U.S. patent application number 13/082792 was filed with the patent office on 2011-08-11 for flame retardant polycarbonate compositions.
This patent application is currently assigned to E.I. DU PONT DE NEMOURS AND COMPANY. Invention is credited to Christopher P. Junk, Donald Douglas May.
Application Number | 20110195212 13/082792 |
Document ID | / |
Family ID | 39420658 |
Filed Date | 2011-08-11 |
United States Patent
Application |
20110195212 |
Kind Code |
A1 |
Junk; Christopher P. ; et
al. |
August 11, 2011 |
Flame Retardant Polycarbonate Compositions
Abstract
The present invention relates to novel flame retardant
polycarbonate resin compositions comprising at least one aromatic
polycarbonate resin, at least one anti-drip agent, and at least one
salt as defined herein. The present invention also provides methods
for preparing articles comprising said flame retardant composition,
and articles made therefrom.
Inventors: |
Junk; Christopher P.;
(Wilmington, DE) ; May; Donald Douglas; (Chadds
Ford, PA) |
Assignee: |
E.I. DU PONT DE NEMOURS AND
COMPANY
Wilmington
DE
|
Family ID: |
39420658 |
Appl. No.: |
13/082792 |
Filed: |
April 8, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12038870 |
Feb 28, 2008 |
7947770 |
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13082792 |
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60905555 |
Mar 7, 2007 |
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60958194 |
Jul 3, 2007 |
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Current U.S.
Class: |
428/35.7 ;
264/241; 264/523; 524/106; 524/115; 524/139; 524/145; 524/91 |
Current CPC
Class: |
C08K 5/50 20130101; C08L
69/00 20130101; C08K 5/42 20130101; C08L 27/18 20130101; C08L
2666/04 20130101; C08L 69/00 20130101; Y10T 428/1352 20150115 |
Class at
Publication: |
428/35.7 ;
524/106; 524/115; 524/139; 524/145; 524/91; 264/241; 264/523 |
International
Class: |
B32B 1/02 20060101
B32B001/02; C08K 5/3445 20060101 C08K005/3445; C08K 5/49 20060101
C08K005/49; C08K 5/524 20060101 C08K005/524; C08K 5/521 20060101
C08K005/521; C08K 5/3447 20060101 C08K005/3447; B29C 45/14 20060101
B29C045/14; B29C 49/00 20060101 B29C049/00 |
Claims
1. A flame retardant polycarbonate resin composition comprising:
(A) at least one aromatic polycarbonate resin; (B) at least one
anti-drip agent; and (C) at least one salt having the Formula
M.sup.+Q- wherein M.sup.+ is a cation selected from the group
consisting of the following eleven cations: ##STR00007## wherein
R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are
independently selected from the group consisting of: (a) H; (b)
halogen; (c) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25
straight-chain, branched or cyclic alkane or alkene, optionally
substituted with at least one member selected from the group
consisting of Cl, Br, F, I, OH, NH.sub.2 and SH; (d) --CH.sub.3,
--C.sub.2H.sub.5, or C.sub.3 to C.sub.25 straight-chain, branched
or cyclic alkane or alkene comprising one to three heteroatoms
selected from the group consisting of O, N, Si, and S, and
optionally substituted with at least one member selected from the
group consisting of Cl, Br, F, I, OH, NH.sub.2 and SH; (e) C.sub.6
to C.sub.25 unsubstituted aryl or C.sub.6 to C.sub.25 unsubstituted
heteroaryl having one to three heteroatoms independently selected
from the group consisting of O, N, Si, and S; and (f) C.sub.6 to
C.sub.25 substituted aryl or C.sub.6 to C.sub.25 substituted
heteroaryl having one to three heteroatoms independently selected
from the group consisting of O, N, Si, and S; and wherein said
substituted aryl or substituted heteroaryl has one to three
substituents independently selected from the group consisting of:
(1) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25
straight-chain, branched or cyclic alkane or alkene, optionally
substituted with at least one member selected from the group
consisting of Cl, Br, F, I, OH, NH.sub.2 and SH, (2) OH, (3)
NH.sub.2, and (4) SH; R.sup.7, R.sup.8, R.sup.9, and R.sup.10 are
independently selected from the group consisting of: (g)
--CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25 preferably
straight-chain, branched or cyclic alkane or alkene, optionally
substituted with at least one member selected from the group
consisting of Cl, Br, F, I, OH, NH.sub.2 and SH; (h) --CH.sub.3,
--C.sub.2H.sub.5, or C.sub.3 to C.sub.25 straight-chain, branched
or cyclic alkane or alkene comprising one to three heteroatoms
selected from the group consisting of O, N, Si, and S, and
optionally substituted with at least one member selected from the
group consisting of Cl, Br, F, I, OH, NH.sub.2 and SH; (i) C.sub.6
to C.sub.25 unsubstituted aryl or C.sub.6 to C.sub.25 unsubstituted
heteroaryl having one to three heteroatoms independently selected
from the group consisting of O, N, Si, and S; and (j) C.sub.6 to
C.sub.25 substituted aryl or C.sub.6 to C.sub.25 substituted
heteroaryl having one to three heteroatoms independently selected
from the group consisting of O, N, Si, and S; and wherein said
substituted aryl or substituted heteroaryl has one to three
substituents independently selected from the group consisting of
(1) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25
straight-chain, branched or cyclic alkane or alkene, optionally
substituted with at least one member selected from the group
consisting of Cl, Br, F, I, OH, NH.sub.2 and SH, (2) OH, (3)
NH.sub.2, and (4) SH; and wherein optionally at least two of
R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7,
R.sup.8, R.sup.9, and R.sup.10 can together form a cyclic or
bicyclic alkanyl or alkenyl group; and wherein Q.sup.- is an anion
selected from the group consisting of Formula I and Formula II:
##STR00008## wherein: R.sup.11 is selected from the group
consisting of: (1) halogen; (2) --CH.sub.3, --C.sub.2H.sub.5 or
C.sub.3 to C.sub.15 straight-chain or branched alkane or alkene,
optionally substituted with at least one member selected from the
group consisting of Cl, Br, I, OH, NH.sub.2 and SH; (3)
--OCH.sub.3, --OC.sub.2H.sub.5 or C.sub.3 to C.sub.15
straight-chain or branched alkoxy, optionally substituted with at
least one member selected from the group consisting of Cl, Br, I,
OH, NH.sub.2 and SH; (4) C.sub.1 to C.sub.15 straight-chain or
branched fluoroalkyl, optionally substituted with at least one
member selected from the group consisting of Cl, Br, I, OH,
NH.sub.2 and SH; (5) C.sub.1 to C.sub.15 straight-chain or branched
fluoroalkoxy, optionally substituted with at least one member
selected from the group consisting of Cl, Br, I, OH, NH.sub.2 and
SH; (6) C.sub.1 to C.sub.15 preferably straight-chain or branched
perfluoroalkyl; and (7) C.sub.1 to C.sub.15 straight-chain or
branched perfluoroalkoxy; and ##STR00009## wherein: R.sup.12 is
selected from the group consisting of: (1) halogen; (2) --CH.sub.3,
--C.sub.2H.sub.5 or C.sub.3 to C.sub.15 straight-chain or branched
alkane or alkene, optionally substituted with at least one member
selected from the group consisting of Cl, Br, I, OH, NH.sub.2 and
SH; (3) --OCH.sub.3, --OC.sub.2H.sub.5 or C.sub.3 to C.sub.15
straight-chain or branched alkoxy, optionally substituted with at
least one member selected from the group consisting of Cl, Br, I,
OH, NH.sub.2 and SH; (4) C.sub.1 to C.sub.15 straight-chain or
branched fluoroalkyl, optionally substituted with at least one
member selected from the group consisting of Cl, Br, I, OH,
NH.sub.2 and SH; (5) C.sub.1 to C.sub.15 straight-chain or branched
fluoroalkoxy, optionally substituted with at least one member
selected from the group consisting of Cl, Br, I, OH, NH.sub.2 and
SH; (6) C.sub.1 to C.sub.15 straight-chain or branched
perfluoroalkyl; and (7) C.sub.1 to C.sub.15 straight-chain or
branched perfluoroalkoxy.
2. The composition of claim 1 having about 100 parts of component
(A), about 0.01 to about 5.0 parts of component (B), and about
0.001 to about 2.0 parts of component (C).
3. The composition of claim 2 having about 100 parts of component
(A), and about 0.1 to about 3.0 parts of component (B).
4. The composition of claim 2 having about 100 parts of component
(A), and about 0.01 to about 1.0 parts of component (C).
5. The composition of claim 1, wherein the at least one aromatic
polycarbonate resin is prepared from the reaction of
diphenylcarbonate and 2,2-bis(4-hydroxyphenyl)propane.
6. The composition of claim 1, wherein an anti-drip agent is
poly-tetrafluoroethylene.
7. The composition of claim 1, wherein Q.sup.- is selected from the
group consisting of 1,1,2,2-tetrafluoroethanesulfonate;
2-chloro-1,1,2-trifluoroethanesulfonate;
1,1,2,3,3,3-hexafluoropropanesulfonate;
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate;
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate;
2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoro-2-iodoethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)ethanesulfonate;
N,N-bis(1,1,2,2-tetrafluoroethanesulfonyl)imide; and
N,N-bis(1,1,2,3,3,3-hexafluoropropanesulfonyl)imide.
8. The composition of claim 1, wherein component (C) is selected
from the group consisting of 1-butyl-2,3-dimethylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-butyl-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-ethyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-ethyl-3-methylimidazolium
1,1,2,3,3,3-hexafluoropropanesulfonate, 1-hexyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-dodecyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-hexadecyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate, 1-octadecyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate,
N-(1,1,2,2-tetrafluoroethyl)propylimidazole
1,1,2,2-tetrafluoroethanesulfonate,
N-(1,1,2,2-tetrafluoroethyl)ethylperfluorohexylimidazole
1,1,2,2-tetrafluoroethanesulfonate, 1-butyl-3-methylimidazolium
1,1,2,3,3,3-hexafluoropropanesulfonate, 1-butyl-3-methylimidazolium
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate,
1-butyl-3-methylimidazolium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate,
tetradecyl(tri-n-hexyl)phosphonium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate,
tetradecyl(tri-n-butyl)phosphonium
1,1,2,3,3,3-hexafluoropropanesulfonate,
tetradecyl(tri-n-hexyl)phosphonium
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate,
1-ethyl-3-methylimidazolium
1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)sulfonate,
(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-trioctylphosphonium
1,1,2,2-tetrafluoroethanesulfonate,
1-methyl-3-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)imidazolium
1,1,2,2-tetrafluoroethanesulfonate, and tetra-n-butylphosphonium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate.
9. A composition comprising at least one anti-drip agent and at
least one salt according to claim 1.
10. The composition of claim 1 or claim 9 comprising
poly-tetrafluoroethylene micropowder as said at least one anti-drip
agent.
11. The composition of claim 1 or claim 9 comprising
poly-tetrafluoroethylene dispersion as said at least one anti-drip
agent.
12. The composition of claim 1, further comprising at least one
component selected from the group consisting of (1) at least one
additive selected from the group consisting of antioxidants,
ultraviolet absorbents, light stabilizers, internal lubricants, and
flame retardants or flame retarding aids, mold release agents,
antistatic agents, coloring agents, and combinations thereof; (2)
at least one filler; and (3) combinations thereof.
13. The composition of claim 12, wherein an antioxidant comprises a
hindered phenol, ester of phosphorous acid, ester of phosphoric
acid or amine; an ultraviolet absorbent comprises a benzotriazole
or benzophenone; a light stabilizer comprises a hindered amine; an
internal lubricant comprises an aliphatic carboxylic acid ester,
paraffin, silicone oil or polyethylene wax; a mold release agent
comprises pentaerythritol or glycerol; and a filler is selected
from the group consisting of potassium titanate whisker, mineral
fiber, glass fiber, carbon fiber, metallic fiber, aluminum borate
whisker, silicon nitride whisker, boron fiber, zinc oxide whisker
of tetrapod-shap, talc, clay, mica, pearl mica, aluminum foil,
alumina, glass flake, glass beads, glass balloon, carbon black,
graphite, calcium carbonate, calcium sulfate, calcium silicate,
titanium dioxide, zinc sulfide, zinc oxide, silica, asbestos, and
quartz powder.
14. The composition of claim 12, wherein a filler is present at
about 1 part to about 70 parts by weight.
15. A method for preparing a flame retardant polycarbonate article
comprising: (a) mixing the components of the polycarbonate resin
composition as defined in claim 1 to form a mixed composition; (b)
forming the mixed composition into particles; (c) melt forming the
particles of step (b) into a flame retardant polycarbonate
article.
16. The method of claim 15, wherein the mixing is carried out using
a Banbury mixer, a single-screw extruder, a twin-screw extruder, or
a multi-screw extruder.
17. The method of claim 15, wherein the melt forming is carried out
using injection molding, blow molding, extrusion molding,
compression molding, calender molding, or rotation molding.
18. A flame retardant polycarbonate article comprising a flame
retardant polycarbonate resin composition according to claim 1,
selected from the group consisting of glazing or sheet; an
automotive component; a home appliance; packaging; an electrical,
electronic, or technical component; a medical or health care
related article; and a leisure or safety article.
19. A flame retardant polycarbonate article according to claim 18
selected from the group consisting of a component of a window for
an airplane, a train, a school, a high speed aircraft canopy,
automotive headlamp assembly, automotive interior instrument panel,
automotive bumper, automotive window glazing, a houseware item, a
houseware power tool, a refillable water bottle, a refillable milk
bottle, an electrical connector, telephone network device, outlet
box, computer housing, business machine housing, instrument panel,
membrane switch, insulator, protective goggles, safety glasses,
safety sideshields, eyeglasses, mask, sports helmet, motorcycle
helmet, and a safety helmet for firefighters or construction
workers.
Description
TECHNICAL FIELD
[0001] The present invention relates to novel flame retardant
polycarbonate resin compositions.
BACKGROUND
[0002] Polycarbonate resin possesses excellent mechanical strength,
particularly impact strength, electrical properties and optical
clarity, and is widely utilized in a variety of fields of office
automation machinery, electric and electronic machinery,
automobiles, and architecture, among others. Polymers used in
fields such as office automation machinery and electric and
electronic machinery are required to have high flame retardancy.
Typically, polycarbonate resins are made flame retardant through
incorporation of both a flame retardant and an anti-drip agent to
prevent the dripping of molten resin from a burning polycarbonate
resin.
[0003] U.S. Pat. No. 3,775,367 discloses flame retardant
polycarbonate compositions comprising alkali or tetraalkylammonium
salts of perfluoroalkyl sulfonic acids. U.S. Pat. No. 5,449,710
discloses flame retardant polycarbonate compositions comprising
alkali or alkaline-earth metal salts of perfluoroalkanesulfonic
acids.
[0004] A need nevertheless remains for compounds that can be added
at low levels to polycarbonate resins in order to make them flame
retardant. The present invention provides non-perfluorinated,
sulfonated salts that impart flame retardancy to polycarbonate
resins.
SUMMARY
[0005] One embodiment of this invention relates to a flame
retardant polycarbonate composition comprising:
[0006] (A) at least one aromatic polycarbonate resin;
[0007] (B) at least one anti-drip agent; and
[0008] (C) at least one salt having the Formula M.sup.+Q.sup.-,
wherein M.sup.+ and Q.sup.- are as defined hereinbelow. In one
particular embodiment, the flame retardant polycarbonate
composition comprises about 100 parts of component (A), about 0.01
to about 5.0 parts of component (B), and about 0.001 to about 2.0
parts of component (C). In addition, the flame retardant
polycarbonate composition may optionally also comprise one or more
additives, fillers, or combinations thereof.
[0009] In another embodiment of this invention, an anti-drip agent
may be poly-tetrafluoroethylene. In a further embodiment, an
anti-drip agent is supplied as a mixture or kit comprising
component (C).
[0010] Yet another embodiment of this invention provides a method
for preparing a flame retardant polycarbonate article and articles
made therefrom. The method comprises:
[0011] (a) mixing components (A), (B) and (C) and optional
additives, fillers, and combinations thereof of the polycarbonate
resin composition to form a mixed composition;
[0012] (b) forming the mixed composition into particles;
[0013] (c) melt forming the particles of step (b) into a flame
retardant polycarbonate article.
DETAILED DESCRIPTION
[0014] The present invention relates to flame retardant
polycarbonate resin compositions.
[0015] In one embodiment, the present invention relates to a flame
retardant polycarbonate resin composition comprising the following
components:
[0016] (A) at least one aromatic polycarbonate resin;
[0017] (B) at least one anti-drip agent; and
[0018] (C) at least one salt having the Formula M.sup.+Q.sup.-
wherein M.sup.+ is (1) a cation selected from the group consisting
of lithium, sodium, potassium and cesium or (2) a cation selected
from the group consisting of the following eleven cations:
##STR00001##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are
independently selected from the group consisting of:
[0019] (a) H
[0020] (b) halogen
[0021] (c) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25,
preferably C.sub.3 to C.sub.20, straight-chain, branched or cyclic
alkane or alkene, optionally substituted with at least one member
selected from the group consisting of Cl, Br, F, I, OH, NH.sub.2
and SH;
[0022] (d) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25,
preferably C.sub.3 to C.sub.20, straight-chain, branched or cyclic
alkane or alkene comprising one to three heteroatoms selected from
the group consisting of O, N, Si, and S, and optionally substituted
with at least one member selected from the group consisting of Cl,
Br, F, I, OH, NH.sub.2 and SH;
[0023] (e) C.sub.6 to C.sub.25 unsubstituted aryl or C.sub.6 to
C.sub.25 unsubstituted heteroaryl having one to three heteroatoms
independently selected from the group consisting of O, N, Si, and
S; and
[0024] (f) C.sub.6 to C.sub.25 substituted aryl or C.sub.6 to
C.sub.25 substituted heteroaryl having one to three heteroatoms
independently selected from the group consisting of O, N, Si, and
S; and wherein said substituted aryl or substituted heteroaryl has
one to three substituents independently selected from the group
consisting of: [0025] (1) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3
to C.sub.25, preferably C.sub.3 to C.sub.20, straight-chain,
branched or cyclic alkane or alkene, optionally substituted with at
least one member selected from the group consisting of Cl, Br, F,
I, OH, NH.sub.2 and SH, [0026] (2) OH, [0027] (3) NH.sub.2, and
[0028] (4) SH; R.sup.7, R.sup.8, R.sup.9, and R.sup.10 are
independently selected from the group consisting of:
[0029] (g) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25,
preferably C.sub.3 to C.sub.20, straight-chain, branched or cyclic
alkane or alkene, optionally substituted with at least one member
selected from the group consisting of Cl, Br, F, I, OH, NH.sub.2
and SH;
[0030] (h) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3 to C.sub.25,
preferably C.sub.3 to C.sub.20, straight-chain, branched or cyclic
alkane or alkene comprising one to three heteroatoms selected from
the group consisting of O, N, Si, and S, and optionally substituted
with at least one member selected from the group consisting of Cl,
Br, F, I, OH, NH.sub.2 and SH;
[0031] (i) C.sub.6 to C.sub.25 unsubstituted aryl or C.sub.6 to
C.sub.25 unsubstituted heteroaryl having one to three heteroatoms
independently selected from the group consisting of O, N, Si, and
S; and
[0032] (j) C.sub.6 to C.sub.25 substituted aryl or C.sub.6 to
C.sub.25 substituted heteroaryl having one to three heteroatoms
independently selected from the group consisting of O, N, Si, and
S; and wherein said substituted aryl or substituted heteroaryl has
one to three substituents independently selected from the group
consisting of [0033] (1) --CH.sub.3, --C.sub.2H.sub.5, or C.sub.3
to C.sub.25, preferably C.sub.3 to C.sub.20, straight-chain,
branched or cyclic alkane or alkene, optionally substituted with at
least one member selected from the group consisting of Cl, Br, F,
I, OH, NH.sub.2 and SH, [0034] (2) OH, [0035] (3) NH.sub.2, and
[0036] (4) SH; and wherein optionally at least two of R.sup.1,
R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8,
R.sup.9, and R.sup.10 can together form a cyclic or bicyclic
alkanyl or alkenyl group;
[0037] and wherein Q.sup.- is an anion selected from the group
consisting of Formula I and Formula II:
##STR00002##
wherein: R.sup.11 is selected from the group consisting of:
[0038] (1) halogen;
[0039] (2) --CH.sub.3, --C.sub.2H.sub.5 or C.sub.3 to C.sub.15,
preferably C.sub.3 to C.sub.6, straight-chain or branched alkane or
alkene, optionally substituted with at least one member selected
from the group consisting of Cl, Br, I, OH, NH.sub.2 and SH;
[0040] (3) --OCH.sub.3, --OC.sub.2H.sub.5 or C.sub.3 to C.sub.15,
preferably C.sub.3 to C.sub.6, straight-chain or branched alkoxy,
optionally substituted with at least one member selected from the
group consisting of Cl, Br, I, OH, NH.sub.2 and SH;
[0041] (4) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched fluoroalkyl, optionally substituted with
at least one member selected from the group consisting of Cl, Br,
I, OH, NH.sub.2 and SH;
[0042] (5) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched fluoroalkoxy, optionally substituted
with at least one member selected from the group consisting of Cl,
Br, I, OH, NH.sub.2 and SH;
[0043] (6) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched perfluoroalkyl; and
[0044] (7) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched perfluoroalkoxy;
and
##STR00003##
wherein: R.sup.12 is selected from the group consisting of:
[0045] (1) halogen;
[0046] (2) --CH.sub.3, --C.sub.2H.sub.5 or C.sub.3 to C.sub.16,
preferably C.sub.3 to C.sub.6, straight-chain or branched alkane or
alkene, optionally substituted with at least one member selected
from the group consisting of Cl, Br, I, OH, NH.sub.2 and SH;
[0047] (3) --OCH.sub.3, --OC.sub.2H.sub.5 or C.sub.3 to C.sub.15,
preferably C.sub.3 to C.sub.6, straight-chain or branched alkoxy,
optionally substituted with at least one member selected from the
group consisting of Cl, Br, I, OH, NH.sub.2 and SH;
[0048] (4) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched fluoroalkyl, optionally substituted with
at least one member selected from the group consisting of Cl, Br,
I, OH, NH.sub.2 and SH;
[0049] (5) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched fluoroalkoxy, optionally substituted
with at least one member selected from the group consisting of Cl,
Br, I, OH, NH.sub.2 and SH;
[0050] (6) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched perfluoroalkyl; and
[0051] (7) C.sub.1 to C.sub.15, preferably C.sub.1 to C.sub.6,
straight-chain or branched perfluoroalkoxy.
[0052] According to the present invention, a flame retardant
polycarbonate resin composition is a polycarbonate resin
composition that meets flame retardancy requirements after
compounding of the composition. In the United States, flame
retardancy of the compounded composition may be determined using
test specimens prepared from the compounded composition as
described in test method UL-94 of Underwriter's Laboratories, Inc.
(Northbrook, Ill.). It is preferred that the compounded composition
have a V-0 classification according to UL-94.
[0053] The proportion by weight of components (A), (B), and (C) in
the polycarbonate resin composition is about 100 parts of component
(A), about 0.01 to about 5.0 parts of component (B), and about
0.001 to about 2.0 parts of component (C). In a more specific
embodiment, component (B) is added at about 0.1 to about 3.0 parts,
and in an even more specific embodiment, component (B) is added at
about 0.25 to about 1.0 parts. In another embodiment, component (C)
is added at about 0.01 to about 1.0 parts, and in an even more
specific embodiment, component (C) is added at about 0.1 to about
0.5 parts. Where more than one aromatic polycarbonate resin,
anti-drip agent or salt is used, the values for proportion by
weight represent the combined weight of the individual aromatic
polycarbonate resins, salts, or anti-drip agents. Additional
components, such as fillers or pigments as described below, may be
added to the resin composition. The amount of anti-drip agent,
salt, or other optionally added component, added to component (A)
will depend on a number of factors, such as the cost of the added
components, flame retardancy of products produced from the
polycarbonate resin composition, and mechanical and physical
properties of products produced from the polycarbonate resin
composition, such as impact strength.
[0054] Aromatic polycarbonate resins useful for the present
invention comprise the divalent residue of dihydric phenols bonded
through a carbonate linkage and are represented by the formula:
##STR00004##
wherein Ar is a divalent aromatic group. Ar is preferably a
divalent aromatic group represented by the formula:
--Ar.sup.1--Y--Ar.sup.2-- wherein each of Ar.sup.1 and Ar.sup.2
independently represents a divalent carbocyclic or heterocyclic
aromatic group having from 5 to 30 carbon atoms, and Y represents a
divalent alkane group having from 1 to 30 carbon atoms.
[0055] As used herein, the term "carbocyclic" means having or
relating to or characterized by a ring composed of carbon atoms. As
used herein, the term "heterocyclic" means having or relating to or
characterized by a ring of atoms of more than one kind; especially
a ring of carbon atoms containing at least one atom that is not
carbon. "Heterocyclic aromatic groups" are aromatic groups having
one or more ring nitrogen atoms, oxygen atoms or sulfur atoms.
[0056] Each of divalent aromatic groups Ar.sup.1 and Ar.sup.2 is
either unsubstituted or substituted with at least one substituent
which does not affect the polymerization reaction. Examples of
suitable substituents include a halogen atom, an alkyl group having
from 1 to 10 carbon atoms, an alkoxy group having from 1 to 10
carbon atoms, a phenyl group, a phenoxy group, a vinyl group, a
cyano group, an ester group, an amide group and a nitro group.
[0057] Aromatic polycarbonate resins suitable for this invention,
such as Lexan.RTM. HF1110, are commercially available from
suppliers such as General Electric (Waterford, Mass.), or can be
synthesized by any method known to those skilled in the art. A
general description of polycarbonate preparation, processing and
properties can be found in Brunelle, D. J., "Polycarbonates" in
Kirk-Othmer Encyclopedia of Chemical Technology, (Fifth Edition
(2006), John Wiley & Sons, Inc., Hoboken, N.J., Volume 19,
pages 797-828). Two methods for preparing aromatic polycarbonate
resins are described herein; these methods are meant to be
illustrative of the process for preparing aromatic polycarbonate
resins, and not inclusive of all variations or modifications.
[0058] According to one method, aromatic polycarbonate resin can be
prepared by a melt condensation reaction, as described, for
example, in U.S. Pat. No. 5,717,057, column 1, line 4 through
column 45, line 10, U.S. Pat. No. 5,606,007, column 2, line 63
through column 25, line 23, and U.S. Pat. No. 5,319,066, column 2,
line 5 through column 7, line 22. A suitable polycarbonate useful
for the present invention can be produced by the base-catalyzed
reaction of a diaryl carbonate and a dihydric phenol. A variety of
diaryl carbonates and dihydric phenols are used to create
polycarbonates of varying properties. Non-limiting examples of
diaryl carbonates are diphenylcarbonate (DPC), ditolyl carbonate,
bis(chlorophenyl)carbonate, m-cresyl carbonate, dinapthyl
carbonate, bis(diphenyl)carbonate, diethyl carbonate, dimethyl
carbonate, dibutyl carbonate and dicyclohexyl carbonate,
bis(metriylsalicyl) carbonate. Non-limiting examples of dihydric
phenols are 1,1-bis(4-hydroxyphenyl)methane;
1,1-bis(4-hydroxyphenyl)ethane; 2,2-bis(4-hydroxyphenyl) propane
(hereinafter "bisphenol A" or "BPA"); 2,2-bis(4-hydroxyphenyl)
butane; 2,2-bis(4-hydroxyphenyl)octane; 1,1-bis(4-hydroxyphenyl)
propane; 1,1-bis(4-hydroxyphenyl)n-butane;
bis(4-hydroxyphenyl)phenylmethane;
2,2-bis(4-hydroxy-1-methylphenyl)propane;
1,1-bis(4-hydroxy-t-butylphenyl)propane; bis(hydroxyaryl)alkanes
such as 2,2-bis(4-hydroxy-3-bromophenyl)propane;
1,1-bis(4-hydroxyphenyl)cyclopentane; 4,4'-biphenol; and
bis(hydroxyaryl)cycloalkanes such as
1,1-bis(4-hydroxyphenyl)cyclohexane. A common combination used in
industrial polycarbonate production is DPC and BPA.
[0059] Aromatic polycarbonate resins suitable for the present
invention may also be prepared by a phase interface process. The
phase interface process for polycarbonate synthesis is well known,
and is described, for example, in H. Schnell, Chemistry and Physics
of Polycarbonates, Polymer Reviews, vol. 9, Interscience
Publishers, New York 1964 p. 33 et seq.; Polymer Reviews, vol. 10,
"Condensation Polymers by Interfacial and Solution Methods", Paul
W. Morgan, Interscience Publishers, New York 1965, chap. VIII, p.
325; Dres. U, Grigo, K. Kircher and P. R. Muller "Polycarbonate" in
Becker/Braun, Kunststoff-Handbuch, vol. 3/1, Polycarbonate,
Polyacetale, Polyester, Celluloseester, Carl Hanser Verlag Munich,
Vienna 1992, p. 118-145; and U.S. Pat. No. 5,235,026, column 2,
line 65 through column 8, line 8.
[0060] According to this process, the phosgenation of a disodium
salt of a bisphenol (or of a mixture of various bisphenols) which
has been initially introduced into an aqueous-alkaline solution (or
suspension) is carried out in the presence of an inert organic
solvent or solvent mixture which forms a second phase. The
oligocarbonates formed, which are chiefly present in the organic
phase, are subjected to further condensation with the aid of
suitable catalysts such as but not limited to tertiary and
quaternary amines such as triethyl amine and tetramethylammonium
chloride to give high molecular weight polycarbonates dissolved in
the organic phase. Finally, the organic phase is separated off and
the polycarbonate is isolated therefrom by methods as described in
Morgan (supra).
[0061] Polycarbonates suitable for the present invention also
include polydimethylsiloxane-co-BPA polycarbonates. The synthesis
of these polycarbonates is described in U.S. Pat. No. 3,189,662,
column 1, line 9 through column 6, line 7, and U.S. Pat. No.
3,419,634, column 1, line 24 through column 15, line 22. The
polydimethylsiloxane is present in the polydimethylsiloxane-co-BPA
polycarbonate at about at least 1.0 weight percent based on the
combined weight of the dimethylsiloxane plus the BPA. These
polymers differ from those described above in that they have very
low glass transition temperatures, yet retain excellent thermal
stability and have good weathering properties. Additional methods
of preparation are described in Brunelle, D. J. (supra).
[0062] Polycarbonates suitable for the present invention also
include blends of polycarbonates with one or more polyimides,
polyetherimides, polyamides, polyketones, polyesters, polyphenyl
ethers, polystyrenes, acrylonitrile styrenes, acrylonitrile
butadiene styrenes, polyethylenes, polypropylenes, and poly(methyl
methacrylate).
[0063] Any suitable anti-drip agent component (B) can be used in
the polycarbonate resin composition of the invention. The anti-drip
agents can be supplied, for example, as finely ground powders. A
typical anti-drip agent is micropowder poly-tetrafluoroethylene
(p-TFE) (commercially available from E.I. du Pont de Nemours and
Company, Wilmington Del.). In one embodiment, the at least one
anti-drip agent can be supplied as part of a mixture or kit
comprising the at least one anti-drip agent with the at least one
salt (component (C)). The anti-drip agent can be supplied in the
mixture or kit as a powder or dispersion. For example, p-TFE can be
supplied in a mixture or kit as a micropowder or dispersion with
component (C), wherein component C is a lithium, sodium, potassium
or cesium salt of 1,1,2,2-tetrafluoroethanesulfonate or
1,1,2,3,3,3-hexafluoropropanesulfonate. More specifically,
component C can be potassium 1,1,2,2-tetrafluoroethanesulfonate or
potassium 1,1,2,3,3,3-hexafluoropropanesulfonate.
[0064] In preferred embodiments of the invention, component (C)
comprises an anion (Q.sup.-) selected from the group consisting of
1,1,2,2-tetrafluoroethanesulfonate;
2-chloro-1,1,2-trifluoroethanesulfonate;
1,1,2,3,3,3-hexafluoropropanesulfonate;
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate;
1,1,2-trifluoro-2-(pentafluoroethoxy)ethanesulfonate;
2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoro-2-iodoethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)ethanesulfonate;
N,N-bis(1,1,2,2-tetrafluoroethanesulfonyl)imide; and
N,N-bis(1,1,2,3,3,3-hexafluoropropanesulfonyl)imide.
[0065] Thus, in one embodiment, the at least one salt useful as
component (C) comprises a cation selected from the group consisting
of lithium, sodium, potassium, cesium, pyridinium, pyridazinium,
pyrimidinium, pyrazinium, imidazolium, pyrazolium, thiazolium,
oxazolium, triazolium, phosphonium, and ammonium as defined in all
of the embodiments above; and an anion selected from the group
consisting of 1,1,2,2-tetrafluoroethanesulfonate;
2-chloro-1,1,2-trifluoroethanesulfonate;
1,1,2,3,3,3-hexafluoropropanesulfonate;
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate;
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate;
2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
2-(1,1,2,2-tetrafluoro-2-iodoethoxy)-1,1,2,2-tetrafluoroethanesulfonate;
1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)ethanesulfonate;
N,N-bis(1,1,2,2-tetrafluoroethanesulfonyl)imide; and
N,N-bis(1,1,2,3,3,3-hexafluoropropanesulfonyl)imide.
[0066] In another embodiment, the at least one salt useful as
component (C) is selected from the group consisting of
1-butyl-2,3-dimethylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-butyl-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-ethyl-3-methylimidazolium 1,1,2,3,3,3-hexafluoropropanesulfonate,
1-hexyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-dodecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-hexadecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
1-octadecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate,
N-(1,1,2,2-tetrafluoroethyl)propylimidazole
1,1,2,2-tetrafluoroethanesulfonate,
N-(1,1,2,2-tetrafluoroethyl)ethylperfluorohexylimidazole
1,1,2,2-tetrafluoroethanesulfonate, 1-butyl-3-methylimidazolium
1,1,2,3,3,3-hexafluoropropanesulfonate, 1-butyl-3-methylimidazolium
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate,
1-butyl-3-methylimidazolium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate,
tetradecyl(tri-n-hexyl)phosphonium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate,
tetradecyl(tri-n-butyl)phosphonium
1,1,2,3,3,3-hexafluoropropanesulfonate,
tetradecyl(tri-n-hexyl)phosphonium
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate,
1-ethyl-3-methylimidazolium
1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)sulfonate,
(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-trioctylphosphonium
1,1,2,2-tetrafluoroethanesulfonate,
1-methyl-3-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)imidazolium
1,1,2,2-tetrafluoroethanesulfonate, tetra-n-butylphosphonium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate, potassium
1,1,2,2-tetrafluoroethanesulfonate, potassium
1,1,2,3,3,3-hexafluoropropanesulfonate, and potassium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate.
[0067] Sources of cations (M.sup.+) useful for component (C) are
available commercially, or may be synthesized by methods known to
those skilled in the art. The fluoroalkyl sulfonate anions of
Formula I may be synthesized from perfluorinated terminal olefins
or perfluorinated vinyl ethers generally according to the methods
described in U.S. Patent Application No. 2006/0276670, paragraph 14
through paragraph 65 and U.S. Patent Application No. 2006/0276671,
paragraph 12 through paragraph 88; in one embodiment, potassium
sulfite and bisulfite are used as the buffer, and in another
embodiment, the reaction is carried in the absence of a radical
initiator. Preferred isolation methods include freeze drying or
spray drying to isolate the crude
1,1,2,2-tetrafluoroethanesulfonate and
1,1,2,3,3,3-hexafluoropropanesulfonate products from the aqueous
reaction mixture, using acetone to extract the crude
1,1,2,2-tetrafluoroethanesulfonate and
1,1,2,3,3,3-hexafluoropropanesulfonate salts, and crystallizing
1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate and
1,1,2-trifluoro-2-(pentafluoroethoxy)ethanesulfonate from the
reaction mixture by cooling. The bis(fluoroalkylsulfonyl)imides of
Formula II can be synthesized as described for the synthesis of
bis(perfluoroalkylsulfonyl)imide salt compounds such as
(R.sub.fSO.sub.2).sub.2N(-)M(+) (see U.S. Pat. No. 5,847,616;
DesMarteau, D. and Hu, L. Q. (Inorg. Chem. (1993), 32, 5007-5010);
U.S. Pat. No. 6,252,111; Caporiccio, G. et al. (J. Fluor. Chem.
(2004), 125, 243-252); and U.S. Pat. No. 6,399,821). For example,
1,1,2,2-tetrafluoroethanesulfonic acid is first converted to the
corresponding sulfonyl chloride by reaction with a suitable
chlorinating reagent such as PCl.sub.5 or catechol-PCl.sub.3 as
described in U.S. Pat. No. 2,403,207 and European Patent
Application EP47946. The chlorine can be replaced by fluorine using
potassium fluoride in an organic solvent such as acetonitrile to
produce the sulfonyl fluoride.
##STR00005##
[0068] The sulfonyl fluoride is recovered, and two molecules of the
sulfonyl fluoride can be coupled as described in Lyapkalo, I. M.
(Tetrahedron (2006) 62, 3137-3145) to make the
bis(fluoroalkylsulfonyl)imide. According to this procedure,
ammonium chloride and triethylamine (Et.sub.3N) are used in an
organic solvent such as acetonitrile to convert the sulfonyl
fluoride to the triethylammonium (NHEt.sub.3) salt of the
bis(fluoroalkylsulfonyl)imide. The potassium salt is then obtained
by further treatment with potassium hydroxide in aqueous
methanol.
##STR00006##
[0069] In addition to components (A), (B) and (C), the
polycarbonate resin composition of the present invention may
optionally also comprise one or more additives, fillers, or
combinations thereof, as long as these additional components do not
decrease the thermal stability or photochemical stability to a
level that is undesirable, or decrease the flame retardancy of the
polycarbonate to a level that is undesirable or that no longer
meets flame retardancy requirements. Examples of additives include,
but are not limited to, antioxidants such as hindered phenols,
esters of phosphorous acid, esters of phosphoric acid and amines;
ultraviolet absorbents such as benzotriazoles and benzophenones;
light stabilizers such as hindered amines; internal lubricants such
as aliphatic carboxylic acid esters, paraffin, silicone oil and
polyethylene wax; and flame retardants or flame retarding aids;
mold release agents such as pentaerythritol or glycerol; antistatic
agents; coloring agents; and combinations thereof.
[0070] Aromatic polycarbonate resins can be compounded with at
least one filler as is known in the art. Examples of fillers
include potassium titanate whisker, mineral fiber such as rock
wool, glass fiber, carbon fiber, metallic fiber such as stainless
steel fiber, aluminum borate whisker, silicon nitride whisker,
boron fiber, zinc oxide whisker of tetrapod-shap, talc, clay, mica,
pearl mica, aluminum foil, alumina, glass flake, glass beads, glass
balloon, carbon black, graphite, calcium carbonate, calcium
sulfate, calcium silicate, titanium dioxide, zinc sulfide, zinc
oxide, silica, asbestos, quartz powder, and combinations thereof.
Fillers may be surface treated by physical or chemical methods in
order to improve interfacial bonding and enhance mechanical
properties. Interfacial bonding refers to bonding in which the
surfaces of two bodies in contact with one another are held
together by intermolecular forces. Fillers can be treated, for
example, with silane-based coupling agents, higher fatty acids,
metallic salts of fatty acids, unsaturated organic acids, organic
titanates, resin acids, polyethylene glycols, or
polymethylhydrogensiloxane fluids of the type,
Me.sub.3Si--O--[SiOMe.sub.2].sub.m--[SiOMeH].sub.n--SiMe.sub.3
wherein Me is methyl, m can range from 0-100 and n can range from
1-50. Most preferably m is 0 and n is approximately 50.
[0071] The at least one filler is generally used at about 1 part to
about 70 parts by weight (relative to 100 parts of the at least one
aromatic polycarbonate resin). When more than one filler is used,
the value for proportion by weight represents the combined weight
of the individual fillers. In a more specific embodiment, the at
least one filler is used at about 2 parts to about 40 parts by
weight (relative to 100 parts of the at least one aromatic
polycarbonate resin).
[0072] The present invention also relates to a method for preparing
flame retardant polycarbonate articles. According to the method,
the flame retardant polycarbonate articles can be prepared by a
process comprising:
[0073] (a) mixing components (A), (B) and (C), and optional
additives, fillers and combinations thereof, of the polycarbonate
resin composition as defined above;
[0074] (b) forming the mixed composition into particles;
[0075] (c) melt forming the particles of step (b) into a flame
retardant polycarbonate article.
[0076] More specifically, the components of the polycarbonate resin
composition can be mixed by compounding or kneading the components
of the composition using any processing operation known to those
skilled in the art. See, for example, Brunelle, D. J.,
"Polycarbonates" in Kirk-Othmer Encyclopedia of Chemical
Technology, (Fifth Edition (2006), John Wiley & Sons, Inc.,
Hoboken, N.J., Volume 19, pages 797-828) for a description of
processing of polycarbonates. Compounding or kneading can be
carried out, for example, using a Banbury mixer, a single-screw
extruder, a twin-screw extruder, a multi-screw extruder or the
like. Compounding is typically carried out at a temperature of
about 240 degrees Centigrade to about 300 degrees Centigrade.
Components (B), (C), and optional additives or fillers can be added
together with the at least one aromatic polycarbonate resin.
Alternatively, these components can be added at one or more
downstream points in an extruder, for example. The addition of
components downstream can decrease attrition of solids such as
fillers, and/or improve dispersion, and/or decrease the thermal
history of relatively thermally unstable components, and/or
decrease losses by evaporation of volatile components. After the
components are mixed, they may be formed or cut into pellets or
other particles suitable for feeding to a melt forming machine.
Melt forming can be carried out by the usual methods for
thermoplastics, such as injection molding, blow molding, extrusion
molding, compression molding, calendar molding, rotation molding
and the like to form desired articles.
[0077] It is expected that articles formed comprising the
polycarbonate resin compositions of the present invention would
find utility in many applications where polycarbonate is currently
used. Examples include, but are not limited to, glazing and sheet;
automotive components; appliances, such as houseware items and
power tools; packaging, such as refillable water bottles and
refillable milk bottles; electrical, electronic, and technical
components; medical and health-care related articles; and leisure
and safety articles. Examples of glazing and sheet applications
include, but are not limited to, windows for airplanes, trains, and
schools; and high speed aircraft canopies. Such products may be
laminated, for example, with a soft inner layer. Examples of
automotive components include, but are not limited to, headlamp
assemblies, interior instrument panels, bumpers, and automotive
window glazing. Examples of electrical, electronic, and technical
components include, but are not limited to, electrical connectors,
telephone network devices, outlet boxes, computer and business
machine housings, instrument panels, membrane switches and
insulators. Examples of leisure and safety articles include, but
are not limited to, protective headgear (e.g., sports helmets,
motorcycle helmets, and safety helmets for firefighters and
constructions workers) and protective eyewear (e.g., for goggles,
safety glasses, safety sideshields, eyeglasses, and masks). The
resin compositions are particularly useful for those applications
requiring flame retardant materials, such as office automation
machinery, and electric and electronic machinery.
[0078] Flammability of the polycarbonate resin composition can be
determined using appropriate methods. For example, methods may be
used that are appropriate for the country in which the
polycarbonate will be used. In the United States, flame retardant
polycarbonates of the invention may be required to meet
Underwriter's Laboratory standards, particularly UL-94
(Underwriters Laboratories, Inc., Northbrook, Ill.). UL-94 tests
materials based on their ability to resist combustion on repeated
application of a flame, as well as the resistance of materials to
dripping with subsequent ignition of a combustible source (cotton)
from the resulting drips. Test specimens are mounted in a chamber
and ignited for 10 seconds. If the specimen extinguishes, the
afterflame time is recorded and the specimen is reignited for 10
seconds. Materials are then classified on the basis of the
afterflame time and ignition of the cotton caused by flaming drips.
The most widely accepted classes are V-0, V-1 and V-2. Class V-1
allows for a longer afterflame time than V-0, whereas V-2 has the
same afterflame time as V-1, but allows for cotton ignition. For
the present invention an afterflame time of <10 seconds was used
for V-0 and <30 seconds was used for V-1 and V-2.
[0079] In the following examples, the present invention will be
described in more detail with reference to comparative examples and
examples, which however shall not be construed to limit the
invention thereto.
General Materials and Methods
[0080] The following abbreviations were used:
[0081] Degrees Centigrade is "C" or "degrees C"; gram(s) is "g";
"h" is hour"; relative humidity is "RH"; millimeter is "mm";
nuclear magnetic resonance is "NMR"; and differential scanning
calorimetry is "DSC".
[0082] The syntheses of potassium
1,1,2,3,3,3-hexafluoropropanesulfonate (HFPS-K) and potassium
1,1,2,2-tetrafluoroethanesulfonate (TFES-K) are described in U.S.
Patent Application No. 2006/027661, Examples 2, 4 and 5.
Synthesis of tetra-n-butylphosphonium
1,1,2,3,3,3-hexafluoropropanesulfonate (TBP-HFPS)
[0083] Deionized water (2800 mL) and potassium
1,1,2,3,3,3-hexafluoropropanesulfonate (HFPS-K, 551.2 g) were added
to a 4 L erlenmeyer flask. The contents of the flask were stirred
magnetically at room temperature until the HFPS-K dissolved to
produce a clear colorless solution. To this solution was added a 75
wt. % aqueous solution of tetra-n-butylphosphonium bromide
(Cyphos.RTM. 443W, Cytec Canada Inc., 923.0 g). A large amount of
flaky white precipitate was formed, and this mixture was allowed to
stir for 8 h at room temperature. The white precipitated product
was isolated by suction filtration. The crude product was then
stirred magnetically with 1000 mL of saturated sodium carbonate for
30 min. to remove any acidic impurities. The product was again
isolated by suction filtration. The product was further washed with
3.times.1000 mL portions of deionized water to remove any residual
carbonate. This material was isolated by suction filtration and
then dried in vacuo (70 C, 100 Torr, 18 h) above its melting point
to remove water. The product was allowed to cool and solidify in
the oven under a purge of nitrogen gas. The solid product cake was
removed from the oven and passed through a #14 mesh (1.4 mm) screen
to give a free-flowing solid (893 g, 89% yield).
[0084] .sup.19F NMR (CD.sub.2Cl.sub.2) .delta. -74.9 (m, 3F);
-115.3, -122.8 (ABq, J=264 Hz, 2F); -210.1 (dm, 1F). .sup.1H NMR
(CD.sub.2Cl.sub.2) .delta. 1.0 (t, J=7.3 Hz, 12H); 1.5 (m, 16H);
2.2 (m, 8H); 5.4 (dm, J.sub.FH=54 Hz, 1H).
[0085] % Water by Karl-Fisher titration: 671 ppm.
[0086] Melting point (DSC): 74.degree. C.
[0087] Elemental analysis for C.sub.19H.sub.37F.sub.6O.sub.3PS:
Calculated: % C, 46.5; H, 7.6; N, 0.0.
[0088] Experimental results: % C, 46.9: H, 8.0: N, <0.1.
Synthesis of potassium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TPES-K)
[0089] The synthesis of TFES-K has been described in U.S. Patent
Application No. 2006/0276671. A 1-gallon Hastelloy.RTM. C276
reaction vessel was charged with a solution of potassium sulfite
hydrate (88 g, 0.56 mol), potassium metabisulfite (340 g, 1.53 mol)
and deionized water (2000 ml). The vessel was cooled to 7 degrees
C., evacuated to 0.05 MPa, and purged with nitrogen. The
evacuate/purge cycle was repeated two more times. To the vessel was
then added perfluoro(ethylvinyl ether) (PEVE, 600 g, 2.78 mol), and
it was heated to 125 degrees C. at which time the inside pressure
was 2.31 MPa. The reaction temperature was maintained at 125
degrees C. for 10 hr. The pressure dropped to 0.26 MPa at which
point the vessel was vented and cooled to 25 degrees C. The crude
reaction product was a white crystalline precipitate with a
colorless aqueous layer (pH=7) above it.
[0090] The .sup.19F NMR spectrum of the white solid showed pure
desired product, while the spectrum of the aqueous layer showed a
small but detectable amount of a fluorinated impurity. The desired
isomer is less soluble in water so it precipitated in isomerically
pure form.
[0091] The product slurry was suction filtered through a fritted
glass funnel, and the wet cake was dried in a vacuum oven (60
degrees C., 0.01 MPa) for 48 hr. The product was obtained as
off-white crystals (904 g, 97% yield).
[0092] .sup.19F NMR (D.sub.2O) .delta. -86.5 (s, 3F); -89.2, -91.3
(subsplit ABq, J.sub.FF=147 Hz, 2F);
[0093] -119.3, -121.2 (subsplit ABq, J.sub.FF=258 Hz, 2F); -144.3
(dm, J.sub.FH=53 Hz, 1 F).
[0094] .sup.1H NMR (D.sub.2O) .delta. 6.7 (dm, J.sub.FH=53 Hz,
1H).
[0095] Mp (DSC) 263 degrees C.
[0096] Analytical calculation for C.sub.4HO.sub.4F.sub.8SK: C,
14.3: H, 0.3 Experimental results: C, 14.1; H, 0.3.
[0097] TGA (air): 10% wt. loss @ 359 degrees C., 50% wt. loss @ 367
degrees C.
[0098] TGA (N.sub.2): 10% wt. loss @ 362 degrees C., 50% wt. loss @
374 degrees C.
[0099] A similar process can be used for the synthesis of TFES-Na,
using molar amounts equivalent to that described above for
potassium.
Synthesis of 1-butyl-3-methylimidazolium
1,1,2,2-tetrafluoroethanesulfonate (BMIM-TFES)
[0100] 1-Butyl-3-methylimidazolium chloride (60.0 g) and high
purity dry acetone (>99.5%, 300 ml) were combined in a 1 liter
flask and warmed to reflux with magnetic stirring until the solid
completely dissolved. At room temperature in a separate 1 liter
flask, potassium-1,1,2,2-tetrafluoroethanesulfonte (TFES-K, 75.6 g)
was dissolved in high purity dry acetone (500 ml). These two
solutions were combined at room temperature and allowed to stir
magnetically for 2 hr under positive nitrogen pressure. The
stirring was stopped and the KCl precipitate was allowed to settle,
then removed by suction filtration through a fritted glass funnel
with a celite pad. The acetone was removed in vacuo to give a
yellow oil. The oil was further purified by diluting with high
purity acetone (100 ml) and stirring with decolorizing carbon (5
g). The mixture was again suction filtered and the acetone removed
in vacuo to give a colorless oil. This was further dried at 4 Pa
and 25 degrees C. for 6 hr to provide 83.6 g of product.
[0101] .sup.19F NMR (DMSO-d.sub.6) .delta. -124.7 (dt, J=6 Hz, J=8
Hz, 2F); -136.8 (dt, J=53 Hz, 2F).
[0102] .sup.1H NMR (DMSO-d.sub.6) .delta. 0.9 (t, J=7.4 Hz, 3H);
1.3 (m, 2H); 1.8 (m, 2H); 3.9 (s, 3H); 4.2 (t, J=7 Hz, 2H); 6.3
(dt, J=53 Hz, J=6 Hz, 1H); 7.4 (s, 1H); 7.5 (s, 1H); 8.7 (s,
1H).
[0103] % Water by Karl-Fisher titration: 0.14%.
[0104] Analytical calculation for
C.sub.9H.sub.12F.sub.6N.sub.2O.sub.3S: C, 37.6; H, 4.7; N, 8.8.
[0105] Experimental Results: C, 37.6: H, 4.6: N, 8.7.
[0106] TGA (air): 10% wt. loss @ 380 degrees C., 50% wt. loss @ 420
degrees C.
[0107] TGA (N.sub.2): 10% wt. loss @ 375 degrees C., 50% wt. loss @
422 degrees C.
Synthesis of Lithium and Cesium Salts of Fluorinated
Alkylsulfonates
[0108] Potassium and sodium salts of fluorinated alkylsulfonates,
either purified or as crude dried reaction mixtures, can be
converted into their anhydrous acids as taught in U.S. patent
application 2006/0276671. These acids can then be allowed to react
with lithium or cesium carbonate in an organic solvent such as
methanol to give in high yield the corresponding lithium or cesium
fluorinated alkylsulfonate salt. The lithium or cesium salt product
can be isolated by first removing any excess insoluble carbonate
salt by filtration and then removing the organic solvent by vacuum
distillation. Caution should be taken with the lithium salt to keep
the system anhydrous since lithium salts are typically extremely
hygroscopic.
Synthesis of lithium 1,1,2,2-tetrafluoroethanesulfonte (TFES-Li)
from 1,1,2,2-tetrafluoroethanesulfonic acid (TFESA)
[0109] 1,1,2,2-tetrafluoroethanesulfonic acid (10.05 g, 0.055 mol)
and dry methanol (10 mL; EMD Chemicals Inc., Gibbstown, N.J.) were
added to a 20 mL vial. The solution was cooled to 0 C with magnetic
stirring in an ice bath under an atmosphere of nitrogen. In a
separate flask, lithium carbonate (0.95 g, 0.026 mol; Aldrich, St.
Louis, Mo.) was mixed with dry methanol (10 mL) and stirred
magnetically in an ice bath under an atmosphere of nitrogen until
it too was at 0 C. The TFESA solution was then added slowly to the
carbonate mixture generating a large amount of gaseous CO.sub.2.
Once addition was complete and the evolution of gas stopped, the
methanol was removed in vacuo on a rotary evaporator. The flask was
then heated in vacuo to 80 C for 3 hours to drive off the water
which was formed during the reaction. A white powdery product
(TFES-Li, 8.7 g, 84% yield) was isolated and characterized.
[0110] % water by Karl-Fisher titration: 0.27 wt.
[0111] Elemental analysis for C.sub.2H.sub.1F.sub.4LiO.sub.3S:
Calculated: % C, 12.78; H, 0.54.
[0112] Experimental results: % C, 12.53: H, 0.74.
Synthesis of 1-butyl-3-methylimidazolium nonafluorobutanesulfonate
(BMIM-NONA)
[0113] BMIM-NONA can be synthesized as described in S. K. Quek, et
al. (Tetrahedron (2006) 62:3137-3145.
Synthesis of tetradecyl(tri-n-butyl)phosphonium
1,1,2,2-tetrafluoroethanesulfonate ([4.4.4.14]P-TFES)
[0114] In a 1000 mL flask, potassium
1,1,2,2-tetrafluoroethanesulfonate (TFESK, 85.2 g, 0.39 mol) and
deionized water (150 mL) were stirred magnetically at 25 C until
the solid dissolved. In a separate 500 mL flask,
tetradecyl(tri-n-butyl)phosphonium chloride (168 g, 0.39 mol
Cyphos.RTM. IL 167; Cytec (West Paterson, N.J.)) was first melted
by heating to 50 C, and then added to the TFESK solution to produce
an oily precipitate. The flask was stirred at 25 C for another 19 h
to allow complete precipitation of the product.
[0115] Chloroform (500 mL; Alrich) was added to the mixture which
was stirred for another 30 min. The chloroform layer, which
contained the product, was separated and set aside. The aqueous
layer was extracted with chloroform (5.times.20 mL washes) and
these aliquots were combined with the original chloroform layer.
The combined chloroform solution was washed with a saturated
aqueous sodium carbonate solution (5.times.20 mL washes; Aldrich),
followed by washes with deionized water (5.times.20 mL) until the
final wash water had pH=8.
[0116] The solution was dried over anhydrous magnesium sulfate
(Aldrich), at which point 10 g of decolorizing carbon was added to
remove colored impurities. This solution was stirred for another 30
minutes before being filtered through a 6-inch column packed
celite/basic alumina column to remove the carbon. The solution was
again dried over anhydrous magnesium sulfate (Aldrich) and
concentrated on a rotovap and then further dried (60 milliTorr, 25
C, 8 h.) to give the [4.4.4.14]P-TFES product as a clear light
yellow oil (173 g, 77% yield).
[0117] .sup.19F NMR (CDCl.sub.3) .delta. -124.3 (dt,
.sup.3J.sub.FH=6 Hz, .sup.3J.sub.FF=8 Hz, 2F); -136.0 (dt,
.sup.2J.sub.FH=53 Hz, 2F).
[0118] .sup.1H NMR (CDCl.sub.3) .delta. 0.8 (t, J=7.0 Hz, 3H); 1.0
(t, J=7.0 Hz, 9H); 1.3 (br s, 20H); 1.5 (m, 16H); 2.2 (m, 8H); 6.2
(tt, .sup.2J.sub.FH=53 Hz, .sup.3J.sub.FH=6 Hz, 1H).
[0119] % Water by Karl-Fisher titration: 594 ppm.
Example 1
Flame Retardancy of Polycarbonate Resin (Comparative Example)
[0120] Polycarbonate resin (1484.5 g; sold under the trade name
Lexan.RTM.HF-1110 (General Electric Co., Pittsfield, Mass.)) was
placed into a V-Cone blender fitted with intensifier bar (Patterson
Kelly, East Stroudsburg, Pa.). The resin was coated with 4 g of
poly dimethyl siloxane DC-200-60M (Dow Corning, Midland, Mich.).
After allowing the coating to adhere to the resin for 5 minutes,
the coated polycarbonate pellets were fed into a 30 mm twin screw
extruder (Werner-Pfleiderer, Coperion, Ramsey, N.J.) at 275 C. The
compounded polycarbonate was injection molded on a 1.5 ounce Arburg
injection molding machine (Newington, Conn.) fitted with a 1/16
inch (approximately 1.59 mm) ASTM (ASTM International, West
Conshohocken, Pa.) single gated flex bar mold. The samples were
stored in a room at 22 C and 50% relative humidity for a minimum of
1 day prior to being tested for flame retardancy.
[0121] All samples were tested according to standard flame
retardancy test procedure UL-94 (Underwriters Laboratories, Inc.,
Northbrook, Ill.). Test specimens were tested in the vertical
position. The regulated flame was placed onto a test specimen for
10 seconds and the time measured until the flame self extinguished
was recorded as t1. The flame was put onto the bar again test
specimens for 10 seconds and removed, and the second burn time was
recorded as t2. The presence of burning drips was also noted. No
afterflame was noted on any test sample when the flame was removed.
The criteria used for classifying the samples as V-0, V-1 or V-2
are shown in Table 1, wherein t1 and t2 are reported in seconds.
The results are shown in Table 2.
TABLE-US-00001 TABLE 1 Criteria used for classifying samples as
V-0, V-1 or V-2. Times for V-0, V-1 and V-2 are in seconds.
Criterion V-0 V-1 V-2 Afterflame time for each <10 <30 <30
individual specimen t1 or t2 Total afterflame time for any <50
<250 <250 condition set (t1 plus t2 for 5 specimens) Cotton
indicator ignited by No No Yes flaming particles or drops
Example 2
Flame Retardancy of Polycarbonate Resin Plus Antidrip Agent
(Comparative Example)
[0122] The procedure of Example 1 was repeated, however
poly-tetrafluoroethylene (p-TFE) antidrip agent (7 g; MP1400, E.I.
DuPont, Wilmington Del.) was added. The results are shown in Table
2.
Examples 3-6
Flame Retardancy of Polycarbonate Resin Plus Salt
[0123] The procedure of Example 2 was repeated except that, in
addition to the p-TFE, 4.5 g of a salt were added as indicated. The
results are shown in Table 2.
TABLE-US-00002 TABLE TWO Flame retardancy testing of polycarbonate
with or without anti-drip agent and/or salt. Example Flaming Number
Sample t1 t2 Drip Classification 1 Resin 9.5 3.2 Yes V-2 2 p-TFE
7.5 2.4 Yes V-2 3 TBP-HFPS 1.0 2.4 No V-0 4 HFPS-K 2.4 9.0 No V-0 5
TPES-K 4.3 2.4 No V-0 6 BMIM-TFES 0.9 0.8 No V-0 All values in
Table 2 are the average of 5 measurements. Abbreviations: TBP-HFPS,
n-butyl phosphonium 1,1,2,3,3,3-hexafluoropropanesulfonate; HFPS-K,
potassium 1,1,2,3,3,3-hexafluorpropanesulfonate; TPES-K, potassium
1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate; BMIM-TFES,
1-butyl-3-methylimidazolium 1,1,2,2 tetrafluoroethane
sulfonate.
Examples 7-14
Flame Retardancy of Polycarbonate Resin Plus Salt
[0124] Polycarbonate samples (specimens) were compounded as
described in Example 1 using 3000 ppm salt as indicated in Table 3
below and 5000 ppm p-TFE micropowder. The compounded polycarbonate
was further molded into bars as described in Example 1. The test
samples were tested according to UL-94 as described previously. The
results are shown in Table 3.
TABLE-US-00003 TABLE THREE Flame retardancy testing of
polycarbonate. Example Number Sample t1 t2 7 Resin + p-TFE only
13.5 23.0 8 TFES-K 1.1 2.0 9 BMIM-TFES 1.5 1.5 10 BMIM-NONA 1.0 1.0
11 TBP-TFES 4.3 1.0 12 BMIM-TFES 4.0 1.5 13 [4.4.4.14]P-TFES 3.0
1.0 14 BMIM-NONA 2.0 1.0
Examples 15-20
The Effect of Salt Concentration on Flame Retardancy of
Polycarbonate Samples
[0125] The effect of salt concentration on flame retardancy was
determined. Polycarbonate samples (specimens) were compounded with
5000 ppm p-TFE micropowder as described in Examples 7-14 using
BMIM-TFES or TFES-K as the salt at concentrations indicated in
Table 4 below. The compounded polycarbonate was further molded into
bars as described in Example 1. The test samples were tested
according to UL-94 as described previously. The results are shown
in Table 4.
TABLE-US-00004 TABLE FOUR Flame retardancy testing of
polycarbonate. Salt Example Conc. Number Sample (ppm) t1 t2 15
BMIM-TFES 3000 1.0 0.6 16 BMIM-TFES 1500 0.8 0.0 17 BMIM-TFES 750
0.4 0.2 18 TFES-K 3000 0.8 2.4 19 TFES-K 1500 1.0 3.0 20 TFES-K 750
1.0 1.3
* * * * *