Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
-1- 8CL 6041
COMPOSI~ION
BACKGROU~D OF T~E INVENTION
High molecular weight aro~atic carbonate polymers
(aromatic carbonate polymer3 are well known ~or th~ir
toughness as evidenced by their impact stxen~th and ot~er
high performance charackeristics. H~wever, because of
S their relative di~ficulty in processing as illustrakively
exemplified by the temperature ~ecessary to mold art}cles,
certain thin wall intricate articles useful in engineexirlg -
applications are ver~ difficult if no~ impossible to
. econ~mically mold~ Therefore, it would be ad~antageous
10 " to have an ~romatic carbonate pol~mer containing com-
posikion which is readily processable but substantially
maintains aromatic carbonate polymer toughness character-
iskics in thin section tes~ ~xsL~I~. Concurren~ upgrading o~
the toughness characteristics in khick section test
syste~s is also desirable.
.. DESCRXPTIO~ OF THE INVENTION
A new ~omposition has been discovered which has these
. aroresaid toughness characteristics of a~ aromatiG
: carbonate pol~mer buk is x~adily processable. In accord-
ance with the invenkion khere is a composition which com
prises
~ 2 '~ HCL-60~L
(a) an aromatic carbonate polymer,
(b~ ~ butadiene~styrene copolymer, and an
(c) acrylate copolymer which is a copol~er o~ a
Cl S acrylate and a Cl ~ methacrylate~
Another aspec~ of the invention is the addition of
an acrylate-olefin copolymer to the above composition.
This new quaternary composition has inGreased toughness
at low temperatures in comparison to the ternary com-
position.
Aromatic carbonate pol~mers in ~he sense of the
presenk in~ention are to be unders~ood as homopol~-
carbona~es and copolycarbonates and mixtures thereof
which have average molecular weights of a~ou~ 8,OGO
to moxe than200,000 preferably of a~out 20,000 to 80,000
lS . and an I.V. of 0~40 to 1.0 dl/g as measurPd in methylene
chloride at 25 C. These polycarbonates are deri~ed from
dihydric phenols such as, for example, 2,2-bi5(4-hydroxy
p~enyl) propane (bisphenol-A), bis(4-hydroxyphenyl)
methane, ~,2~bis(4-hydroxy-3-methylphenyl) propane, 4,4-
bis(4~hydroxyphenyl) heptane, 2,2-(3,5,3',5'-tetrachloro-
4,4'~dihydroxyphenyl) propane, ~,2-C3,5,3' r 5 1 -tetra-
bromo-4,4'-dihydroxydiphenyl~ propane, and (3,3'-di.chloro
4,4'-dihydroxydiphenyl) methane. Other dihydric phenols
, which are also suitable for use in the preparation of the
25 . above polycarbonates are disclosed in U~S~ Pa~ent Nos~
2,999,835~ 3,028,36S; 3,334,154 and 4,131,575~ Bisphenol- :
A is preferred~
. These aromatic polycarbonates can ~e manufactur2d by
! kno~n processes, such asy for example, by reac~ing a di
hydric phenol with a carbonate precursor such as phosgene
in accordance with methods set ~orth in t~e above-cited
literature and U.S. Patent Nos. 4~,018,750 and 4,123,436l
or ~y transesterification processes such as are disclosed
in U.S~ Patent No. 3,153,008, as we~l as other processes
~88C~Z~L 8CL-6041
--3--
kno-~n to -those skilled in the art~
The aromatic polycarbonates utilized in the present
invention also include the polymeric derivati~es of a di-
hydric phenol, a dicarboxylic acid, and car~onic acid,
or carbonic acid derivatives, for example, phosgene, such
as are disclosed in U.S. Patent No. 3,169,131.
It is also possible to employ two or more different
dihydric phenols or a copolymer of a dihydric phenol with
a glycol or with hydroxy or acid tenminated polyester, or
with a dibasic acid in the event a carbonate copolymer or
interpolymer rather than a homopolymer is desired for use
in the pxeparation of the aromatic po~ycarbonate utilized
in the practice of this invention~ Also employed in the
, practice of this in~ention can ~e blends of any of the
abo~e materials to provide the aromatic polycarbonate.
Branched polycarbonates, such a are de~cribed in
U~S. Patent No~ 4,001,184l can also ~e utilized in the
practice vf this invention, as can blends of a l; n~r
polycar~onate and a branched polycarbonate.
The preferred aromatic carbonate polymer is a homo-
polymex deri~ed from bisphenol-A as the dihydric phenol.
The "acxylate" copolymer utilized in the present
invention is a copolymer of a Cl-C5 methacrylate and a
. Cl-C5 acrylate, wherein the term "Cl-C5" represents both
25 ; saturated and unsaturated, straight or branched ch~ i n~d
`; aliphatic hydrocar~on radicals having from 1 to 5 carbon
atoms.
Preferred acrylates for use in the above copolymex
are methyl acrylate, ethyl acrylate, isobutyl acryla~e,
1,4 butanediol diacrylate, n-butyl acrylat~, and 1,3-
bu~ylene diacrylate. Preferred me~hacrylates for use in
this copolymer include methyl methacrylate, isobutyl meth-
acrylate, 1,3-butylene dimethacrylate, bu~yl methacrylate
~- and ethyl methacrylate.
The acrylate portion of the copolymer, based on the
total weight of the copolymer, can range from abou~ 50
to abou~ 85 weiyht percent. The methacrylate portion of
;
8~ acL~6r)~11
--4~
the copolymer can range from about 15 -to about 50 ~eight
percent .
The preferred acrylate copolymer for use in ~his
invention i.s a copolym~r of n-butyl acrylate and methyl
methacrylate in which the weight ratio of the n-butyl
acrylate fraction to ~he methyl methacrylate fraction in
the copolymer is about 3 to 2.
Suitable acrylate copolymers, as defined above, can
be prepared by methods well kno~m to those skilled in the
art or can be obtai~ed commercially~ For example, Rohm
and Haas' Acryloid~ KM 330 copolymer, which is a copolymer
o n-butyl acrylate and methyl me~hacrylate, is suita~le
for use in the pre~ent invention~
In the butadiene-styrene copolymer utilized herein,
15- the butadiene portio~ of the copolymer, based on the
: total w~ight o the copolymer, can range from about 15
to about 40 weight percent. The sLyrelle portion of the
! copolymer can range from about 60 to a~out 85 weight
percent.
In the preferred butadiene-styrene copolymer or use
herein, the weight ratio of the styrene fraction to the
; butadiene fra~tion ranges ~rom a~out 2 to 1 to about 3
~o 1.
Suitable ~utadiene-styrene copolymers, as de~ined
above, can be prepared by methods well known to thos2
~killed in the art or can be obtained commercially. For
example, Phillips Petroleum R-Resin~ RR03 BDS pol~mer is
suitable for use in the present invention.
The ~ourth pol~mer,.acrylate-olefin copolymer, when
present in the composition,is a copolymer o a C2-C5 olefin
and a Cl-C5 acrylate. The term "Cl-C5" is as defined above
and the term "C2-C5" represents a:s~raight or branched
chain aliphatic hydrocaxhon radical havin~ from 2 to 5
carbon atoms. The preferred oleEins are ethylene, propy~
8CL--60~1
--5--
lene and isobutylene. Preferred acrylates which ~re
utilized in the olefin-acrylate copolymer are ethyl
acrylate, n-butyl acrylate, l,3-butylene dia~rylate,
rnethyl acrylate, l,4-butanediol diacrylate and isobutyl
acrylate.
The acrylate portion of the olefin-acrylate co-
polymer, based on the total weight of the copolymer, can
range from about 10 to a~out 30 weiyht percent. The ole-
fin portion of the copolymer can range from about 70 to
about 90 weight percent.
The preferred ole~in-acrylate copolymex for use in
~his invention is an ethylene-ethyl acrylate copolymer,
in w~ih the weight ratio of the ethylen~ fraction to
' the ethyl acrylat~ fraction is about 4.5 to 1.
Suitable olefin-acrylate copolymers, as defined above,
can be prepared by methods well kn~wn to those skilled in
the art or can be obtained c. ~rcially~ For example,
Union Carbide7s Bakelite~ DPD-6169 eth~lene ethyl acrylate
copolymer i5 suitable for use in the present invention.
2a The amount of the ~utadiene-styrene copolymer presen~
in the composition of the present invention can range from
a~out six to about sixty percent, by weight, per hundred
parts of the total composition. Preferably, the ~u~adiene-
styrene copolymer is present in amounts of from about
25~' ten to about ~orty weight percent of the total composition.
i The amount of the acrylate copolymer present in the com-
position can vary from about 2 to about 6 weight percent
of the total composition. Pr~ferably, th~ acrylate co-
polymer is present in amounts of from about 3 to about
5 wPight percent of the total compositionr
; The amount of the ole~in-ac~ylate copolymer present
in ~he composition of the present invention can range from
about 0~5 ~o about 2 parts, by weight percent of the total
` composition, preferably about 0.75 to about 1.5 weigh~
percent~ T~e ~emainder o~ the composition is aromatic
4 8CL-6041
~6--
carbonate polymer. The term "total composition" is the
sum of all the polymeric constituents of the composition.
It is also regarded to be among the ~eatures of this
invention to include in the composition of the invention
conventlonal addit.ives for purposes such as reinforcing,
coloring or stabilizing the composition in conventional
amounts.
The compositions of the invention are prepared by
mec~anically bl~nd; ng the high molecular weight aromatic
polycarbonate ~ith the butadiene-styrene copol~mer and
the acrylate polymer by conventional methods. Double
or twin screw extrusion is preferred, particularly where
additives are add~d to the composition.
EX~MPLES
15 ~ The ~ollowing examples are set forth to illustrate
~he invention and is not to be construed to limit the
scope of the invention. All percentages are on a weight
basis unless otherwise specifiedO
EXAMPLE 1
Eighty-six (86) parts of an aromatic polycarbonate,
'~ derived from 2,2-b.is(4-hydroxyphenyl) propane and having
an intrinsic viscosity (I.V.~ in the range of from about
0.46 t.o about 0.49 dl/g as determine~ in methylene chlo~ide
', solution at 25C, was mixed with three~3) ~arts o~ a co~
25 ' polymer of n-butyl acrylate and methyl methacrylate (here
inafter acrylate copolymer~, said copol~mer having a
wQight ratio of n-butyl-acrylate ~o methyl methacrylate
of about 3 to 2; one (1) part of an olefin acrylate co-
polymer having a weight ratio of ethylene~ethyl acrylate
of 4.5:1; ten parts of a butadiene-styrene copolymer
. ~hereinafter referred to as BDS~, said copolymer having
: a weight xatio of styrene to buta~iene of from abou~ 2 to
1 to abou~ 3 to 1. The in5redients were then ~lended
. together by mechanically mixing them in a laboratGry tumbler
and the resulting mixture was fed to an extxuder which was
8CL-6041
--7~
operated at about 255C. The resulting extrudate was
comminuted into pellets. The pellets were injection
molded at about 250C to 270 C into tes~ specimens of
about 5" by 1~2" by 1/4" and 5" by 1/2" by 1/8", the
latter dimension being the specimen thickness. Izod
impact strengths of these specimens are measured according
to the Notched Izod test, AST~ D256, and are set forth
in Table I. The superscript refers to the per~ent
. ducility at the oot lb. value. The sample labeled CONTROL
10, was a bisphenol-A polyarbonate having an I.V. from a~out
O.46 to a~out 0.49 dl/g. No other polymers were present
in the control.
EXP~IPLES 2-5
. Further samples of the composition of the invention
15 . were prepared as in Example 1 each cont~in;~g he same
kind and quantity of acrylate copol~ner and olefin
acrylate copolymer as in Example 1, (3% and 1~ respecti.vely).
However, the amount of BDS was increased i~ each samp~e
, to 15~, 20%~ 25%, and 30~ respectively. Each increase
2Q in BDS concentration brought about a concomitant decrease
in aromatic polycarbonate concentra~ion. The samples
were tested as in Exam~le 1. Belo~ ~re ~.he .~esu~.ts for
the impact te~t.
'TABLE 1
EX~MPL~ BDS WT.~ N~ P:~ IZOD, ft-lb/in.
j lJ8 inch 1/4 inch
ContrGl -- 14.81 1 6
. 1 10 ' 14.71 11.11
13.41~ ~0 4100
3Q 3 20 ~ 13~41 9 91~0
4 25 ~1v4100 9 1100
11.4 9.7
!
j;
~ O ~ 4 8CL-60~1
The results demonstrate that the impact strength of the
new composition is substantially retained in comparison
to the control with respect to the 1/8 u samples . The
impact strengtlls are su~stantially improved in the 1/4 "
samples. Processability of the novel composition is
significantly improved over the co~trol.
