Note: Descriptions are shown in the official language in which they were submitted.
W0 91/155q5 ~ 75~ P~ rtVS9~ 347
~ i r
'HIGH IMPACT POLYETHYLENE ~E~EPHTHALATE-POLYCAR~ONATE
~L~ND COMPOSI~IONS
BACKG~Q~D
Ls~l-Fi~l~ of ~h~ Inven~,ion:
The present invention relates to par~icular
polyester molding compositions which are characterized
by e~ceptional toughness subsequent to ann~aling. More
particularly, the pr~sent invention is direct~d towards
a composition which comprises a polyester and
. polycarbonate or a polyarylate whlch further includes 3
reactive impact modifier.
2. Des~ip~ hQ_~LL~
Engineered plastics enjoy widespread popularity
for the production of articles through the use of
molding or casting processes. The ma~erials typically
comprise one or more polymeric materials which e~hibit
specific properties, i.e., toughne~s, rigidity,
chemical resistanc~, long-~erm hygrothermal ~imensio~al
stability, dielectric stren~th, and the like.
Frequently, ma~erials which e~hibit particular features
such as thos~ listed are utilized as constitutents in
the formation of so call~d ~blended polymers~ which
comprise two or mor~ constituen~ materials, such as a
two or,more polym2rs, or a polym~r with a non-polyme~ic
25 material,- which eoalstitut~nts will ideally form a
material which ~hibits the beneficial feature~ of ~he
con titu~nts, wikh f@w if any dekximental quali~ies.
Unfortunat~ly, a~ is well known to the art, the
formation o~ blended polymeric ma~eri~ls ar~ rarely
30 atta ned whioh offer the d~irabl~ ch~ract2ristics of
the constituerlts, without simultan~ously suf~ering f r~lm
some d~trimen~al quality.
One polymer which is widE31y used in the
formulation of en~ineer~d plastics is a polymer of ~n
35 arosn~tic carbona'ce. Such carbonate polyrn~rs, also
generi~:ally term~d in the art as ~PC's", may rsadily be
W~ 9!/155q5 ~ ?~ b ; ~ ; P~/US91/~3~7
759~ 2~
prepared by reacting a dlhydri~ phenol, ~uch as
2,2-bis-(4-hydro~yphenyl)propane with a carbonate
precursor, such as a phosgene, in the presence o~ an
acid binding agent. Generally, aromatic polycarbonate
plastics may be easily molded, hal~e a hiyh tensile and
impa~t strength, and e~hibit an e~cellent d~gree o~
dimensional stability in most articl~s formed
there~rom. However, in particular applications,
aromatic poly~arbonates are unsuitable as they ar~ also
known to e~hibit se~ere environmental str~ss crazing
and cracking, i.e., a type of failure which is ~nhanced
by the presence of organic solvents such as basic
solvents su~h as many hydrocarbons, alcohol~, ketone~,
etc which are the constituents of may common automobile
fluids, ~asoline, paints, and th~ like. Most
significantly, the loss of impact str~ngth a~d an
increase in brittle type failures in standard testing
procedures has been obser~ed. C~rtain formulations of
polycarbonates have been devised which increase the
resistan~e of poly~arbonates to envlronmental stress
cracking including the a~dition of a minor amount of a
polyalkylene terephthalate ~uch as poly(ethylene
terephth~late) and polySbutylene t~rephthalate).
~ -~How~Yer, arti~les formed from a blend of a -
polycarbon~te a~d a minor amoun~ of a polyalkylene
terephkh~l~te haYe been observed t~ h~ve a lower impact
r~ tan~e to that of the polycarbonate itself. This
ha~ l~d to the suggestion of using additional
co~titu~t~ in a poly~arbonate and poly~lkyle~e
~ereph h~ bl~nd in order ~o im~rove th~ impact
r~ tanc~ o~ ~uch ~aterials.
Polyalkylene t~rephthalates including
poly(ethylen~ tereph~halate), al~o k~own to the art
by its at:ronym "P~T~, and poly~butylene t~r~phthalate),
35 similarly referred to as "P~T" are aromatic polye3~rs
which ~njoy Fr~que~t us~ either as tlh~ sole materials
or as consti tuent~ in plastic produc~ wh~re rigidi ty,
WO 9 1 / 1 5~45 . r ~; PCT/ US91/0l347
~ ~3~ 2~ 5~
impact resistance, and,,,~rasion resistance, are
required. This is kno~n to the art to be due ~o the
relatively high degree ~ crystal1inity which
polyalkyle~e terephthalates, particularly P~T, ezhibit
subseguent to cooling fromthe melt, a~d thus encourages
~their use in many molding op~rations, particularly
~njection molding processes. Ho~ever, these ma~erials
most particularly PET, are known to e~hibit poor impact
resistance properties subsequent to anneali~g or h~at
aging. In contrast to PBT, injec~ion molding of PET
results in a slow rate of crystallization and
non-uni~orm or low crystallinity in molded articles.
Subsequent annealing or h~at e~posure of PET molded
articl~s caus~s further crystalliza~ion resulti~g in
larger, non-uniform crystalline structures. Howsver,
as is well known to the art, polymers which e~hibit
large, non-uni~orm crys~alline struc~ur~s also e~hibit
low impact re~i~tance, a quality which is frequently
unde~irable in mold~d article~. Thu~, unfilled PET is
not normally preferr~d a~ injection molding resins due
to its low~r impact re~istanc~ as compared to P~T,
after crystallization.
Further ~uggestQd improveme~t~ in the processing
and khe phy~ical propertie~ of p:la~tic ma~erials
comprising a bl~nd or mi~tur~ o a polycarbona~e and an
poly(alkyl~ne t2r~ph halate) h~v~ iM~luded the addi~ion
of furth~r constitu~nts to the~e two polymer~, or ~he
u~ o ~p~cific molding proce~ es Eor ~he production o
ar~icl~ form~d from polycarbona~ and poly~al~ylene
t~r~phth~l~te) bl~d3. So~ ~ample~ iaclude U.S.
Pat~nt 4,522,979 to Chung ~t.al. or nMolding
Compo~ition~ Having An E~hanc~d R~ t~nce to Gasoline"
which disclo~e~ PE and PC bl~nded ~i~h rubbery impact
modified ~d a blocked polyi~ocy~nate prepolym~r, U.5.
P~tent 4,769~556 to ~u~b~rg et.al. ~or WT~rmoplastic
Moldinq ~terial~ of Polye$t~r and Polycar~onate~
- - disclo~ing a th~rmopl~ti~ mold.ing m~t~r~al ~ompri~ing
~ q _
polyalkylono torephthalat9~, polycarbonat~ and a
rubb~r toughon~r and rubb~ry ethylene copolym~r~, U.S.
Pat~nt 4,~97,44a for "polye~ter/polycarbonate Blends~
to Romanc~ for PE/PC ble~d~ ~hich include core shell
S rubb~s as impac~ modifiersi U.S. Patent 4,737,5~5 to
Liu et.al. for "Ternary Polycarbonat~ ~lend~
disclosing compo~ition~ having a major amount of an
aromatic carbonatc polymer, and a minor amount o~ an
aromatic carbonate polym~r impact modifying composition
co~pri~ing a ~teleblock~ copolym~r o~-a vinyl aromatic
compound and an ol~finic ela~tom~r, and an ol~in
alkylacrylate. Furth~r ar~ U.S. Patent 4,S29,76Q to
~iu ot.al. for ~Compo~i~ion o~ Polycarbonat~,
Polyc~ter, Acrylat~ Ela~tom~ric Copolym~r and a Pheno~y
15 Re~in~ di~cus~e~ a polymer compo~1tion which comyrises
a PC, polyalkylene terephthalat0 and an ela~tomeric
acrylat~ co~olym~r, and of particular not~ is U.S.
Pat~nt 4,753,980 to D~yru~ for ~Toughsned Thermoplastic
PO1YQ~ter Compo~ition~ wh~r~ Deyrup d~3cribe~
compo~ition~ which includ~ a poly~t~r re~ln, which may
- b~ a poly(alkylene ter~pbth~lat~ polym~r, ~uch a~ PET
or poly(butyl*n~ t~rephthalat~, which i3 commonly
known as ~P~T~ ~ith~r a~ a homopolym~ or a copolymer,
or mi~t~ of PET and P~T, and an 0thyl~n~ te~polymer
such a~ ~thyl~n~Jm~th~c~ylat~/glycid~l m~thacrylat~.
Purth~r, Europ~n A~ atlon 0 180 648 to Toray
- Indu~t~o~0 Inc. fot a "Poly~t~r Compo~itio~ and
~ol~ng~ Th~r~of~ di3010~ a polyme~ compo~ition
com~ g ~ aromatic poly~st~r, an aro~atic
polyc~bon~t~ ha~ing a numb~r av~rag~ rnol~cular weight
o~ lo,ooo to ao,ooo and a oopolym~r consi3ting
e~ ti~lly of an al~ha~ol~i~ and th~ gly~dyl es~er
o an alpha,b~t~-ehylenlcally u~a~ura~d car~o~ylic
acid.
T~ r~
.~
Additionally~ European Application 0 ~06 267 to
BASF AG describes impact modi~ied polyester-
polycarbonate composition~ containing polyethyl~ne
tereph~halate, an aromatic polycarbonate, and ~
ethylene/n-butyl acrylate/glycidyl methacrylatQ
terpolymer.
While some of these technique~ have provided
co~positions yielding articles havlng satisfactory
properti2~, their diversity and number
a r~
~i
7~
WO91/1~4~ Pcr/us9l/ol347
~ 5
indi~ate that the n~ed fo~ novel
compositions which e~hibit further i~proYem~nts in
properties, and processability
e:~i s~s .
In accordance with the instant in~ention there
is provided an impact modified polyester-polycarbonate
composition comprising:
a polyester,
a polycarbonate represented by re~urring
structural units o~ ~h~ formula:
-[-A-O-C-O-3-
where A is a divalent aromatic radical de~ived from a
dihydric aromatic compound, and a reac~ive terpolymer
constituent (hereina~ter interchan~0~bly referred to as
~graft terpolymer~) which comprises a compound having
the formula:
[Formula l] E/A/~
where W~ is.repr~entative of an alpha-olefin, or in
the altern~tive, an alkadiene, ~A~ i~ r~presenta~ive
of a mat~rial ha~ing the formula,
[Formula 3] C~2 ~ C
z
where ~Y~ is -H or an alkyl substituent~ ~Z~ is -COOR,
-CN, -OCOR, or ~Ar, wh~rein "R~ may be a me~hyl, e~hyl,
butyl or other alkyl group, and ~r~ may b~ a phenyl or
q ~ 5 ~O91/15~45 ~ i ~ - P~T/US~1/01~7
-6-
substitued phenyl, and "X~ repr~sent~ a comono~er
e~hibiting th~ structure
[Formula 4] CH2 _ C
, -
which contains a r~aotive functionality ~P" which is
selected from epo~ide, isocya~ate, 1,3-o~azoline, or
acyllactam ~unctio~alities, where the ~erpolymer forms
graft linked bonds with other polymerie materials in a
composition, particularly with polycarbonates an~ the
poly(ethylene terephthalates).
Molded articles comprising the .inventive
composition are also provided.
It ha~ al50 been unespectedly discoY~red that a
polymer composition having impro~ed properties may be
produced wherein the inv~ntive polymer composition
comprises a polycarbonate and a poly(ethylene
terephthalate) and an actiYe yraft terpolymer ac~ording
to the afor~m~ntioned formula ~E/A/X~ which graft
terpolymer eshibit~ th~ reactiv~ ability of forming
graft-type bond~ wi~h poly~arbonat~s and with the
terminal group~ of poly(ethyl~ne tersphthalate)
exhibits impro~d properties, especially retention of
high impact r~is~ance properties 3ubs~qu~nt ~ h~at
a~in~.
A~cording to th~ pr~ent in~ntion, the polycarbona~es
30 whi~h ~y be u~ed ar2 the carbvnat~ pol~rs of
dihydric ph~nols. Such poly~arbona~2s m~y be prepared
by r~acting a dihyd~ic phenol with a 02rbonat~
precur~or such a~ a pho~gene, a halo form~t~, or a
carbon~t~ ~t~r. In g~neral, the r~ulting
WO91/15545 ~ 2 ~ ~S 9~ O Pc~/us9l/ol~7
polycarbonate may be represented by recurring
structural uni~s of the formula:
.
[Formula 2] 0
..
-[-A-O-C-O-]-
where A is a diYalent aromatic radical derived f rom a
dihydric aro~atic compou~d, preferably ~isphenol A.
These dihydro~y aromatic compounds are defined as 4,4~-
dihydro~ydi(mononucl~ar aryl)A compounds ~h~e th~
mononuclear aryl may be ph~nyl, tolyl, ~ylyl,
ethylphenyl, isopropylphenyl~ etc., and the con~ecting
A groups may be -CH2-, -C2H~ C3H6,
-C H8-, -52-' -S-, -O-~ C3F
Typical dihydric phenols are
2,2-bis(4-hydro~yphenyl)propane
2,2-bis(4 hydro~yphenyl~ h~af luoropropane;
2,2-bis(4-hydro~yphenyl~pe~tane;
2,4'-(dihydro~ydiphenyl~m~thane;
bis-(4-hydro~yph~nyl3methane;
bi~-(2-hydro~yphenyl)m~thane;
hydroquino~e; .
Resorcinol;~
2S bis-(4-hydro~y-5-nltrophenyl)methane;
1,1-bis~4-hydro~yph~nyl~e~hane;
3,3-bi~(4 hydrs~yphenyl)pentane;
2,2~dihydro~ydiph2ayl;
2,6 dihydro~y~a~thalen¢;.
~bis-(4-h~dro~ydiph~nyl3sulfo~e;
bis-(3,5-diethyl~4-hydro~yphenyl~sulfon~;
2,2-bis (3,$-dim~ hyl-4-hydrosyphenyl~propane;
2,4~-dihydro~ydiph~nyl ~ul~one;
5'-chlvro-Z,4'-dihydro~ydiph~nyl sulfone,
bi3~ hydro~yph~yl~diph~yl sulfone;
4,4~dihydro~ydiph~1 e~her;
4,4'-dihydro~y-3,3'-dichlorodiphenrl ~theri
W~91/lS~S.; ,~ P~ 91/013~7
~7 5 ~
~,4'-dihydroxy-2,5'-dihydro~ydiphenyl ether, and the
like.
Other suitable dihydric phenols are disclosed in
U.S. Pa~ents 4,126,602, 2,999,835, 3,02B,365,
3,~34,154, and 4,131,575. It is also possible to
employ two or:mor~ different dihydric phenols for the
preparation of the polycarbonate.
These aromatic polycarbonates can be manu~acture
by known processes, such as noted above, by reacting a
dihydric phenol wîth a carbonate pr~cursor, such as a
phosgene with the methods set forth, and disclosed in
U.S. Patent 4,018,750, or by transesterification
processes disclo~d in U.S. Patent 3,153,008, as ~ell
as other process~s well kno~n to the ar~.
Further, as noted above, two or more differ2nt
dihydric phenols may be utilized, as well as a
copolym~r of a dihydric phenol with a glycol or with a
hydro~y or arid-t~rmina~ed polyester or with a diba~ic
acid in the eve~t a carbonate copolym2r rather than a
homopolymer is desire fox u~ in the preparation of ~he
polycarbonat~. ~ranched polycarbonates are also
useful, such as tho~ described in U.S. Pat nt
4,001,184. Furth~r, blend~ of a linear polycarbonate
and a branch~d polycarbonate m~y al~o be u~ed:
Moreover, bl~nd~ of any of the above materials may be
employed in the pr~etio~ of this in~ntion to pro~ide
th~ arom~tic polycarbonate. In any ~ent, th2
pr~f~rr~d aromatic polycarbo~ate~ are those select2d
from th~ group con~is~i~g o:
30 poly(2,2-bi~(4-hydro~ypehyl)alkane3 carbonates. The
mos~ pre~err~d O~. ~he~e polycarbona~es is a
polycarbonate deriv~d from
2,2-bis(4-hydro~yph~nyl3propane.
PolycDrbon~t~s utilizabl~ with th~ invention
~ho~ld h~ve a ~umb~r-aY~rage ~olecular ~eig~t of 10,000
to 80,000. Pr~ra~ly, th2 ranqe of the ~umber-av~rage
molecular ~ight is in the range of 15,000 to 40,000.
W~91/15~5 2~ PCT/VS9~/~33q7
_9_
Whil~ the specific number-av~rage molecular weigh~ of
the polycarbonate is recognized not to be detrim~ntal
to the operation of the novel graft terpol~n~r which
provides i~proved properties in polymer compositions
within which it is utilized, it has be~n obser~ed that
when the number-average molecular weight of the
polycarbonate is less than about 10,000 or more than
about 80,000, the resultant product polymer composition
has been observed to be inferior in molding and
processability, or deficient in mechanical prop~rties,
particularly tensile strength subsequent to heat agi~g.
. The polycarbonates should preferably e~hibit an
intrin~ic or inherent viscosity of about 0.2 to 1~2
dl/g, (deciliters/~ram) more preferably of about 0.~ to
0.9 dl/g in dichlor~methane by standard Ubbehlohde
viscometry a~ room temperature, Although not
essential, the polycarbonates should preferably contain
hydro~yl end groups.
Suitable polye~ters include polym~rs which
e~hibit an inherent visc03ity of 0.3 dl/g or greater
and which generally are the linear saturat~d
condensation products o gly~ols and dicarbo~ylic
acids, or reactive derivate~ th~r~of. Pre~rably, ~hey
will compri~e cond~n~tion products of aromatic
dicarbo2ylic acid~ h~ing a to 14 carbon atoms and at
least one glycol ~ cted rom the group consistin~ of
cycloh~ne dim~thanol, neop~ntyl glycol, and alipha~ic
glycols of the formula HO(CH2)nOH where th2 letter
~n~ m~y b~ ~ny i~t~ger of 2 to l0. Up to 5V mole
p~rc~At o the aroma~ic dicarbo~ylic acids can be
r~pl~c~d by at lea~t one diff~rent aromatic
dicarbosyli~ acad having from 8 to l9 carbon atoms,
and~or up to 20 mol~ p~rc~nt can be r~placed by an
aliphatic dicarbo~rlic acid haYing from 2 to 12 car~on
atoms.
In accorda~ with th~ pre~nt in~2ntion,
suitable poly~s~er~ include:
W091/15~45 `~ 5 9~ 1 o- PCrtUS93/013~
poly(ethylene terephthalate);
polytl,4-butylene)terephthalate;
1,4-cyclohe~ylene dimethylene
terephthalate/isophthalate copolymer and other linear
S homopolymer esters derived from aromatic dicarbo~ylic
acids, including but not limited to isophthalic, ~ ,
bibenzoic, naphthalene-dicarbo~ylic including
1,5-naphthalenedicarbo~ylic acid;
: 2,6-naphthalenedicarbo~ylic acid;
2,7-naphthalenedicarbo~ylic acid;
-~ 4,4'-diphenylenedicarbo~ylic acid;
bis(p-carboxyphenyl)methane;
1,4-tetramethylene bis(p-02ybenzoic~ acid;
ethylen~ bis~p-o~ybenzoic) acid;
ethylene bis-p-benzoic acid;
1,3-trimethylene bis(p-o~ybenzoid)acid; and
1,4-tetramethylene bis~p-o~ybenzoic) acid;
and glycols sele~ted from but not limited to
2,2-dim~thyl-1,3-propan~ diol;
20 neopeDtyl glycol;
cyclohe~ane dimethanol and
aliphatic glycols of the general formula HO~CH2)nO~
where ~ may be an int~yer from to 10, and thereby,
for e~ample and not by~-limitation, may be one of the
- 25 following:
ethylene gly~ol;
1,3-trim~thyl~ne glycol;
1,4~te~ram~thylen~ glycol;
1,6-h~ htyl~n~ glycol;
1,8-o6ta~th~1ene ylycol;
l,10-d~cam~thylene glycol;
1,3-propyl~e glycol; and
1,4-butylene gly~ol. Vp to 20 mole percent~ as
indicated abo~e, or one or more aliphatic a~id may be
included. For e~mple, suitable alipha~ic acids
include adipic, ~b~ic, azzelaic, dod~andioic and
1,4 eycloh~n~dic~rbo3ylic.
W0 91/15545 ~ , YC'I/lJS91/013q7
Prefereably, the polyester is one or morE~ o~ the
poly(alkylene terephthalates), either as a ho~opolymer
or as a copolymer of two or more poly(alkylene
terephthalates). The acronym "PAT~ will b~
S - interchangeably used as a designator for poly(alkylene
terephthalates) as a labelling convention herein. I
The pr2ferred compositions include PET
homopolymers, or PET copolymers ~ontaining minor
~ amounts of comonomers, as distinct from-PBT
-homopolymers as as is well known to the art, these two
materials e3hibit different morphologies due to the
differences in their crystallization behavior. This
difference, viz. the lower crystallization rate and th~
tend~n~y to form large, non-uniform crystalline
structures in the case of PET as compared to PBT, in
finished arti~les is known to the art to account for
the different impact stren~ths of these materials
subsequent to an ann2aling operation, or subsequent to
any e~tended e~posure to heat . PET' s relatively rigid
non-uniform crystalline morphology is known to cause
more brittlene~s, and is thus le~ de~irable as a
material or use in forming articles, particularly in
the absence of ~ rs and reinEorcing agents.
~ The;polyester should preferably have an
intrinsic vi cosity of about 0.2 dl/g to about 1.2
dl/9; mor~ preferably the viscosity ~hould be in the
range of b~tween about 0.4 ~o about 0.95 dl~g. ~h~s~
vi~osi~y values are determined wi~h the use of a
3tandard Ubbehlohd~ com~ter in a
30 ph~nol-t~trachloroethane ( 6a/40 v/v) solution in a
cor~c~ntr~tion of O . 5~ at room temp~rature . The
poly~t~r~ ~hould preerably have active chain ~nd
groups viz., carbo:cylic acid and~or hydro:cyl snd qroups
in a conc~ntration of at least 0.01 m~q/~. The end
35 groups are determin~d by s~c~nclard til:rametric met31ods
or carbo~yl or hydro~yl determinat.ion.
WO91/155~5~ ' -` ` PCr/~S9~/01347
2~ 12- '
The compositions in accordance with the present
invention, based on the total weight percentage of the
compo~ition, includes relative weight ratios of the
polycarbonate in the range of about 30 to about 60
percent; the polye~ter in the range of about 30 to
about 60 percent; and the graft terpolym~r more fully
discussed below in a range of weight ratios of between
about 2 and about 30 percent. ~ore preferably the
polyester should comprise about 40 percent of th~
10 composition, with the polycarbonate and the graft
terpolymer comprising the remaining amount of the
composition, as it has been observed that favorable
impact properti~s sub~equent to heat aging haYe has not
been realized where the polyester is present in less
than such a proportion.
According to the inve~tion, the compositio~s
will further include a terpolymer constituen~, or as
interchangeably ref~ren~ed above, a ~graft terpolymer"
comprising a compound having the formula:
~Formula 1] E/~/X
where ~E~ is r0pre~entative of an alpha-olefin, or in
the alternative, an alkadiene, WA~ is representative
of a material having the ormula,
[~ormula 3~ C~12 ~ C /
wh~re ~yl is -H or an alkyl substitu~nt, ~ZA is -COOR,
~CM, -OCOR, or -Ar, of which "Rn may bP a methyl,
ethyl, butyl or other alkyl group, and ~Ar~ may be a
WO 9l/155qS ., ? ~ ; PC'r/US9~ 1,3~17
3-- ¦
phenyl or substitued phenyl, and r'XA represents a
comonomer e~hibiting the structure
S [Formula 4] - CH2 , C
,. ~ p
which contains a reactive function P" which is
selected from epo~ide, isocy~,nate, 1,3-o~azoline, or
acyllactam funetionalities. Typically, nxn has a
moiety derived from acrylic and methacrylic acid or
allyl alcohol, e.g., glycidyl acrylates, glycidyl
methacrylates, or glycidyl allyl eth~r. ~he terpolymer
~orms graft type bn~ds with other polymeric materials
in a composition, particularly with polycarbonates and
the poly(~thyle~e t~rephthalates).
In accordanc~ with the in~ention, the
constitu~nts of ~ are epo~ide, isocyana~e, acyllactam
or o~azoline. Accordingly, ~ having epo~ide
functio~aIities may be derived from glycidyl acryla~e,
glycidyl methcrylate, gly~idyl allyl ether, asld other
glycidyl contal~ing compounds. W~ere ~ is ~o have an
isocyan~te unctionality, ~ may be~derived from
2-isocyanoto~thylmethacrylat~, p-isoprop~nyl
alpha,alpha-dimethyl benzrl iso~yana~e, m-isoprop~nyl
alpha,alpha-di~thyl benzyl i~ocyanat~) and ths like.
Wher~ ozazoline functionalities are d~sir2d, 2 may ~e
d~riv~d from 2-i~oprop~nyl~1~3~o~azoline, 2-(p-~inyl
phenyl)-1,3-o~azoline, and the lik0. Wh~re acyllac~a~
function~ligy i~ de~ired, ~ may ~'i2 deri~ed rom
metha~ryloyl c~,prolactam, m~thacryloyllaurolactam,
compounds of th~ g~neral form~la:
[Formula 51 ~2 ~ C ~
\ CO~ - CO
~ (C}12 ))
WO9l/15545 ' . G r .~ ~ PCr/ ~S9 1 /~ 13
where "~ may have a value of ~ to 10, and ~y~ may b~
-H or -CH3~
The grafted terpolymer may be synthesiz~d by
copolymerization o~ E, A or X in bulk or solution
phase, catalyzed by free radical initia~ors or other
types of i~itiators. The relative weight ratios of the
constituents comprising the graft terpolymer may be
.present in p.roportions which, relativ~ to the total
~,~weight of the terpolymer of between about 98.9 and 45
weight. percent E, hetween about 1 and 40 weight percen~
A, and between about 0.1 and about 15 wcight percent
X. It is to ~e noted that the relative proportions of
the co~stituents relative to the total weight are
subject to a gr~at deal of variation and are dependent
upon the w~ight of the individual constituents.
Further, their relative proportions may be adjus~ed ~o
suit the reactivity of a particular composition.
All of these functional groups of the terpolymer
disclosed in this inYention are found to eshibit
2n graft~ng with the PET and the PC due ~o ~heir high
r~activity; E/A/~ ~ompositions where X e~hibits an
epo~ide or oxazoline functionality were found to be
highly ad~antageous.
. An.ad~antag~ouq feature of-the t~rpolyrner is
that the "X~ ~un~tion~lities also act as ~water
scaveng~rs~ within the pol~mer~ and during the
production o th~ polymer may act to remove free wa~er
molecule~ from the polym~r melt. Such a feature
eliminate~ th~ ~c~sity of dryi~g the poly~ethylene
ter~phthalate) before it is melt~d during processing,
which.is a f~ture e~p~cially advantageous when
recycled PET i~ u~d as a ~eedstock. This is
beneficial in forming polymer compositions which have
lower w~ter contents, and hence, require less or no
35 ~ryin9
It should ba ~vident to those s~illed in -thP art
that minor amounts of organic modiFier~, gen2rally to
WO91/15545 ~ ~ ~59~ cr/us~l/0]3~7
-15-
comprise no mor~ than about 10% of a composition, may
be added to the composition according to the
invention. E~amples of such typical modifiers include
heat stabilizers, flame retardants, pigm~nts and
; coloring agents, nuclea~ors, lubricants and ~low
modifiers, especially ethylen~ copolymèrs which are
frequently used additives for improving the melt
flowcharaotsristics of many polymer ~aterials. Also,
the use of in-organic materials as in-organic
modifiers, such as fillers, and reinforcing agents
(including qlass fibers, talc carbon fibers, and th~
like~ may be includ~d in any suitablP amount, which is
preferably in a range typically used in the art,
between about 40 and 50%.
The compositions in ~he E~amples were generally
prepared by one of two methods. In the first method,
where there is ~o preblending of the components, the
melt blend is pr~p~r~d by first dry blending the
constituents in their appropriate weight percen~ages by
tumble blending or in a rotary drum, then feeding in
the blended constituents into the hopper o~ a single
screw e~truder which was heated so to form a melt of
the-co~stituents and th~n e~truding it through a die to
form strands; The e~trudate was rapidly pa~sed through
a water bath in ord~r to quenoh and cool tAe strands.
TA~ stra~d~ wsr~ th~n pas~ed through a pell~izing
m~chine and the p~llets w~r~ collectsd and dried.
- In the 3~cond method ~Jh~re an additional
pr~ ndi~g 3tep i~ includ~d in th~ ~ormation process,
th~ polyc~rbon~t~ utilized and th~ terpolymer are firs~
prebleQd~d beore combinlng th2m with the PET of any
d~sired compo~ition. Thi~ s~cond method is the
pre~rr~d on~ as the pr~bl~nding allo~s for a mo.re
homogen~ou~ pha~ distribution of th~ t~rpoly~er and
~he polycarbon~te~ ~hich b~ing pr2bl~nded, impro~es t~2
distribution of the terpolymer within th2 poly~arbonat~
and PET, incr@~ing the amount of grafting in ~he ~inal
W091/15545~ 16- P~r/us91Jol~7
composltion and thereby enhancing the improYed
properties of the final composition. Accor~ing to ~his
second method, the polycarbonate and the t2rmpolymer
are first preblended via a melt e~trusion before
blending with the PET by another melt extrusion
operation, thus essentially constituting a 2~step
single screw extrusion process. Alternatively, the
melt blend may be prepared by use of a 2-stage, single
pass e~rusion process. In such a process, a dry blend
o the polycarbonate and the terpolymer in their
appropriate weight percentages is introduced into a
first hopper of a single screw e~truder. The
appropriate amount of PET is introduce into a second
hopper of the estruder at location downstream
approximately midway between the first hopp~r and the
die at the e~it of the e~truder. Similarly, the
e~trudate was rapidly passed through a water bath in
order to quench and cool the strands which were then
pelletized, and collected, and when nec~ssary, dried.
The pellet~ were utilized to mold te~t specimens
which were 1/8 inch test bars which are a standardized
sample size well known to the art by use of an
injection molding machine. ~oth tensile bars and Izod
impact bars wer~ prepar~d utilizing this process.
. ,.. ~ .... , -, . . .
Subseguently, a quantity of the test bars wele annealed
in an ann~aling oven at a t~mp~ratur~ of about 150
deg.C wher~ they were retained for periods of either 16
hours or 72 hours in accordance with testing parameters
well k~own to the art.
~e3ting of ~he te~t bars was ~ccomplished in
accordance with the standardized testing
procedur~s pre~alent in the art; the tensile strength
was test~d in accordanre with
ASTM D-3029 sta~dards using a falling w2ight impact
tester, and th~ imp~ct str~ng~h
was de ermined under th~ ~esting condition~ o~ D-256
using a notshed Izod p~dulum
impact appara'eus ~or measuremerlt.
WO 91/15545 2~ 5~ ~ . PCT/US91/01~7
~';,l - 1 7 -
EXA~oeh~5_gF TH~ vE~IQ~ i
Th~ following examples show par~icular
embodiments of the pr2sent invention, and illustra~e
the e~traordinary touyhness properties of specific
S compositions of PET and polycarbonates by the incl~sio~
of a reactive terpolymer disclosed herein. It is ~o be
understood that the following e~amples of the invention
are for illustration only and the scope of the t
invention is bounded only by the accompanyi~g clai~s.
Unless otherwise indicated, the use of
percentages within any E~ample are to be understood as
the weight percentages of the indi~idual constitut~s
relative to the total weight of ~he constituents.
~am~
E~ample l is a melt blend composition consisting
essentially o~ 90~ PET, 40% of a polycarbonate and 20%
of an ethylene/~thyl acrylate/glycidyl methacrylate
terpolymer. The PET used w~s a bottle grad~ resin with
0.67 I.V. ( as determined in phenol/TCE) and typically
containing between about 0.035-0.04 me~/g of carbo~yl
chain ends. The polycarbonate used was commercially
available from the undcr the trade name ~Le~an", a name
used for a family of polycarbonate materials. The
. ~ particular polycarbo~ate us~d was ~Le~an lOl". The
ethylene/ethyl acryl2t~glycidyl ~erpolymer was
de~crib~d a~ h~ing a relati~e weight ra~io of 75
ethylene, 17~ ethyl acrylate and a~ glycidyl
func~io~ali~y.
The melt bl~d was prepared by first dry
bl~ndinq all of the constitu~nts toge~her and
subs~quently, the dry blended co~stituents were then
fed i~to the hopp~r of a ~illion l inch single scr~w
e~trud~r with a L/D ratio of 30~l using a f2ed scre~
equipped wlth a M~ddo~ mi~.ing head. The ~truder
barrel temperatur~ for each zone were kept at ~he
followi~g appro~imate ~empera~ur~s of: Zone l, 205
deg.C; Zo~e 2, 250 deg.C; Zvne 3, 27~ d0g.C; ~one 4,
WO91/15545 ~ ~ `'` -18- P~T/US91/0~3~7
250 deg.C. The te~perature of the flange waS kept at
appro~imately 250 deg.C and th~ temp~rature of the dies
was kept at approsimately 210 deg.C. The e~trude~
screw rotational sp~ed was maintained at about 60 rp~
The e~trudate was rapidly passed through a water bath
in order to quench and cool the strands. The cooled
strands were then passed through a pelletizinq maohine
and the pellets formed wer@ collected and dried.
Thereafter, the pellets were molded into test
specimens by injection molding using an injection
molding machine. The barrel temperature o~ the machine
during the injection process was maintained ~ithin a
temperature range o about 280 - 287 deg.C and the mold
was kept at a temperature of about 50 deg.C. During
the molding operation, the cycle time was appro~imately
10 seconds during the injection step, and appro~imately
20 second during cooling. The pressure of the
operation was approzimately 300 psi, with a pre~sure
hold of 500 psi. Standardized tensile bars and Izod
20 impact bars were pr~pared. A quantity of the test bars
were annealed, or heat aged in a circulating hot air
oven at about 150 deg.C for periods of either 16 hours
or 72 hours.
~ ~ T~ting of the samples included impact testin~,
tensile elongation, tensile modulus and yield stress
according to known t~sting proc~dures. ~he physical
propertie~ mea~ured indicate e~tr~ordinary toughness o~
th~ material sub~equent to annealing. Resul~s of the
ke~ts are summ~rized under the heading ~E~ on Ta~les
1 and 2 b~low.
The comparati~e e~amples A, ~, C, D and E are
composikioAs ~omprising P~T, PC and various impact
modifi~rs. Ea~h of these e~ample~ was prepared in the
same manner as kh~ cvmposition of ~zample 1, and
consi~t~d e~ ~ntially of 40~ PET, 40~ of a
polycarbo~ate and 20% of one of the various impact
modifiers.
~ ~a/15545 ;~ ~7~ 3 PCr/VS91/0~3~7
1 9--
Comparativ~ E~ample A used an m~thYl
methacrylate butadiene-styrene, (which is frequently
catergorized in the ~rt as a~ "interpolymer") or ~MBS~
core shell rubber as its impact modifier. This rubber
~njoys significant usage in the art as an impact
modifier as this material e~hibits good elasticity and
provides good impact absorption.
The impact modifier used in the composition of
Comparative E~ample ~ was an
acrylonitrile-butadiene-styrene, or "A~S~ rubbe~ which
similarly to M~S e~hibits good elasticity and good
impact absorption. The formulation B was comm~rcially
obtained from Mobay Chemical Co. under the trade
designation "Makroblend UT1018n.
The impact modifier used in comparative e~ample
C is an all-acrylate core shell rubber, which is
marketed under the trademark ~Paraloid KM 3~0" by Rohm
~ Haas, and consists of a cross linked
polybutylacrylate cor~ and polymethylmethacrylate
shell.
In the formulation of Comparati~e E:~ample D, an
ethyl/ethyl acetate copolymer ~as used as the irnpact
modif ier ~
Compa~atiYe Esample ~ utilizes an ethyl/glycidyl
me~hacryla~e copolymer as the impact modifi~r. The
particular copolymer is comm~rcial1y mar~eted under the
trad~name ~ondfast 2C~ and is aYailable rom the
Sumitomo Chemical Co. The relative weight ratios o~
the ethyl to th~ glycidyl m~thacrylate in the copolymer
is 94/60
The compositions of e~amples ~, B, C, D and E
were all produced, mold0d and subs2qu~ntly tested in
the manner utiliz~d in the productiorl of e3ample 1, so
to more cl~arly illustrat~ th~ distinct adYantage o
compositions made in accordance with the inYention~
Likewise, the testin~ o~ the samples included i.mp~ct
testing, t~nsile elongation, tensil2 modulus ~nd yield
2~7~9 ~
W091/155~5 ~ ? ~ 20- pcr/vs9l/ol3
stress according-to the same testing proc~dur~s
utilized in testing the composition of Esample 1. The
physical properties measured for these ComparatiYe
~xamples indicate the marked reduction in the toughness
S of the material subsequent to annealing, or heat aging
at 150 deg.C. R~sults o~ the tests are also summarized
under the appropriate headings and listed on Tables 1
:. and 2 below.
1 0 ~,~ ,,
_____________________________________
Example 1 A B C D
_________________________._____________
Notched Izod,
ft.lb/in: 14.9 12.4 12.5 13.3 13.1
-aged 16 hrs.:12.6 10 o O 10.1 9.2 2.5
-aged 72 hrs.:11.5 5.6 5.3 3.7 ---
Drop Weight
Impact
ft.lb: 97 ~ 156 --- ---
-aged 72 hrs.:~6 ---- 1.6 --- ---
- :- Te~s~
Elongation, ~: llS 128 113 95 97
-~ged 16 h~s.:85 40 30 18 33
-aged 72 hrs.:
T~n~
Modulu~, p~200,000 29~,000 270,000 ---~
-aged lS hrs.: 215,000270,000 29~,000 -~
Yield Stre~s,
psi: 5,400 6,160 6,~65 S,~20 2~2~0
-ag~d 16 hr~O 6,430 7,400 8,325 6,1~0 4,450
-aged 72 hr~.: 6,240 6,5lO 0,230 6,300 ~
W~91/1~545 , -21- PCT~US~]~3~7
TA~L~_~
__________.__________________________
E~a~ple: 1 E
______________ ___________
.
Notched Izod,
ft.lb/in: 14.9 1q.5
-aged 16 hrs.: 12.6 13.2
lO -aged 72 hrs.: 11.5 3.
Drop Weight
Impact
ft.lb: 97 ----
l; -aged 72 hrs.: 86 ----
Tensile
Elongation, s: 115 210
-ayed 16 hrs.: 85 125
20 -aged 72 hrs. : 67 7
The resultant physical test data particularly
illustrates that the compo~itions of the present
.ai invention, namely, the ~omposit:ions which include a
re3ctive graft-terpolymer show the une~pected
ad~antages of improved toughness subsequ~nt to
annealing and superior impact strength retention. This
is attributed to the functionality of the terpolymer in
lts ability to form a graft copol~mer throuyh reaction
with th~ terminal end groups, carbo~yl and hydro~yl, o~
PET and PC. Further, the e~cellent elasticity of the
terpolymer imparts good impact energy absorp~ion
qu~lities to the molded composition, and which is
furth~r b~ ed to act as a compatibilizing ayent for
the PET and PC u~d.
~a~
E~amples 2,3,4,5 and 6 are further embodim~ts
of the invention which utilized the constitu~nts as
WO91/1~545 PCT/~S91/0134~., ;
2~ ~ 3 ~ - 22-
used to formulate E~ample l, but varies the relativ~
proportions of the PET, PC and the reactive terpolYme{
used in E~a~ple 1. The range of variation for ~he
respective components based on the total weight o~ the
S composition ~as: 30% t~ 80% PET, 0~ to 50~ PC, and a
constant Z0% of the terpolymer. The speci~ic
proportions
are outlined in Table 3.
I~LE ~ 1,
_______________________________________________________ I
E~amples: Z 3 4 5 5
____________.__________________________________________
Constituent,
weight %
~.~~ ~D
PET: 80 60 50 40 30
PC: -- 20 30 40 50
E/EA/GMA
terpolymer: 20 20 20 20 20
The compositions of E~amples 2-6 were produced in the
same manner as that used ~or the production of E~ample
1.
. The physlcal charact~ristics-of the materlals
produced from the compositions outlined in Table ~ are
summarized in Table 4.
3S
WO 91/l5545 . 2 ~ 59~ ~ P~/US~1/111347
~, , ,. ., .-, , ,
TAELLE ~
______________.______ ___________________
E~cample: 2 3 4 5
:, ------------ ------------------ ---- -- ---- -------- -- :
. .
No t c:hed I æ od,
ft~.lb/in: 7.4 16.6 16.4 14.9 14.5
-aged 16 hrs .: 3 . 2 3 .1 5 . 7 lZ . 6 19 . l
lO -aged 72 hrs .: 3 . 2 --- 9 . 0 11 . 5 ---
Tens i le
Elongation, %: 2~g 165 127 115 72
-aged 16 hr~.: 23 29 41 85 100
15 -aged 72 hrs.: ~1 --- 25 67 ---
Tens i 1 e
ModulLIs, psi.: 5,400 5,400 5,523 5,980 6,380
-aged 16 hrs.
20 at 150 d~g.C: 6,390 6,000 6,400 6,640 6,770
-aged 72 hrs.
at 150 deg.C: 6,400 ~ 5,68~ 6,100 -----
T~nsi le
25 Modulus, p~ 18~, 000 183, 000 195, 000 200, 000
2~5, 000
-aged 16 hr~. :235,000 221,000 221,000 21~000
216, 0~
A~ ~118y b~ d~t~rmined rom Tabl~s3 and 4, the
compo~i~ion ~f ~:~a~Dpl~ 5 ~shibi~d
par~icula~ly good r~en~ion o impac~ properties and
elorlgation tr~ngSh.
E:ac~m~lo~ 7-12 e3~mplify th~ ~ec:o~d, alt~rnati~e
tn~thod o pr~paring the composition3. Accordin~ ~o
thi~ 3~::0nd m~'chod, an additional ~tep, apr~b1~ndirlq~
:
WO 91/1554S ~ . A'~ PCT/US9l/~1347
, ,, !, , ,,,`, ~,.' ';;
~75~?~ -2~
of the polycarbonate and the reactive terpolymer This
preblending may be ~c~omplished by methods known to the
art, including a two-step process, or a two-stage,
single pass e~trusion process. This latter process was
used for the formation of the compositions of E2ampl~s
7-12.
Table 5 indicates the various ratios of
constituents utilized in the compositions of E~amples
7-12 which were produced using a preblending step. The
percentages shown are percent by weight of the
composition of each E~ample.
T~L~ S
_______________________________________________._______
E~amples: 7 8 9 lO ll 12
_________________________________________________~_____
Constituent,
weight ~
PET: 40 40 45 50 50 60
PC: 40 45 35 30 33.3 2g
E/EA/GMA
terpolymer: 20 lS 20 20 16.7 16
Th~ corre~ponding physieal proper~ies observed
during th~ t~sting of thes~ materials is summarized on
Table 6.
WO 91/15~4S ~Cr/VS9~/nl3~7
-2S_ ~ S~
____________.. __________________~_________ ____________
Ea~:ample: 7 8 9 10 11 12
__________________________________________ ~____ ______
5 Notched Izod
-molded: lS . 816 . 816 . 518 . 717 . 518 . 8
-annealed,
16 hrs. a~
150 deg.C:14.~ 13.7 12.9 15.0 7.3 4.3
Ultimate
Elongation,
~6: 110 105 119 159 190 165
- anne a 1 ed ,
16 hrs. at
lS 150 deg.C: ~0 80 78 85 ~5 30
Ultimate
Tensi 1~
St rength,
psi: 5600 6~30 56~0 6060 6125 5880
-annealed,
16 hrs. at
. lS0. deg.C:64107445 613S 6580 6715 6100
- . ~ .. ii~, ,... ;, .. . .. . .
25 T~nsile
~o~ulus,
~1000'~)
p i.: 2D0 257 190 230 210 250
-ann~ d~
16 hrs. aé
lS0 d~g.C:2~0 2R0 210 ~60 2~0 ~67
~r~ 05Jln~O~a~rDr~/l lYII ~9~ C~ V/~V!~r8~/ll Y~lmO O~IJ~ ~I OV~ 0 113~1~D 51/ ~ ~l iD Cl ~11il 31 Q ~!III Q ~0 Q ~ D
As may be di3cerned rolT lth~ rssults shown on
Table 6, th~ co~positions show~d good retsntion of
35 impac:t str~ngth throus~hout, esp~cially ~or ;@~amples
7-10. It m~y ~urth~r b~ obs~rYed tha~ th~ ~cond
m~thod of forming c:ompositions, wh~re th~3r~ is
WC) 91/155415 ` PCr/VS()~/()13'17
J~
~ 2fi~ ~,
preblending may be ad~antageous to the f irst method
without preblending of the constitutents by a
comparison of the physical test data o Tabl~s Z and 3
with Tables 5 and 6 which contrasts similar
compositions produced by processes including no
preblending with processes including preblending.
Particularly, the following paired compositions having
th~ same ratio of constituents, arld their r~sultant
physical properties may be cumpared: E~ample 5 and
E~ample 7, E~ample 4 and 10. Particularly, the impact
test values (notched Izod) indi~ate improved
toughness~ Such results are believed to be
attributable to improved graftin~ of the reActive graft
terpolymer and the polycarbonate prior to the
lS introduction of the poly(ethylen~ terephthalate.)
E~amDle 13, CQmp~rativ~ ~am~
Th~ composition of E~ample 13 was a composition
consisting essentiall~ of 90~ PET, 40~ PC and 20
ethylene/ethyl acrylate/glycidyl methacrylate
terpolymer was produced. Comparativ~ Example E was a
composition of PET, PC and an
acrylonitrile-butadiene-styrene terpol~ner, which is
marked u~der the tradename nMakroblendn wa~ ~ested wi th
th~ composition of ~zample 11. ~oth compositions were
subjec~ed to drop weight imp~ct testing at low
temperatur~s (-40 d~.C) prior to, and subsequent to
heat agin~, and the results of thes~ tes~s is listed on
Table 7.
W(~ 91/155~1~ P~r/lJS~1iO~3~7
-27~ 5~, ~
X~,~ .. . ... . ..
E~ample: 13 E
_____________________________ _________________________
S ~rop weight irnpact
st rength a t
-40 deg.C.
(ft. lbs)
prior to heat
aging: 9~ . 7S 123 . 75
af ter heat aging
at 150 deg.C, for
72 hrs .119 . 64 3 . 24
_________ ____________________________._________________
The composition o E~cample 13 was no~ed to be
completely ductile b~fore h~at-aging, and the
composition of Comparati~e E~ample E was noted to be
20 completely brittl~ ater heat aging, and showed poor
strength reterltionO
Thr2e e~e~nplary composition~ comprising the
terpolym~r of the pre~nt in~ention by m~lt blendlllg
25 the constitu37lts in accordan~e with the me~hod
describ~d ~or ~E;3ample 1, with ~he f~llowing particular
compo~ition~ outlined on Table 8.
3~
WO 91/~15545 ~ t ~ PCT/US91/01347
r --2 El ~
_____________________________________________.____ ..._____
E~amples: 19 15 16
__ ___________.________________________~________________
Constituent,
weight %
ID W 1 11~ 8 31 IID il D ~111 --
PET: 40 40 40
PC: 40 40 qo
E/EA/GMA
terpolymer: 16 12 10
lS E/EA 4 8 10
copolymer
The following phy~ical prop~rti~ outlined o~
Table 8~ were obser~ed.
WO 91/355~5 . ,, PCr/US91~0~3~i7
-29- ~ J;~
______________________________..._______________________
E:~ampl~: 14 15 16
__~______
Notched Izod
-molded:16.2 16.2 15.8
- a nnea 1 ed ,
16 hrs. at
150 deg.C: 16.6 15.9 19.3
Ul t imate
Elongation,
%: 1~5 145 133
-annea led,
lS 16 hrs. at
150 deg . C:125 125 113
Ultimate
Tens i le
20 Stren~th,
psi: 6Z~ 65~5 62~0
-annea1ed,
16 hrs. at
150 deg.C 7900 7400 698q
Tensile
Pqo~ulu~,
~ 100~
p~ 21~ ~18 ---
3 -aQn~ d,
16 hr~. at
lS0 d~9~C: 245 250 ---
Th~ r~$ult~t l:~tirlg data re~reals thi3 t the
35 compo3itios~ on~ining an amolln~ of an ~hylene
copolymer, such ~ ~/~ not~d abo~?~, but not to b
limit~d G~ol~ly to E~EA, m~y b2 in::lu:led in
WO91/1~45 ~ P~/IJS91~U13~7
0-
compositions, generally in amounts of up to about 10%
so to replace up to about half of the reactive
terpolymer may be used without detracting from the
beneficial qualities of the present invention.
While these e~emplary embodiments have described
various aspects of the invention, it is to be
understood that the scope of the invention is to be
limited only by the following claims.
