Note: Descriptions are shown in the official language in which they were submitted.
7~
- 1 - RD 17480
SOLVENT RESISTANT, COMPATIBLE BLENDS OF
POLYPHENYLENE ETHERS AND LINEAR POLYESTERS
This invention relates to novel resinous
compositions with high impact resistance, solvent resistance,
tens.ile strength and thermal stability. More particularly,
it relates to improved compositions comprising polyphenylene
ethers and linear polyesters.
The polyphenylene ethers are a widely used
class of thermoplastic engineering resins characterized by
excellent hydrolytic stability, dimensional stability,
toughness, heat resistance and dielectric properties.
They are also resistant to high temperature conditions
under many circumstances. Because of the brittleness of
many compositions containing polyphenylene ethers, they
are frequently blended with impact modifiers such as
elastomers to form molding compositions.
A disadvantage of the polyphenylene ethers
which militates against their use for molding such items
as automotive parts is their low resistance to non-polar
solvents such as gasoline. For increased solvent
resistance, it would be desirable to blend the poly-
phenylene ethers with resins which have a high degree of
crystallinity and therefore are highly resistant to solvents.
Illustrative of such resins are the linear polyesters
including poly(alkylene dicarboxylates), especially the
poly(alkylene terephthalates). However, such blends
frequently undergo phase separation and delamination.
They typically contain large, incompletely dispersed
:
:;
: .
-' .
~6~ 7~.
- 2 - RD 17~0
polyphenylene ether particles and no phase interaction
between the -two resin phases. Molded parts made from
such blends are typically characterized by extremely low
impact strength.
The present invention provides polymer blends
having a high degree of impact resi.stance and solvent
resistance. It also provides highly compatible polymer
blends containing polyphenylene ethers and poly(alkylene
dicarboxylates)l and resinous molding compositions
suitable for use in the fabrication of automotive parts and
` the like.
The invention is based on the discovery of a new
genus of compatible blends containing polyphenylene
ethers and poly(alkylene dicarboxylates~ in weight
ratios as high as l:l, or even higher under certain
circumstances, and a method for their preparation.
According to the invention, there are also incorporated
in the resinous composition an impact modifier and
a compatibilizing agent containing a substantial
proportion of aromatic polycarbonate structural units.
In one of its aspects, therefore, the
~- invention is directed to resinous compositions
comprising the following resinous components and any
reaction products thereof, all percentage proportions
; 25 being by weight of total resinous components:
~ (A) about 10-45% of at least one polyphenylene
-~` ether, or a blend thereof with at least one polystyrene;
(B) about 10-45% of at least one poly(alkylene
dicarboxylate), the wei~h* ratio of component A to
component B being at most 1.2:1;
(C) about 8-25% of at least one elastomeric
polyphenylene ether-compatible impact modifier; and
(D) from 3% to about 40% of at least one
polymer containing a substantial proportion of aromatic
polycarbonate units and having a weight average molecular
weight o~ at least about 40,000 as determined by gel
'74'~1
- 3 - RD 17480
permeation chromatography relative to po:lystyrene,
or a blend thereof with a styrene homopolymer.
It is not certain whether any or all of the
components in these compositions interact chemically
upon blending. Therefore, the invention includes
compositions comprising said components and any reaction
products thereof, as well as other optional components
described hereinaEter.
The polyphenylene ethers (also known as
polyphenylene oxides) used as all or part of component A
in the present invention comprise a plurality of
structural units having the formula
( ) ~ O --
Q Ql
In each of said units independently, each Ql is
independently halogen, primary or secondary lower
alkyl (i.e., alkyl containing up to 7 carbon atoms),
phenyl, haloalkyl, aminoalkyl, hydrocarbonoxy, or
halohydrocarbonoxy wherein at least two carbon atoms
separate the halogen and oxy~en atoms; and each Q is
independently hydrogen, halogen, primary or secondary
lower alkyl, phenyl, haloalkyl, hydrocarbonoxy or
halohydrocarbonoxy as defined for Q . Examples of
suitable primary lower alkyl groups are methyl, ethyl,
n-propyl, n~butyl, isobutyl, n-amyl, isoamyl,
2-methylbutyl, n-hexyl, 2,3-dimethylbutyl, 2-, 3- or
4-methylpentyl and the corresponding heptyl groups.
Examples of secondary lower alkyl groups are isopropyl,
sec-butyl and 3-pentyl. Preferably, any alkyl radicals
are straight chain rather than branched. Most often,
each ~l is alkyl or phenyl, especially Cl 4 alkyl, and
:
- 4 - RD 17480
each Q2 is hydroyen. Suitable polyphenylene ethers
are disclosed in a large number of patents.
Both homopolymer and copo]ymer polyphenylene
ethers are included. Suitable homopolymers are those
containing, for example, 2,6-dimethyl-1,4-phenylene
ether units. Suitable copolymers include random
copolymers containing such units in combination with
(for example) 2,3,6-trimethyl-1,4-phenylene ether
units. Many suitable random copolymers, as well as
homopolymers, are disclosed in the patent literature.
Also included are polyphenylene ethers
containing moieties which modify properties such as
molecular weight, melt viscosity and/or impact
strength. Such polymers are described in the patent
~ 15 literature and may be prepared by grafting onto the
-~ polyphenylene ether in known manner such vinyl monomers
as acrylonitrile and vinylaromatic compounds (e.g.,
styrene~, or such polymers as polystyrenes and
- elastomers. The product typically contains both grafted
and ungrafted moieties. Other suitable polymers are
the coupled polyphenylene ethers in which the coupling
agent is reacted in known manner with the hydroxy groups
of two polyphenylene ether chains to produce a higher
; molecular weight polymer containing the reaction product
of the hydroxy groups and the coupling agent. Illus-
trative coupling agents are low molecular weight
polycarbonates, quinones, heterocycles and formals.
The polyphenylene ether generally has a
number average molecular weight within the range of
30 about 3,0Q0-40,000 and a weight average molecular
; weight within the range of about 20,000-80,000, as
determined by gel permeation chromatography. It
intrinsic viscosity is most often in the range of about
0.15-0.5 and preferably at least 0.25 dl./g., as
measured in chloroform at 25C.
The polyphenylene ethers are typically
~7~7~iL
- 5 - RD 17480
prepared by the oxidative coupliny of at least one
corresponding monohydroxyaromatic compound. Particularly
use~ul and readily available monohydroxyaromatic
compounds are 2,6-xylenol (wherein each Q1 is methyl
and each Q is hydrogen), whereupon the polymer may
be characterized as a poly(2,6-dimethyl-1,4-phenylene
ether), and 2,3,6-trimethylphenol (wherein each Ql and
one Q2 is methyl and the other Q2 is hydrogen).
A variety of catalyst systems are known for
the preparation of polyphenylene ethers by oxidative
coupling. There is no parkicular limitation as to
catalyst choice and any of the known catalysts can
be used. For the most part, they contain at least one
heavy metal compound such as a copper, manganese or
cobalt compound, usually in combination with various
other materials.
A first class of preferred catalyst systems
consists of those containing a copper compound. Such
catalysts are disclosed, for example, in U.S.
Patents 3,306,874, issued February 28, 1967 to Hay,
3,306,875, issued February 23t 1967 to Hay,
3,914,266, issued October 21, 1975 to Hay, and
4,028,341, issued June 7, 1977 to Hay. They are
usually combinations of cuprous or cupric ions,
halide (i.e., chloride, bromide or iodide) ions and
at least one amine.
Catalyst systems containing manganese compounds
constitute a second preferred class. They are generally
alkaline systems in which divalent manganese is
combined with such anions as halide, alkoxide or
phenoxide. ~ost often, the manganese is present as
a complex with one or more complexiny and/or chelating
ayents such as dialkylamines, alkanolamines, alkylene-
diamines, o-hydroxyaromatic aldehydes, o-hydroxyazo
compounds, ~-hydroxyoximes (monomeric and polymeric),
o-hydroxyaryl oximes and ~-dikekones. Also useful
- 6 - RD 17480
are known cobalt-containiny catalyst systems. Suitable
manganese and cobal-t-containing catalyst systems for
polyphenylene e-ther preparation are known in the ar-t
by reason of disclosure in numerous pa-tents and
publications.
The polyphenylene ethers which may be used
in -the invention include those which comprise molecules
having at least one of the end groups of the formulas
N(R2)2
Q2 C(R )2
(II) ~ O ~ O~ and
Q2 Ql
Ql Q2 Q2 Ql
~ O ~ ~ OH
Q 2 Q2 Ql
wherein Ql and Q2 are as previously defined; each Rl
is independently hydrogen or alkyl, with the proviso
that the total number of carbon atoms in both Rl radicals
is 6 or less; and each R2 is independently hydrogen or
a Cl 6 primary alkyl radical. Preferably, each Rl is
hydrogen and each ~ is alkyl, especially methyl or
n-butyl.
Polymers containing the end groups of
formula II (hereinafter "aminoalkyl end groups") may
obtained by incorporating an appropriate primary or
secondary monoamine as one of the constituents of
; the oxidative couplin~ reaction mixture, especially
when a copper- or manganese-containing catalyst is used.
7~
- 7 ~ RD 17480
Such amines, especially the dialkylamines and preferably
di-n-bu-tylamine and dimethylamine, frequently become
chemically bound to the polyphenylene ether, mos-t often
by replacing one of the d-hydrogen atoms on one or more
Ql radicals. The principal site of reaction is the
radical adjacent to the hydroxy group on the terminal
unit of the polymer chain. During further processing
and/or blending, the aminoalkyl end groups may undergo
various reactions, probably involving a quinone methide-
type intermediate of the formula
Q ~ (R )2
(IV) - O ~ / ~ O
Q2 ~ Ql
with numerous beneficial effects often including an
increase in impact strength and compatibilization with
other blend components. Reference is made to
15 U.S. Patents 4,054,553, issued October lS, 1977 to Olander,
4,092,294, issued May 30, 1978 to Bennett Jr., et al,
4,477,649, issued October 16, 1984 to Mobley,
4,477,651, issued October 16, 1984 to White et al, and
4,517,341, issued May 14, 19~5 to White.
Polymers with 4-hydroxybiphenyl end groups
of formula III are typically obtained from reaction
mixtures in which a by-product diphenoquinone of the
formula
Q Q2 Q2 Q1
(V) 0~0
is present, especially in a copper-halide-secondary or
tertiary amine system. In this regard, the disclosure
~4 ~1
- 8 R~ 17~0
of the aforementionecl U.S. Patent 4,~77,649 is again
pertinent as are those oE U.S~ Patents 4,23~,706,
issuecl November 18, 1980 to White and 4,482,697, issued
November 13, 1984 to Haitko. In mixtures of this type,
the diphenoquinone is ultimately incorporated into
the polymer in substantial proportions, largely as an
end group.
In many polyphenylene ethers obtained under
-the above-described conditions, a substantial proportion
of the polymer molecules, typically constitutiny as much
as about 90% by weight of the polymer, contain end yroups
having one or frequently both of the formulas II and III.
It should be understood, however, that other end groups
may be present and that the invention in its broadest
sense may not be dependent on the molecular structures
of the polyphenylene ether end groups.
It will be apparent to those skilled in the
art from the foregoing that the polyphenylene ethers
contemplated for use in the present invention include
all those presently known, irrespective of variations
in structural units or ancillary chemical features.
The use of polyphenylene ethers containing
substantial amounts of unneutralized amino nitrogen
may, under certain conditions, afford compositions
with undesirably low impact strengths. The possible
reasons for this are explained hereinafter. The amino
compounds include, in addition to the aminoalkyl end
groups, traces of amine (particularly secondary amine)
in the catalyst used to form the polyphenylene ether.
It has further been found tha-t the properties
of the compositions can often be improved in several
respects, particularly impact strength, by removing or
inactivating a substantial proportion of the amino
compounds in the polyphenylene ether. Polymers so treated
are sometimes referred to hereinafter as "inactivated
"inactivated polyphenylene ethers". They preferably
,
'
7'~
- 9 ~ RD 17480
contain unneutralized amino nitrogen, if any, in amounts
no greater than 800 ppm. and more preferably in the
range of about 200-800 ppm. Various means for
inactivation have been developed and any one or more
thereof may be used.
One such method is to precompound the poly-
phenylene ether with at least one non-volatile compound
containing a carboxylic acid, acid anhydride or ester
group, which is capable of neutralizing the amine
compounds. This method is of par~icular interest in the
preparation of compositions of this invention having
high resistance to heat distortion. Illustrative acids,
anhydrides and esters are citric acid, malic acid,
agaricic acid, succinic acid, succinic anhydridej maleic
acid, maleic anhydride, citraconic acid, citraconic
anhydride, itaconic acid, itaconic anhydride, fumaric
acid, diethyl maleate and methyl fumarate. Because of
their relatively high reactivity with amino compounds,
the free carboxylic acids and especially fumaric acid
are generally most useful.
Reaction of the polyphenylene ether with the
acid or anhydride may be achieved by heating at a
temperature within the range o~ about 230-390C, in
solution or preferably in the melt. In general, about
0.3-2.0 and preferably about 0.5-1.5 part (by weight) of
acid or anhydride is employed per 100 parts of
polyphanylene ether. Said reaction may conveniently be
carried out in an extruder or similar equipment.
Another method of inactivation is by extrusion
of the polyphenylene ether under the above~described
conditions with vacuum venting. This may be achieved
either in a preliminary extrusion step (which is
sometimes preferred) or during extrusion of the
composition o~ this invention, by connecting the vent of
the extruder to a vacuum pump capable o~ creating a
pressure of about 20 torr or less.
4'7~
- 10 - RD 17480
It is believed that these lnactivation methods
aid in the removal by evaporation or the neutrali~ation
of any traces of free amines (predominantly secondary
amines) in the polymer, including amines yenerated by
conversion of aminoalkyl end groups to quinone methides
of the type represented by formula I~. Polyphenylene
ethers havin~ a free amine nitrogen content below about
600 ppm. have been found particularly useful in this
invention. However, the invention is not dependent on
any theory of inactivation.
The preparation of inactivated polyphenylene
ethers by reaction with acids or anhydrides, together
with vacuum venting during extrusion, is illustrated
by the following examples. All parts in the examples
herein are by weight.
Exampl'e 1
A mixture of 1.43 parts of maleic anhydride
and 100 parts of a poly(2,6-dimethyl-1,4-phenylene e-ther)
having a number average molecular weight (as determined
by gel pexmeation chromatography) of about 20,000 and an
intrinsic viscosity in chloroform at 25C of 0.~6 dl./g.
was tumble-mixed for 15-30 minutes and then extruded on
a 20-mm. twin screw extruder at 400 rpm. over a temperature
' range of about 310-325C. The feed rate of the mixture
was about 524 grams per 10 minutes. The extruder was
vacuum vented with a vacuum pump to a pressure less
than 20 torr during the extrusion. The product was the
desired inactivated polyphenylene ether.
Examples'2-5
The procedure of Example 1 was repeated,
substituting Q.7, 0.8, 1.0 and 1.~ parts (respectively)
of fumaric acid for the maleic anhydride and extruding
over a temperature range of about 300-325C. A similar
product was obtained.
Example' 6
, .
The procedure of Example 2 was repeated,
~l~6~7~
~ 11 - RD 17480
substituting 0.7 part of citric acid Eor the fumaric
acid. Similar products were obtained.
Component A may also contain at least one
polystyrene. The term "polystyrene" as used herein
includes polymers preparad by methods known in the art
including bulk, suspension and emulsion polymerization,
which contain at least 25~ by weight of structural units
derived from a monomer of the formula
R3 - C = CH
1 2
(IV) ~
~ (Z)p
wherein R3 is hydrogen, lower alkyl or halogen; Z is
vinyl, halogen or lower alkyl; and p is from 0 to 5.
These resins include homopolymers of styrene, chloro-
styrene and vinyltoluene, random copolymers of styrene
with one or more monomers illustrated by acrylonitrile,
butadiene, ~-methylstyrene, ethylvinylbenzene, divinyl-
benzene and maleic anhydride, and rubber-modified
polystyrenes comprising blends and grafts, wherein the
rubber is a polybutadiene or a rubbery copolymer of about
98-70% styrene and about 2 30% diene monomer. ~hese
rubber-modified polystyrenes include high impact
polystyrene, or HIPS.
The proportion of polystyrene in component A is
not critical, since polyphenylene ethers and polystyrenes
are miscible in all proportions. Component A will gener-
ally contain about 5-50% (by weight) polystyrene, if any.
Component B is at least one linear polyester.
The linear polyesters include thermoplastic poly-
(alkylene dicarboxylates) and alicyclic analogs thereof.
They typically comprise structural units of the formula
O O
(VII) _ 0 - R4 _ 0 _ g _ Al C - ,
A''. i ;~
7~L
- 12 - RD 17480
wherein R4 i5 a sa-turated divalent aliphatic or alicyclic
hydrocarbon radical containing about 2-10 and ~Isually
about 2-6 carbon atoms and A1 :is a divalent aromatic
radical containing about 6-20 carbon atoms. They are
ordinarily prepared by the reaction of at least one diol
such as ethylene glycol, l,~-butanediol or 1,4-cyclo-
hexanedimethanol with at least one aromatic dicarboxylic
acid such as isophthalic or terephthalic acid, or lower
alkyl ester thereof. The polyalkylene terephthalates,
particularly polyethylene and polybutylene terephthalate
and especi~lly the latter, are preferred. Such poly-
esters are known in the art as illustrated by the
following patents: U.S. Patent 2,720,502, issued
October 11, 1955 to Caldwell, U.S. Paten-t 2,727,881,
. 15 issued December 20, 1955 to Caldwell et al,
- U.S. Patent 2,822,348, issued February 4, 1958 to Haslam,
U.S. Patent 3,047,539, issued July 31, 196~ ta Pengilly,
~ U.S. Patent 3,671,487, issued June 20, 1972 to Abolins,
U.S. Patent 3,953,394, issued April 27, 1976 to Fox et al,
20 and U.S. Patent 4,128,526, issued December 5, 1978 to
Borman.
Because of the tendency of polyesters to
undergo hydrolytic degradation at the high extrusion and
molding temperatures encountered by the compositions of
this invention, it is preferred that the polyester used
as component s be substantially free of water.
The polyesters generally have number average
molecular weights in the range of about 20,000-70,000,
. as determined by intrinsic viscosity (IV) at 30C in a
- 30 mixture of 60% (by weight) phenol and 40% 1,1,2,2-
tetrachloroethane. When resistance to heat distortion
is an important factor the polyester molecular weight
should be relat.ively high, typically above about 40,000.
Because of the presence of both poly(alkylene
dicarboxylates) and polymers containing carbonate
uni-ts in the compositions of this invention, there is
- 13 - RD 17480
a possibility for ester-carbonate exchange resulting in
degrada-tion oE one or bo-th polymers, particularly at
high molding -temperatures. It is, therefore, sometimes
preferred to incorporate in the compositions an agent
which suppresses such exchan~e, typically in the amount
of about 0.01-7.5% by weight of total polyester. It is
generally preferred to precompound said exchange suppressing
agent with the polyester, since it is frequently found
that the impact strengths of the compositions of this
invention are substantially decreased if the exchange
suppressing agent is incorporated directly therein.
Precompounding may be achieved by direct blending or
by forming a concentrate, typically with about 1-25%
by weight of the polyester, and adding said concentrate
to the remaining portion thereof.
Illustrative exchange suppressing agents are
hydroxyaromatic compounds such as the hydroxybenzo-
phenones disclosed in U.S. Patent 4,452,932, issued
June 5, 19~4 to Brunelle; salicylate compounds such as
methyl salicylate, disclosed in U.S. Patent 4,452,933,
issued June 5, 19~4 to McCready; and sodium and
potassium dihydrogen phosphates disclosed in
U.S. Patent 4,532,290, issued July 30, 19~5 to Jaquiss
et al.
Component C is at least one elastomeric
polyphenylene ether-compatible impact modi~iex. Suitable
impact modifiers include various elastomeric copolymers,
of whic~ examples are ethylene-propylene-diene polymers
(EPDM's), both unfunctionalized and ~unctionalized
with (for example) sulfonate or phosphonate groups;
carbo~ylated ethylene-propylene rubbers; block copolymers
of alkenylaromatic compounds such as styrene with
polymerizable olefins or dienes, including butadiene,
isoprene, chloroprene, ethylene, propylene and butylene;
and core-shell elastomers containing, for example, a
poly(alkyl acrylate) core attached to a polystyrene
'' ' : ' '
4'7~
- 14 - RD 17480
shell via an interpenetrating network. Such core-shell
elastomers are more fully disclosed in U.S. Patent No.
4,681,915, issued July 21, 1987 to Bates et al.
The preferred impact modifiers are block
(typically diblock, triblock or radial teleblock)
copolymers of alkenylaromatic compounds and dienes. Most
often, at least one block is derived from styrene and at
least on~ other block from at least one of butadiene and
isoprene. Especially preferred are the triblock
copolymers with polystyrene end blocks and diene-derived
midblocks. It is frequently advantageous to remove
(preferably) or reduce the aliphatic unsaturation therein
by selective hydrogenation. The weight average molecular
weights of the impact modifiers are typically in the range
of about 50,000-300,000. Block copolymers of this type
are commercially available from Shell Chemical Company
under the trademark KRATON, and include KRATON DllO1,
G1650, G1651, G1652/ G1657 and G1702.
According to the present invention, the tendency
- 20 of blends of components A and B to be incompatible is
overcome by incorporating component D in the composition.
The essential ingrediant of component D is a polymer
containing a substantial proportion of aromatic
polycarbonate units.
~mong the preferred polymers of this type are
the aromatic polycarbonate homopolymers. The structural
units in such homopolymers generally have the formula
o
~ 2 ll
~VIII) -O - A - O - C -
wherein A2 is an aromatic radical. Suitable A~
values include m-phenylene, p-phenylene, 4,4'-bipheny-
lene, 2,2-bis(4-phenylene)propane, 2,2-bis(3,5-dimethyl-
4-phenylene)propane and similar radicals such as those
which correspond to the dihydroxyaromatic compounds
:
.
~2~it~7~
- 15 - RD 17480
disclosed by name or Eormula (generic or specific) in
U.S. Patent ~,217,438, issued August 12, 1980 to Brunelle
et al. Also included are radicals containing non-
hydrocarbon moieties. These may be substituents such
as chloro, nitro, alkoxy and the like, and also linking
radicals such as thio, sulfoxy, sulfone, ester, amide,
ether and carbonyl. Most often, however, all A2 radicals
are hydrocarbon radicals.
The A2 radicals preferably have the formula
(IX) -A3 - Y - A4 - ,
wherein each of A and A is a single-ring divalent
aromatic radical and Y is a bridging radical in which
one or two atoms separate A from A . The free valence
bonds in formula IX are usually in the meta or para
positions of A and A in relation to Y. Such A values
may be considered as being derived from bisphenols of
the formula ~o-A3-Y-A4OH. Frequent reference to bis-
phenols will be made hereinafter, but it should be
understood that A2 values derived from suitable compounds
other than bisphenols may be employed as appropriate.
In formula IX, the A3 and A values may be
unsubstituted phenylene or substituted derivatives
thereof, illustrative substituents (one or more) being
alkyl, alkenyl (e.g., crosslinkable-graftable moieties
such as vinyl and allyl), halo (especially chloro
and/or bromo), nitro, alkoxy and the like. Unsubstituted
phenylene radicals are preferred. Both A3 and A are
preferably p-phenylene, although both may be o- or
m-phenylene or one o- or m-phenylene and the other
p-phenylene.
'rhe bridging radical, Y, is one in which one
or two atoms, preferably one, separate A3 from A . It
is most often a hydrocarbon raidcal and particularly
a saturated radical such as methylene, cyclohexyl-
methylene, 2-[2.2.1]-bicycloheptylmethylene, ethylene,
2,2-propylene, 1,1-(2,2-dimethylpropylene), l,l-cyclo-
,
.
l~X.~
- 16 - RD 17480
hexylene, 1,1-cyclopentadecylene, l,1-cyclododecylene or
2,2-adamantylene, especially a gem-alkylene radical. Also
included~ however, are unsaturated radicals and radicals
which are entirely or partially composed of atoms other
than carbon and hydrogen. Examples of such radicals are
2,2-dichloroethylidene, carbonyl, thio and sulfone. For
reasons of availability and particular suitability for the
purposes of this invention, the preferred radical of
formula VIII is the 2,2-bis(4-phenylene)propane radical,
which is derived from bisphenol A and in which Y is
isopropylidene and A3 and A4 are each p-phenylene.
Various methods of preparing polycarbonate
homopolymers are known, and any of them may be used for
preparing component D. They include interfacial and other
methods in which phosgene is reacted with bisphenols,
transesterification methods in which bisphenols are
reacted with diaryl carbonates, and methods involving
conversion of cyclic polycarbonate oligomers to linear
polycarbonates. The latter method is disclosed in
European Patent Application 162,379 and in U.S. Patent No.
4,644,053, issued February 17, 1987 to Brunelle et al, and
in U.S. Patent No. 4~605,731, issued August 12, 1986 to
Evans et al.
Various copolycarbonates are also useful as
component D. One example thereof is the polyester-poly-
carbonates of the type obtained by the reaction of at
least one dihydroxyaromatic compound with a mixture of
phosgene and at least one dicarboxylic acid chloride,
aspecially isophthaloyl chloride, terephthaloyl chloride
or both. Such polyester-polycarbonates contain structural
units of formula VIII combined with units of the formula
O O
Il 5 11
(X) - O - C - A - C -
wherein A5 is an aromatic and usually a p- or m-phenylene
'~1
,
.
~67'1~
- 17 - RD 17480
radical. Other examples are the siloxane-carbonate block
copolymers dlsclosed, ~or example, in U.S. Patents
3,189,662, issued June 15, 1965 to Vaughn Jr. and
3,419,634, issued December 31, 1968 to Vaughn, Jr., and
the polyphenylene ether-polycarbonate block copolymers of
U.S. Patents 4,3374,224, issued February 15, 1983 to
Raamsdonk et al and 4,436,876, issued March 13, 1984 to
Loucks, which frequently provide compositions with
substantially higher heat distortion temperatures than
those containing homopolycarbonates.
The copolycarbonates should, for the most part,
contain at least about 202% by weight of carbonate
structural units. When the copolymeric units are other
than ester units, the polymer preferably contains at least
about 45% carbonate units.
The weight average molecular weight of the homo-
or copolycarbonate should be at least about 40,000 (as
determined by gel permeation chromatography relative to
polystyrene) for maximum impact strength. It is most
often in the range of about 40,000-80,000 and especially
about 50,000-80,000. However, compositions in which
component D has a molecular weight in the range of about
80,000-200,000 oten have very high impact strengths, as
noted hereinafter.
In most instances, component D consists of the
polycarbonate or copolycarbonate; that is, said polymer is
the entire component except for impurities. It is within
the scope of the invention, however, to use as component D
a blend of a polycarbonate or polyester-polycarbonate with
a styrene homopolymer, typically having a number average
molecular weight o~ about 50,000-250,000. Such blends
generally contain at least 50% o~ the polycarbonate or
polyester-polycarbonate.
It will be noted that various polystyrenes may
be used in the invention as all or part o~ components A, C
~` and D. However, tlle speci~ic polystyrenes used are
dif~erent in various respects. The polystyrene in
$1'',
7~71
- 18 - ~D 17480
componen-t ~ is a homopolymer, random copolymer or
rubber-modified polystyrene; component C may be a block
or core-shell copolymer; and homopolymers are used in
component D. Moreover, polystyrenes are ordinarily
present in only one of components A and D, if in either.
It is also within the scope of the invention
to employ a polyester-aromatic polycarbonate blend as
a source of part or all of components B and D. As
explained hereinafter, the use of such a blend may
provide somewhat more flexibility in component
proportions.
Particularly in compositions containing
inactivated polyphenylene ethers and relatively small
` amounts of polycarbonate, it is frequently found that
impact strength and/or resistance to heat distortion
are improved if there is also blended into the composi-
tion (E) at least one compound selected from those
containing at least one cyanurate or isocyanurate
; moiety and those containing a plurality of epoxide
moieties. Illustrative cyanurates and isocyanurates
are cyanuric chloride, triethyl cyanurate, triallyl
cyanurate, triallyl isocyanurate and triphenyl cyanurate.
Epoxide compounds include homopolymers of such
compounds as glycidyl acrylate and glycidyl methacrylate,
as well as copolymers thereof, preferred comonomers
being lower alkylacrylates, methyl methacrylate,
acrylonitrile and styrene. Also useful are epoxy-
substi-tuted cyanurates and isocyanurates such as
triglycidyl isocyanurate.
In various respects, the proportions of
ingredients in the compositions of this invention are
an important consideration. It is generally contemplated
that components A and B will be present in the compositions
described hereinabove in the amount of about 10-45~,
preferably about 15-45~, of total resinous components.
Moreover, the weight ratio of component A to component B
'
:', ~. ` ' '
.~ . . ~ . ~' , .
7:~
- 19 - RD 17480
should be at most 1.2:1, since if component A is present
in greater amounts the impact strength of the composition
may decrease sharply. Said weight ratio is preferably
about 0.7-1.0:1.
Component C, the elastomeric impact modifier,
may be present in the amount of about 8-25% and especially
about 10 20%. Since a decrease in tha proportion of
component C frequently increases heat distortion
temperature, the level thereof should be minimized if high
resistance to heat distortion is desired.
With respect to the proportion of component D,
the compatibilizing polymer, the invention includes three
major embodiments although species outside these
embodiments are also contemplated. The first embodiment
includes compositions containing about 10-40% of component
D. In such compositions, component A is typically a
polyphenylene ether which has not been inactivated. In
most instances, levels of components A, B and d of about
15-35% and 20-40% (respectively) are preferred in such
compositions for maximum impact strength.
When component A is not inactivated and
components B and D are suppliecl in full or in part by
a polyester-aromatic polycarbonate blend, it is
frequently possible to attain the desired high impact
strengths by using proportions of certain components
outside of those previously described. This is true
in at least two respects: The possibility of using a
lower proportion of component B with respect to
component A, and of employing more than 40% of
component D. Thus, another aspect of the present
invention is compositions comprising the following
components and any reaction products thereof: about
15-35% o~ polyphenylene ether as component A, about
~0-35% of component B, about 10-25% of component C and
from 12% to about 50% of at least one aromatic
'~f9
7~
- 20 - RD 17480
polycarbonate as component D, with the provisos that
all of component B and at least about 60% of component
D are supplied as a poly(alkylene dicarboxylate)-
aromatic polycarbonate blend, and that the weight ratio
of component A to component B is at most about 1~8:1
and preferably about 0.7-1.8:1.
In the second embodiment, component A is an
inactivated polyphenylene ether and the proportions of
components A and B are each about 30-45~. The
proportion of componenk D is about 3-10%, and the blend
may also include component E in the amount of about
0.1-3.0 and preferably at least about 0.25 part per 100
parts of total components A, B, C and D. This
embodiment is often characterized by relatively high
heat distortion temperatures.
It is within the scope of this second
embodiment to introduce component E by blending with
the other components in a single blending operation.
However, it is often preferred to premix component E
with component B, typically by dry mixing followed by
preextrusion. Such premixing incxeases the melt
viscosity of component B, probably by increasing
molecular weight, and frequently also increases the
impact strength of the composition of the invention.
In the third embodiment, component A is an
inactivated polyphenylene ether and the polycarbonate
has a weight average molecular weight in the range of
about 80,000-200,000, preferably about 150,000-200,000.
Compositions in which these polycarbonates and other
components are present in the same proportions as in
the second embodiment are generally charackerized by
high impact strengths even when component E is absent.
The chemical roles of the inactivated poly-
phenylene ether and of component E in the compositions
of this invention ar~ not ~ully understood, and any
~ ~.
7~7~
- 21 - RD 17480
reliance on chemical theory as a basls for the invention
is specifically clisclaimed. It is believed, however,
that the presence of more than a certain minimum
proportion of amino compounds in the polyphenylene ether
can cause degradation in the molecular weight of the
polycarbonate. Such amino compounds include, in addition
to the aminoalkyl end groups, traces of amines (particu-
larly secondary amine) in the catalyst used to form the
polyphenylene ether. If this is true, the removal or
neutralization of the greater part of such amino compounds
produces an environment in which high molecular weight
is maintained in the polycarbonate t thus maximizing its
effect as a compatibilizing agent.
The compositions of this invention have been
shown by scanning electron microscopy to consist
essentially of particles of polyphenylene ether
- (component A~ dispersed in a continuous polyester-
containing phase. The size and shape of said particles
varies with such factors as the proportion of poly-
phenylene ether in the composition. The elastomeric
impact modifier (component C) is present substantially
entirely in the disperse phase. By reason of the size
and shape of the disperse phase particles and/or
their degree of adhesion to the continuous phase, the
compositions are highly resistant to delamination and
similar types of failure under stress.
It is within the scope of the invention for
the composition to contain other conventional ingredients
such as fillers, flame retardants, pigments, dyes,
stabilizers, anti-static agents, mold release agents
and the like. The presence of other resinous components
is also contemplated. These include impact modifiers
compati~le with component B, such as various graft and
core-shell copolymers of such monomers as butadiene,
styrene, butyl acrylate and methyl methacrylate. It
is frequently preferred to preextrude such impact
- 22 - RD 17480
modifiers with component B prior to its u-tilization in
the invention. By this method, compositions having
improved ductility at low temperatures may be prepared.
~lso included as other resinous components are
other impact and processability modifiers for component
A, such as olefin copolymers. In general, the amoun-ts
of any other resinous components, if present, will not
exceed about 15% by weight of total resin.
The preparation of the compositions of this
invention is normally achieved by merely blending
the ingredients thereof under conditions adapted -for
the formation of an intimate blend. Such conditions
often include extrusion, which may be conveniently
effected in a screw-type or similar extruder which
applies a substantial shearing force to the composition,
thereby decreasing the particle size thereof. The
extrusion temperature is generally in the range of
about 100-325C.
The extrusion conditions may affect the
impact strength and other properties of the composition.
For example, it is sometimes found that the impact
strength of the composition is increased if it is
extruded more than once, thereby insuring effective
blending.
In another embodiment, a single extruder
is employed which has at least two ports for introduc-
tion of in~redients, one such port being downstream from
the other. Component A or any reactants for preparation
thereof and at least a portion of component C are
introduced through the first port and extruded, preferably
at a temperature in the range of about 300-350C. This
portion of the extruder is preferably vacuum vented.
The remaining ingredients are introduced
through the downstream port and extrusion is continued,
preferably at a lower temperature to minimize degradation
of components B and C. For further minimization of
- 23 - RD 17480
degradation, it may be advantageous to introduce a
portion of component C at this point. Typical extrusion
tamperatures at this stage are in the range of about
260-320C.
In ths following examples illustrating the
inventions, the blend constituents used were as follows:
Component A
PPE - a poly(2,6-dimethyl-1,4-phenylene ether)
having a number average molecular weight of
about 20,000 and an intrinsic viscosity in
chloroform at 25C of 0.46 dl./g; it was found
to contain about 1000 ppm. nitrogen.
Example 1, etc. - the products of the
designated examples. The product of Example 2
contained about 600 ppm. nitrogen.
Example 2 (etc.)- NVV - a product similar to
that of Example 2 (etc.) but prepared with
atmospheric rather than vacuum venting.
PPE W - PPE which has been extruded on a twin
screw extrude.r within the temperature range of
about 300-315C, with vacuum venting to a
maximum pressure of 20 torr; it contained 438
ppm. nitrogen.
~; Component B
PBT (50,000) and PBT (25,000) - poly(butylene
terephthalates) having number average
molecular weights, as determined ~y gel
permeation chromatography, of about 50,000 and
; 25,000, respectively.
PBT-ES - PBT (50,000) containing NaH2P04 as
an exchange-suppressing agent. The NaH2P04
was preblended with a portion of the polyester
to a level of 1.8% by weight, after which 20%
of said polyester was blended with untreated
polyester.
PET (28,000) and PET (45,000) - poly(ethylene
terephthalates) having number average
molecular weights of about 28,000 and 45,000,
respectively, as determined from intrinsic
~0 viscosity at 30C in a 3:2 (by weight) mixture
o~ phenol and 1,1,2,2-tetrachloroethane.
;
:
.
t7~
- 2~ - RD 17480
Component C
S~BS - a commercially available triblock
copolymer with polystyrene end blocks
llaving weight average molecular weights
of 29,000 and a hydrogenated butadiene
midblock having a weight average molecular
weight of 116,000.
SBS - a triblock copolymer similar to SEBS
but containing an unhydrogenated butadiene
midblock.
SB(H) - a styrene-butadiene diblock copolymer
having a weight average molecular weight
o~ about 164,000 and a butadiene-styrene
weight ratio of about 2:1, in which the
butadiene block has been hydroganated.
SI(~) - a diblock copolymer similar to
SB(H~ but containing a hydrogenated isoprene
block.
CS - a core-shell polymer with a poly(butyl
acrylate~ core and polystyrene shell,
connected via an interpenetrating network.
:
Component D
PC(43,000), PC(50,000), PC(71,000~,
PC(192,000) - bisphenol A homopolycarbonates
prepared interfacially and having weight
averaye molecular weights of about 43,000,
50,000, 71,000 and 192,000, respectively.
PC-Trans - a bisphenol A homopolycarbonate
prepared by transesterification of diphenyl
carbonate and having a weight average molecular
weight o about 37,000.
S~-PC - a 2,2-bis(3,5-dimethyl-4-hydroxy-
phenyl~propane polycarbonate prepared
interfacially and having a weight average
molecular weight to about 50,000.
Allyl-PC - a copolycarbonate of 97.3 mole
percent bisphenol A and 2.7 mole percent
2,2-bis(3-allyl-4-hydroxyphenyl)propane,
prepared interfacially and having a weight
average molecular weight of about 47,000.
PPE-PC - a block poly(2,6-dimethyl-1,4-
phenylene ether)bisphenol A polycarbonate
copolymer in which the two blocks have
'
~ ~i7~'7~L
-- 25 -- ~D 17480
approximately equal molecular weights.
PE-PC - a polyester-polycarbonate containing
7~ mole percent polyester and 22 mole percent
polycarbonate units and having a weight
average molecular weight of about 50,000,
prepared by the interfacial reaction of
bisphenol A with phosgene and a 93:7 (by
weight) mixture of isophthaloyl and
terephthaloyl chloride.
PC-SIL - a block copolymer containing 76%
bisphenol A polycarbonate units and 24~
poly(dimethylsiloxane~ units, having a weight
average molecular weight of about 50,000.
PS - a commercially available styrene homopolymer
having a number average molecular weight of
about 106,000 and an intrinsic viscosity in
toluene at 25C of 0.80 dl./g.
Com~__ent E
TGIC - triglycidyl isocyanurate.
GMA - a glycidyl methacrylate homopolymer
having an intrinsic viscosity in chloro~orm
at 25C of 0.16.
GMA-AA(15) and GMA-AA(30) - commercially
available texpolymers of glycidyl methacrylate,
methyl methacrylate and a lower alkyl acrylate,
respectively containing 15~ and 30% (by weight)
glycidyl methacrylate ~lnits and having weight
average molecular weights of about 11,400
; and 9,000.
GMA-M - a commercially available copolymer of
glycidyl methacrylate (50% by weight) and
methyl methacrylate, having a weight average
molecular weight of about 10,000.
G~-S - a commercially available copolymer
of glycidyl methacrylate (50% by weight) and
styrene, having a weight average molecular
weight of about 11,000.
GMA-S-M - a commercially available terpolymer
of glycidyl methacrylate (50% by weight), styrene
and methyl methacrylate, having a weight average
molecular weight of about 10,000.
; GMA-S-A(lOA~, GMA-S-A(lOB), GMA-S-A(20) -
commercially available terpolymers of glycidyl
.
, .
.
:' ' ' `
:~ `
.
- 26 - RD 17480
methacrylate, styrene and acrylonitrile,
respectively containing 10%, 10% and 20%
(by weight) glycidyl methacrylate and
having weight average molecular weights
of about 8,700, 50,000 and 8,100.
Percentages and other proportions in the
examples are by weight and are based on total resinous
constituents. Impact and tensile values were
determined in British units and have been converted
to metric units. Heat distortion temperatures
are at 0.455 MPa. unless otherwise indicated.
~xamp'le's' 7-'13
A series of compositions according to
the invention was prepared by tumble mixing the
, 15 ingredients in a jar mil for 1/2 hour and
e~truding at 120-287C on a twin screw extruder
with a screw speed of 400 rpm. The extrudate
was quenched in water and pelletized. The
pellets were then injection molded into test
bars which were evaluated for notched Izod impact
~, strength according to ~STM procedure D256.
(An impact strength greater than about 105
joules/m. is generally àn indication o~ suitability
as a molding composition, and a value above
about 550 is exceptional.) Certain compositions
were also tested ~or heat ~istortion temperature
- according to ~STM procedure D648. The
- fracture surfaces of the Izod test bars were
inspected for delamination and none was detected.
The relevant parameters and test results
are given in Table I.
.
:
-
-
- 27 -RD 17480
TABLE I
_ Example 7 ~ 9 10 11 12 13
Component A: PPE, % 21 27 25 25 21 21 21
Component B, %:
PBT(50,000) 29 27 25 25 -~ -- 29
PET(28,000) -- -- -- -- 29 -- --
PET(45,000) ~~ ~~ ~~ ~ -- 29 --
Component C, %:
SEBS 14 13 19 -- 14 14 --
SI(H) -- ~~ ~~ 19 -- -_ __
SBS -- -- -- -- -- -- 14
Component D: PC(50,000), % 36 33 31 31 36 36 36
' Izod impact strength, joules/m. 603 160 609 550 198 278 598
The heat distortion temperature of the product
15 of Example 7 was 106C (83C at 1.82 MPa.).
Example 14
The effect of multiple extrusions and the
solvent resistance of a blend identical in composition
to that of Example 7 were tested. After one extrusion,
the blend had an Izod impact strength of 454 joules/m.;
upon extrusion a second time, the impact strength was
increased to 641 joules/m.
In a solvent resistance test, the test
specimen having an impact strength of ~41 joules/m.
' 25 was immersed in gasoline for two days under stress.
It was then found to have an impact strength of 214
joules/m., which is still a respectably high figure.
No signs of dissolution or deterioration were noted.
Exampl'es' 15-20
The procedure of Example 7 was repeated
using other resins as components B and D. The
relevant parameters and results are given in Table II.
No delamination of any specimen was observed.
~7~'~7~
- 28 - RD 17480
TABLE II
Example 15 16 17 1819 20
Component A: PPE, % 28 28 3131 34 34
Component B: PBT-ES, % 28 2831 31 34 34
5Component C: SEBS, % 1919 19 19 19 19
` Component D, %:
PC(50,000) 25 __ 19 __ 12 --
PC(71,000) -- 25 __ 19 __ 12
Izod impact stren~th, 625801 694790 139 112
joules/m.
Heat distortion temp., C 111 -- -- -- 127 --
Examples 21-28
The procedure o~ Example 7 was repeated,
using other resins as components B, C and D. The
relevant parameters and test resul-ts are given in
Table III. No delamination of any specimen was observed.
TABLE III
Example 21 22 23 24 25 26 27 28
Component A: PPE, % 21 2121 2821 34 3128
20Component B: PBT-ES, % 2929 2928 29 3431 28
Co~ponent C: SEBS, ~ 14 1414 1914 19 1319
Component D, %:
PC(43,000) 36 -- -- -- -- -- --
SH - PC - - 36 18 -- -- -- -- --
PE-PC __ __ __ -- 36 -- ~~ ~~
PPE-PC -- -- -- -- -- 12 25 25
PC-SIl -- -- -- 25 -- -- -- --
PS - 18
Izod impact strength,
joules/m. 176 278 182 449 251 117 764 732
Heat distortion temp., C -- -- -- -- 97 150 157 149
Referring specifically to Examples 26-27 in
comparison with Example 19, and Example 28 in comparison
with Example 15, it will be seen that compositions
containing block polyphenylene ether-polycarbonates have
,
.
- 29 - RD 17480
substantially higher heat distortion temperatures
than those containing homopolycarbonates, as well as
equivalent or higher impact strengths.
Examples 29-31
Following the procedure of Example 7, blends
were prepared in which component s was provided entirely
and component D entirely or partially by a polyester-
polycarbonate blend containing 39% PBT-ES, 49% PC(50,000),
8.5% of a commercial butadiene-styrene-methyl methacrylate
graft copolymer and 3.5% of various fillers and stabilizers.
The relevant parameters and results are given
in Table IV. No delamination of any specimen was observed.
TABLE IV
Example 29 30 31
. .
15Polyester-polycarbonate blend 64 32 50
Polycarbonate -- 32 14
Component A, % 21.7 21.5 21.6
Component B, % 25.8 12.7 20.0
Component C, % 14.5 14.3 14.4
20Component D, % 32.4 48.7 39.6
Graft copolymer, % 5.6 2.8 4.4
Izod impact strength, joules/m. 481 529 534
Examples ~32-3~
Compositions were prepared according to the
procedure of Example 7, except that the extrusion
temperature range was 120-260C. In these compositions,
component A was the product of Example 1 and the other
components are as listed in Table V.
Test bars were molded and evaluated for
notched Izod impact strength, heat distortion temperature
and tensile properties (ASTM procedure D638). The
relevant parameters and test results are also given in
Table V.
:
'
- 30 - RD 17480
TABLE V
Example 32 33 34
Component A:Example 1, % 40 41.4 40
Component B:PBT(50,000), % 40 41.4 40
- 5 Component C: SEBS, % 12 9.1 12
Component D:PC(50,000), % 8 8.1 8
Component E: TGIC, phr. -- 0.5 0.8
Izod impact strength, joules/m. 107 166 267
Heat distortion temp., C -- 166 156
Tensile strength a-t yield, MPa. 44.9 -- 46.0
Tensile elongation, % 45 -- 58
Example 35
Test bars of the composition of Example 34 were
immersed in gasoline for three days under stress. At
the end of this time, the Izod impact strength was 155
joules/m., the tensile strength at yield was 27.1 ~Pa.,
and the tensile elongation was 20%. Upon immersion of
similar test bars in water at room temperature or at
its boiling point for three days, and upon aging at
80C for one week, weight and dimensional changes
substantially less than 1% were observed.
Examples 36-43
Following the procedure of Example 32,
compositions were prepared from the product of Example
3 and its atmospherically vented counterpart. The
relevant parameters and test results are given in
Table VI. ~ _ _
/~ .
:
'
.'
, ::
3L2~
~ 31 - RD 17~80
. 10 ol ~1 COI oLr) I I I
I I I
CO ~
N O IO II N 0~ 1 0 ~~`J 1` O
~ LO
~1 o II o~ I I o~ o
0~
O ~ I~ IN I I ~ O IS~ I I I
I
.
~
`~ ~ o Io I ~ I I ct) o ~ co ~ o~
~ ~ ~ r I~ I I o
CO
: ~n
., OD O IO IN I CO I OCO 10 0 ~D
H r) ~ l I I ~ 1~Ltl O
:, ~ OD ~ ~
,, ~
:'' ~ ., O IO I ~ I 0~ ~ O ~ 00 1` ~
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` `. . ~9
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O I O I ~ I CO I O O ~
`~ :`. . r~
.
' ~ ~
' O ~ ~
~ o~
H ~:: ~ O
~.~ E~
:' o~ ~ o~ o~ o~ ~ O ~ (d
m o o C.~ o o
a) ~ ~ ~ , O O ,~ O o 1
o U~
O ~ ~ O E~ ~1 o m-- o---~ O .,, .,~
m m ~ ~ m ~
o
0 ~ ~ r~
.
- 3~ - RD 17480
Example 44
Test bars of the composition of Example 36 were
immersed in gasoline for four days under stress. At the
end of this time, the Izod impact strength was 769
joules/m., the tensile strength at yield was 33.9 MPa. and
the tensile elongation was 144%.
Examples 45-48
Rollowing the procedure of Example 32,
compositions were prepared in which components A, C and
D varied in additional respects. The relevant parameters
and test results axe given in Table VII.
TABLE VII
Example 45 46 47 48
.
Component A, %:
Example 6 40 -- -- --
PPE-VV ~~ 40 40 40
Component B: PBT(50,000), % 40 40 40 40
Component C, %:
SEBS 12 12 12 --
CS -- -- -- 12
Component D, %:
PC(50,000) 8 8 -- 8
PC(192,000~ -- -- 8 --
Component E: TGIC, phrØ8 0.5 -- 0.5
Izod impact strength, joules/m.785 769 764 486
Heat distortion temperature, C -- 167 -- --
Examples 49-51
- Following the procedure of Example 32,
compositions were prepared using as components B and D
the following preextruded blend:
PsT(50,000~ 69.55%
PC(50,000) 15%
PBT impact modifier 15%
Stabilizers, exchange suppressor 0.45%.
The PBT impact modifier was "KM-330", a poly(butyl
acrylate)-poly(methyl methacrylate) core-shell polymer
commercially available from RohM & Haas Company.
. ' `.-` ~'' ' '
~,:
- . ,
- 33 - RD 17480
The parameters and test results for Exarnples
49-51 are given in Table VIII.
TABL~ VIII
Example 49 50 51
Component A, %:
Example 3 36.6
RPE - W ---- 36.6 36.6
Component B, ~: 36.4 36.4 36.4
Component C: SEBS, % 11. 2 11. 2 11.2
Component D, %: 7.9 7.9 7.9
Component E: TGIC, phr. 0.4 0.4
K~-330, % 7-9 7 9 7 9
Izod impact strength, joules/m. 721 192 198
Example 52
-
~ twin screw extruder with two vacuum
vents and two charging ports, one downstream from
the other, was used. The first port was charged
with 30 parts of PPE, 14 parts of SEBS and minor
proportions of stabilizers and pigments. These
materials were extruded at temperatures in the
range of about 315-350C and pressures in the
range of about 150-205 torr. These were added
through the downstream port 46 parts of
PBT (50,000) and 10 parts of PC(71,000), and
extrusion was continued at temperatures in the
; range of 260-315C and pressures of about 635 torr~
The extrudate was the desired product.
EXamples 53-56
. . _
Following the procedure o~ Example 32,
compositions were prepared in which various poly-
carbonates were used as component D. The relevant
paxameters and test results are given in Table IX~
4'7-~
- 34 - RD 17480
TABLE IX
Example53 54 55 56
Component A, %:
PPE-VV 40 -- -- ~~
Example 2 -- 40 40 40
Component B: PBT(50,000) r %40 40 40 40
Component C: SEBS, % 12 12 12 12
Component D, %:
PC-Trans 8 8 8 --
Allyl-PC -- -- -- 8
Component E: TGIC, phr. -- -- 0.5 --
Izod impact strength, joules/m. 182 256 828 278
Examples 57-67
Following the procedure o~ Example 32,
compositions were prepared containing 40% of the
inactivated polyphenylene ether of Example 3, 40%
PBT(50,000~, 12% SEBS, 8% PC(50,000~ and, as
component E, various materials. The i~entity of these
materials and the test results are given in Table X.
~ 20 TABLE X
- Tensile
Izod strength Tensile
impact at elong-
Component E strength break ation,
25 Examp-le Identity Amt , phr. joules/m. MPa. %
57 -- - 219 38.8 45
58TGIC 0.8 673 42.7 78
59 GM~ 1.0 764 42.8 71
60GMA-AA(15) 1.0 657 41.7 50
61GMA-AA(30) 1.0 678 43.8 66
62GMA-S-M 1.0 609 47.9 79
63GMA-S 1.0 710 46.5 98
64GMA-M 1.0 587 48.2 86
65GMA-S-A(lOA) 1.0 657 41.4 53
66GMA-S-A(lOB) 1.0 684 40.2 49
67GMA-S-A(20) 1.0 646 43.2 65
The results in Table X show the improvement
in impact strength which results from the incorporation
o~ various species o~ component E in the compositions
of this invention. Such compositions containing component E
~7~7:~
- 35 - RD 17480
also have high impact strenyths at low temperatures. For
example, the composition o~ Example 67 had an Izod
impact strength a-t -40C of 198 joules/m.
Examples 68-70
5Blends similar to those o~ Examples 57-67 were
prepared, substituting PPE-W for the product of Example
2. The results are given in Table XI.
TABLE XI
~ Component E Izod impact
-: lo ExampleIdentity Arnt'.,- phr. - Strength, joules/m.
-
68 --- --- 294
69 GMA 1.0 680
70GMA-M 1.0 660
Examples 71-75
15These examples show the effect on polyester
melt viscosity of premixing the polyester with
component E. Premixing was effected by dry blending
followed by melt extrusion. The melt viscosities, or,
in some cases, melt fIow rates (which are inversely
, 20 proportional to melt viscosities) were compared with
those of controls which had been similarly extruded
without the addition of component E. The melt viscosity
~, of the polyester before extrusion was about 7,500 poises.
~, The relative parameters and test results are
-, 25 given in Table XII.
' TABLE'XII
, Melt
Component E Melt viscosity flow rate,
Example Identity Amt., % poises g./10 min.
30 Controls ~ - 5 t 900 38.7
71 TGIC 0.5 41,000 --
72 TGIC 1.0 135,000 --
73 GMA 1.0 --- 5.0
74 GMA-M 1.0 --- 3.4
75GMA-S-Al20~ 1.0 ~~~ 4 5
,
.~
` ~ ` ' '
.
:
~ 36 - RD 17~80
Examples 76-79
Following the procedure of Example 32,
compositions were prepared containing 40% of the
activated polyphenylene ether of Example 2, 40%
poly(butylene terephthalate) which had been premixed
with TGIC as described in Examples 71-75, 12% SEBS and
8% PC(50,000). They were compared with Controls I and
II prepared from untreated poly(butylene terephthalates),
and Control III, wherein the TGIC was dry blended with
all of the other components. The relative parameters
and test results are given in Table XIII.
.
1;~67~
- 37 - RD 17480
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- 38 - RD 17480
Example 80
__
This example c1emonstrates the effect on impact
strength of nitrogen content and molecular weight of the
polyphenylene ether. Blends were prepared by the
procedure of Example 32, using as component ~ two different
bisphenol A polycarbonates prepared interfacially and as
component A a number of polyphenylene ethers prepared by
procedures which did not include functionalization or
vacuum venting. Components B and C were PBT(50,000) and
SEBS, respectively. The results are given in Table XIV.
TABLE XIV
Izod
Polyphenylene ether Polycar- impact
IV, bonate strength
dl./g. Nitrogen! ppm. mol. wt. ioules/m.
0.46 1020 50,000 20
0.40 1115 " 20
0.29 497 " 78
0.1~ 353 " 22
0.53 576 " 57
0.46 1020 71,000 26
0.40 1115 " 26
0.29 497 " 115
0.18 353 " 22
0.53 576 " 265
It will be seen that comparatively high impact
strengths are obtained by using a polyphenylene ether
having a nitrogen content no greater than 800 ppm. and
an intrinsic viscosity of at least 0.25 dl./g.
Example 81
This example sho~s the effect of fumaric acid
level in the inactivated polyphenylene ether on the impact
strengths of the compositions. The procedure of Example 32
was employed to prepare compositions from 40% of various
fumaric acid-inactivated polyphenylene ethers, 40%
PBT(50,000~, 12% SEBS, 8% PC(50~000) and, in certain
cases, 0.32 phr. of TGIC. The impact strengths of the
compositions are given in Table XV.
74~7:~
- 39 - RD 17480
TABLE XV
Impact strength,
Polyphenylene ether TGIC loules~m~
Ex. 2 No 155
Ex. 4 No 198
Ex. 5 No 294
Ex. 2 Yes 700
Ex. 4 Yes 774
Ex. 5 Yes 726
; 10 It is apparent that increasing levels of
fumaric acid result in substantial increases in impact
strength in the absence of component e. The presence of
component E inherently causes such a profound increase
in impact strength that the effect of fumaric acid level
becomes insignificant.
Examples 82-84
Formulations having the weight ratios
indicated in Table XVI were prepared by blending and
; extrusion of the components on a Werner-Pfleiderer twin
screw extruder.
The extruder had two stages. The PPE,
polystyrene and half the SEBS were fed to the extruder
at its throat in order to ensure intimate mixing. This
first stage of the extruder had a set temperature of
about 350 to 360c and vacuum was applied to the melt.
The PBT, PC and remaining SEBS were fed down~tream at
the second stage of the extruder which had a set
temperature of about 240 to 250C. This second stage
provided adequate shear mixing of the components while
avoiding potential degradation of the components due to
exposure to high temperatures for longer periods.
The extrudate was quenched in water and
pelletized. The pellets were then injection molded into
test specimens which were evaluated for heat distortion
temperature, flow channel, Dynatup impact, notched Izod
impact and tensile yield and elongation. Test results
are given in Table XVI.
'' ' , ' '
~;~674~
- 40 - RD 17480
TA~LE XVI
Examples 82 83 84
Formulation
Component A, %:
PPE 31.3 28.3 28.3
Polystyrene homopolymera -- 9.4 --
HIpSb ____ 9.4
Component B: PBT(50,000), ~ 47.9 43.4 43.4
Component C: SEBS, % 12.5 11.3 11.3
10 Component D: PC(71,000), % 8.3 7.6 7.6
Properties
Heat distortion temperature, C 147 154 150
Flow channel, cm. 39.453.3 48.3
Dynatup impact, joules
room temperature 44.751.5 52.9
29C 47.550.2 56.9
Notched Izod, joules/m. 828 662 651
Tensile yield, MPa. 41.447.6 50.3
Tensile elongation, ~ 43 29 29
aShell 203 clear crystal polystyrene
bAmerican Hoechst 1897 rubber modified polystyrene
Examples 85-88
In this series o~ examples, blends were
prepared in the same manner as described above ~or
Examples 82-84. The weight ratio o~ the polyphenylene
ether to polystyrene (American Hoechst 1897 high impact
polystyrene) was varied. In this series, component B
was ~5% PB~(50,000), component C was 12~ SEBS and
component D was 8~ PC(71,000). Table XVII indicates
the manner in which the polyphenylene ether and the
polystyrene were varied and reports the results o~ the
physical property tests. It is evident that the
proportions o~ polyphenylene ether and polystyrene can
be ~idely varied ~nd still provide a variety o~ useEul
47~
- 41 - RD 17480
thermoplastic produc-ts.
TABLE XVII
Example 85 86 87 88Control
Formulation
Component A, %:
PPE 35 30 25 20 0
HIPS 0 5 10 15 35
Properties
Heat distortion
temperature, C 162 158 150 138 103
Flow channel, cm. 41.9 44.5 44.5 54.683.8
Dynatup impact, joules
Room temperature 50.2 47.5 54.2 50.2 17.6
-29C 62.4 66.4 54.2 47.5 --
Notched Izod, joules/m. 694 721 716 342 69.4
Flex. modulus, GPa. 1.85 1.90 1.91 1.85 1.70
Flex. strength, MPa. 68.3 68.9 68.964.8 49.6
Tensile yield, MPa. 46.2 49.0 45.548.3 29.6
Tensile elongation, % 33 30 43 36 8
;~
