque (5%) (95%) 2 ESI 3 PC 1 N/A 12.2 4.0
144 Good Translucent (5%) (95%) 3 ESI 2 PC 1 N/A 11.6 3.0 142 Good
Opaque (5%) (95%) Comp Ex N/A PC 1 ENGAGE 8180 12.1 2.5 141 Poor
Opaque 1 (95%) (5%)
[0221] Analysis of the data in Table 3 indicate that the addition
of the substantially random interpolymer of varying styrene content
produces good colorability whereas the control sample containing
the polyolefin elastomer (Engage.TM. 8180) exhibits poor
colarability. Furthermore Example 2 in which the styrene content of
the substantially random interpolymer is relatively high (68.2 wt
%, 36.6 mol %) displays translucent optical appearance. The
physical and mechanical properties including the low temperature
Izod impact do not show any discernible differences among the
examples and control.
Example 4
[0222] Example 4 is a blend containing 75% by weight of PET # 1
having an intrinsic viscosity of 0.77 dl/g and 25 wt % of ESI # 2
which had a styrene content of 54.3 wt % (24.2 mol %). The blend
was prepared essentially as for Example 1.
[0223] Comparative Experiment 2
[0224] Comparative Experiment 1 is a sample of PET # I having an
intrinsic viscosity of 0.77 dl/g
[0225] The results of Capilliary Rheology testing of these samples
at 27.degree. Care summarized in Table 4.
4TABLE 4 Example 4 Comp. Expt. 2 .gamma..sub.ap .eta..sub.ap
.eta..sub.ap (1/s) (Pa s) (Pa s) 9.999e1 3.6641e1 3.0534e1 2.1496e2
1.7044e1 1.7044e1 4.6403e2 7.8959e0 3.5S32e1 1.0000e3 1.2823e1
3.1742e1 2.1500e3 1.1361e1 2.5846e1 4.6400e3 8.5543e0 2.0399e1
[0226] Analysis of the viscosity versus shear rate data in Table 5
show that a blend of a substantially random ethylene/styrene
interpolymer and polyethylene terephthalate (PET) typically results
in a lower values of .eta..sub.ap for the same .gamma..sub.ap and
hence an improvement in processability over the PET alone.
Example 5
[0227] Example 5 is a blend containing 88% by weight of PC #2
having a 10 g/10 min melt flow rate, 5 wt % of ESI #3 which had a
styrene content of 68.2 wt % (36.6 mol %), 5 wt % of ENGAGE.TM.
8180 having a melt index, I.sub.2, of 0.50 g/10 min, and a density
of 0.863 g/cm.sup.3, and 2 wt % of a blend of 75 wt % of an
ethylene/methyl acrylate/glycidyl methacrylate terpolymer
(Lotader.TM. AX8900) and 25 wt % of a styrene/acrylonitrile (SAN)
copolymer. The blend was prepared essentially as for Example 1.
[0228] Comparative Experiment 3
[0229] Comparative Experiment 3 is a blend containing 93% by weight
of PC # 2 having a 10 g/10 min melt flow rate, 5 wt % of ENGAGE.TM.
8180 having a melt index, I.sub.2, of 0.50 g/10 min, and a density
of 0.863 g/cm.sup.3, and 2 wt % of a blend of 75 wt % of an
ethylene/methyl acrylate/glycidyl methacrylate terpolymer
(Lotader.TM. AX8900) and 25 wt % of a styrene/acrylonitrile (SAN)
copolymer The blend was prepared essentially as for Example 1.
[0230] Comparative Experiment 4
[0231] Comparative Experiment 4 is a blend containing 90% by weight
of PC # 2 having a 10 g/10 min melt flow rate, 5 wt % of ESI # 3
which had a styrene content of 68.2 wt % (36.6 mol %), and 5 wt %
of ENGAGE.TM. 8180 having a melt index, I.sub.2, of 0.50 g/10 min,
and a density of 0.863 g/cm.sup.3. The blend was prepared
essentially as for Example 1.
[0232] Comparative Experiment 5
[0233] Comparative Experiment 5 is a blend containing 93% by weight
of PC #2 having a 10 g/10 min melt flow rate, 5 wt % of ESI #3
which had a styrene content of 68.2 wt % (36.6 mol %), and 2 wt %
of a blend of 75 wt % of an ethylene/methyl acrylate/glycidyl
methacrylate terpolymer (LotaderTM AX8900) and 25 wt % of a
styrene/acrylonitrile (SAN) copolymer. The blend was prepared
essentially as for Example 1.
[0234] The results of testing of these samples are summarized in
Table 6.
5TABLE 6 PC #2 ESI #3 Engage .TM. 8180 Izod Izod Example (wt % in
(wt % in (wt % in E/MA/GMA/ (25.degree. C.) (-29.degree. C.) DTUL C
# blend) blend) blend) SAN (ft-lb/in) (ft-lb/in) (264 psi) Color Ex
5 88.0% 5% 5% 2% 14.3 13.5 124 Good Comp 93.0% N/A 5 % 2% 12.8 13.4
125 Poor Expt. 3 Comp 90.0% 5% 5% N/A 13.0 4.7 124 Good Expt. 4
Comp 93.0% 5 % N/A 2% 15.3 4.6 125 Good Expt. 5
[0235] Analysis of data in Table 5 show that the four component
blend of a substantially random interpolymer (ESI #3), the
engineering thermoplastic (PC #2) A polyolefin elastomer
(ENGAGE.TM. 8180) and a functional polyolefin (E/MA/GMA/SAN)
results in a composition which has both good colorability and good
low temperature impact performance.
[0236] To test for colarability was to determine how green a sample
would look i.e. how negative the a* value when tumble blended prior
to extrusion with the following green dye ingredients and amounts
(based on the final weight of the polymer blend plus dye
compositions):
[0237] 1) 0.0379 wt % of Miles Yellow (a product of the Miles
Chemical Company, )
[0238] 2) 0.0611 wt % Miles Green (a product of the Miles Chemical
Company, )
[0239] 3) 0.3939 wt % Ceba Brown (a product of the Ceba Geigy
Chemical Company, )
[0240] 4) 0.0071 wt % titanium dioxide.
[0241] For the present invention good colorability is indicative of
an a* value more negative than -10, and bad colarability less
negative than -10.
[0242] The following samples were analyzed for colarability and the
results are summarized in Table 7.
6TABLE 7 PC #1 PC #2 ESI #1 ESI #3 Engage .TM. 8180 E/MA/ Example
(wt % in (wt % in (wt % in (wt % in (wt % in GMA/S # blend) blend)
blend) blend) blend) AN L* a* b* Color Ex 1 95 5 N/A N/A 40.68 -13
67 16.69 Good Ex. 5 88.0% 5% 5% 2% 48.87 -13.71 19.68 Good Comp 95
N/A N/A N/A 5% N/A 49.58 -4.55 25.86 Poor Expt. 1
* * * * *