Blends of polyetherimides and block poly(esteramides)

Blends of polyetherimides and block poly(esteramides) may contain about 99-1% by weight of the former and about 1-99% of the latter. Particularly useful are polyetherimides containing about 1-30% of the block poly(esteramide), which have improved impact strength and resistance to brittleness. The blends may also contain at least one poly(alkylene dicarboxylate) as a compatibility improver.

This invention relates to new resinous compositions of matter characterized 
by improved impact resistance and other advantageous properties. In its 
broadest sense, the invention includes resinous compositions comprising 
(A) about 99-1% by weight of at least one polyetherimide and (B) about 
1-99% of at least one block poly(esteramide) having the formula 
##STR1## 
wherein each R.sup.1 is independently a divalent aliphatic 
hydrocarbon-based radical, each R.sup.2 is independently a divalent 
aliphatic hydrocarbon-based radical, each R.sup.3 is independently a 
divalent aromatic hydrocarbon-based radical, and m and n are each at least 
about 100. 
Polyetherimide resins are well known in the art and are of considerable 
commercial value for use in molding compositions because of their good 
high-temperature characteristics and ductility. It has been found, 
however, that polyetherimides may become brittle under certain conditions, 
especially when subjected to a triaxial or highly strained stress state. 
Such a stress state is exemplified by the conditions of the Izod impact 
test as described in ASTM Procedure D256, Method A. In this test, the 
impact required to break a test specimen by striking it on a notched 
surface thereof is measured. 
It is, of course, desirable to formulate polyetherimide resins with as many 
advantageous properties as possible, including resistance to brittleness 
in the triaxial stress state. Accordingly, a principal object of the 
present invention is to provide resinous compositions with improved impact 
strength, resistance to brittleness and other advantageous properties. 
A further object is to provide improved polyetherimide resin compositions 
containing toughening ingredients. 
Other objects will in part be obvious and will in part appear hereinafter. 
As will be apparent from the foregoing brief description of the resinous 
compositions of this invention, they comprise two essential components. 
Component A, the principal component, is at least one polyetherimide. 
Polyetherimides are a class of polymeric materials well known in the art; 
illustrative disclosures of such polyetherimides and of methods for their 
preparation appear in a large number of U.S. patents, including the 
following which are specifically incorporated by reference herein. 
______________________________________ 
3,803,085 3,917,643 
4,092,297 
3,833,544 3,933,749 
4,197,396 
3,833,546 3,983,093 
4,297,385 
3,838,097 3,989,670 
4,302,575 
3,847,867 3,991,004 
4,324,882 
3,850,885 4,011,198 
4,324,883 
3,875,116 4,024,101 
4,330,666 
3,905,942 
______________________________________ 
Typical polyetherimides useful as component A consist essentially of 
chemically combined units of the formula 
##STR2## 
wherein Q.sup.1 is a divalent aromatic hydrocarbon-based radical and 
Q.sup.2 is a divalent hydrocarbon-based radical. The term "divalent 
hydrocarbon-based radical", as used in the definition of the 
polyetherimides, denotes a divalent radical free from ethylenic and 
acetylenic unsaturation, having a carbon atom directly attached to the 
remainder of the molecule and having predominantly hydrocarbon character 
within the context of this invention. Such radicals include the following: 
(1) Hydrocarbon radicals; that is, aliphatic, alicyclic, aromatic, 
aliphatic- and alicyclic-substituted aromatic, aromatic-substituted 
aliphatic and alicyclic radicals, and the like. Such radicals are known to 
those skilled in the art; examples are ethylene, propylene, trimethylene 
octamethylene, cyclopentylene, cyclohexylene, phenylene, tolylene, 
xylylene, 1,4-naphthylene, 1-5-naphthylene, p,p'-biphenylene and 
2,2-(p,p'-diphenylene)propane (all isomers being included). 
(2) Substituted hydrocarbon radicals; that is, radicals containing 
non-hydrocarbon substituents which, in the context of this invention, do 
not alter the predominantly hydrocarbon character of the radical. Those 
skilled in the art will be aware of suitable substituents; examples are 
halo, alkoxy (especially lower alkoxy), carbalkoxy, nitro, cyano and alkyl 
sulfone. 
(3) Hetero radicals; that is, radicals which, while predominantly 
hydrocarbon in character within the context of this invention, contain 
atoms other than carbon present in a chain or ring otherwise composed of 
carbon atoms. Suitable hetero atoms will be apparent to those skilled in 
the art and include, for example, nitrogen, oxygen, sulfur and silicon. 
For the most part, not more than three substituents or hetero atoms will be 
present for each 10 carbon atoms in the hydrocarbon-based radical. An 
exception comprises molecules in which silicon is a hetero atom, which 
may, for example, contain three hetero atoms for as few as 4 carbon atoms. 
Terms such as "divalent aromatic hydrocarbon-based radical" and the like 
have analogous meanings with respect to aromatic radicals and the like. 
The radical Q.sup.1 in formula II is a divalent aromatic hydrocarbon-based 
radical. It is most often a divalent radical derived from benzene or a 
substituted benzene, biphenyl or a substituted biphenyl, or a 
diphenylalkane which may contain substituents on one or both aromatic 
radicals. The following radicals are preferred as Q.sup.1 : 
##STR3## 
wherein each R.sup.4 is independently hydrogen or methyl, R.sup.5 is a 
straight-chain or branched alkylene radical containing 1-5 carbon atoms 
and is most often the isopropylidene radical, and each X is independently 
hydrogen or halogen (usually chlorine or bromine). Mixtures of the 
foregoing formulas are also contemplated. Especially preferred is the 
radical derived from bisphenol A [i.e. 2,2'-bis(4-hydroxyphenyl)propane] 
by the removal of both hydroxy groups therefrom, and having formula V 
wherein R.sup.5 is isopropylidene and each X is hydrogen. 
Q.sup.2 in formula II is most often an aromatic hydrocarbon radical 
containing about 6-20 carbon atoms or a halogenated derivative thereof, an 
alkylene or cycloalkylene radical containing about 2-20 carbon atoms, or a 
bis-alkylenepoly(dialkylsiloxane) radical. The aromatic hydrocarbon 
radicals are preferred. 
The Q.sup.1-2 radicals of formula II may be conveniently defined in terms 
of typical polyetherimide precursors, herein identified respectively as 
bis-anhydrides of the formula 
##STR4## 
and diamines of the formula 
EQU (VII) H.sub.2 N--Q.sup.2 --NH.sub.2. 
In formula VI, the O--Q.sup.1 --O-- moiety may be attached to the phthalic 
anhydride moieties in the 3-positions or, preferably, the 4-positions, or 
mixtures thereof. Thus, the preferred bis-anhydride of formula VI for use 
according to this invention is 
2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (hereinafter 
"bisphenol A dianhydride"). 
Examples of suitable diamines of formula VII are ethylenediamine, 
propylenediamine, trimethylenediamine, diethylenetriamine, 
triethylenetetramine, heptamethylenediamine, octamethylenediamine, 
2,11-dodecanediamine, 1,12-octadecanediamine, 
3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, 
5-methylnonamethylenediamine, 2,5-dimethylhexamethylenediamine, 
2,2-dimethylpropylenediamine, N-methyl-bis(3-aminopropyl)amine, 
3-methoxyhexamethylenediamine, 1,2-bis(3-aminopropoxy)ethane, 
bis(3-aminopropyl) sulfide, 1,4-cyclohexanediamine, 
bis-(4-aminocyclohexyl)methane, m-phenylenediamine, p-phenylenediamine, 
2,4-diaminotoluene, 2,6-diaminotoluene, m-xylylenediamine, 
p-xylylenediamine, benzidine, 3,3'-dimethyl-benzidine, 
3,3'-dimethoxybenzidine, 1,5-diaminonaphthalene, 
4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 
2,4-bis-(.beta.-amino-t-butyl)toluene, 
bis(p-.beta.-methyl-o-aminopentyl)-benzene, 
1,3-diamino-4-isopropylbenzene, 4,4-diaminodiphenyl sulfone, 
4,4'-diaminodiphenyl ether and bis(3-aminopropyl) tetramethyldisiloxane. 
Mixtures of these diamines may also be used. Particularly preferred are 
the aromatic diamines, especially m-phenylenediamine and 
4,4'-diaminodiphenylmethane; the Q.sup.2 radical is then either 
##STR5## 
The polyetherimides comprising component A generally have a weight average 
molecular weight up to about 3,000,000, preferably about 10,000-100,000 
and most desirably about 50,000-80,000. Polyetherimides of this type are 
commercially available from General Electric Company under the trade name 
ULTEM. 
Component B in the compositions of this invention is at least one block 
poly(esteramide) having formula I. In that formula, the R.sup.1 values are 
divalent aliphatic hydrocarbon-based radicals which usually contain about 
2-10 and preferably about 5-10 carbon atoms, corresponding to the alkylene 
radicals in such dicarboxylic acids as succinic, glutaric, adipic, 
pimelic, sebacic, azelaic and suberic acids, most preferably adipic and 
azelaic acids (i.e., R.sup.1 is tetramethylene or heptamethylene). 
The R.sup.2 values are similar to R.sup.1 and preferably contain about 3-8 
carbon atoms, corresponding to those in such diols as ethylene glycol, 
propylene glycol, trimethylene glycol or, preferably, tetramethylene or 
heptamethylene glycol. Most preferably, the total number of carbon atoms 
in R.sup.1 and R.sup.2 is 10 or 11. 
The R.sup.3 value is a divalent aromatic hydrocarbon-based radical similar 
to those disclosed hereinabove with reference to Q.sup.1 and corresponding 
to various aromatic diamines. Most often, R.sup.3 is at least one of the 
toluylene (any isomer) and 4,4'-methylenebis-phenyl (preferably) radicals. 
As is apparent from the fact that R.sup.1, R.sup.2 and R.sup.3 are 
hydrocarbon-based radicals, they may contain substituents although 
hydrocarbon radicals are preferred. Among the suitable substituents for 
R.sup.1, R.sup.2 and R.sup.3 respectively are carboxy, hydroxy and amino, 
which may themselves be condensed with appropriate groups to form 
crosslinked or graft polymers with pendant polyester, polyamide or 
poly(esteramide) blocks. Each R.sup.1, R.sup.2 and R.sup.3 value is 
defined independently, since mixtures of acids, diols and diamines or 
mixtures with similar trifunctional compounds may be used or a different 
acid may be used in each stage of the preparation of component B. Most 
often, however, all of the R.sup.1, R.sup.2 and R.sup.3 values, 
respectively, are the same. 
The block poly(esteramides) useful as component B may be prepared in two 
stages. In the first stage a commercially available polyester diol of the 
formula 
##STR6## 
such as hexamethylene adipate or tetramethylene azelate, is reacted with 
at least one dicarboxylic acid of the formula R.sup.1 (COOH).sub.2 under 
conditions and in proportions to produce a carboxy-terminated prepolymer 
having the formula 
##STR7## 
wherein R.sup.1-2 and m are as previously defined. In the second stage, 
said prepolymer is reacted with a mixture of additional dicarboxylic acid 
and a diisocyanate of the formula OCN--R.sup.3 --NCO to produce the block 
poly(esteramide). Block polymers of this type are commercially available, 
for example, from Upjohn Company under the trade name ESTAMIDE. They are 
disclosed in Proceedings of the Society of Plastics Engineers, 39th Annual 
Technical Conference (New York, May 4-7, 1981), pp. 421-423 (hereinafter 
"Nelb et al."), which is incorporated by reference herein. 
In the resinous compositions of this invention, components A and B are 
respectively present in the amounts of about 99-1% and about 1-99% by 
weight, respectively. When a predominantly polyetherimide resin having 
improved impact strength is desired, component B may be present in amount 
of about 1-30% and preferably about 5-20% by weight. 
In another embodiment of the invention, the resinous composition 
additionally comprises about 5-25% and preferably about 3-15% by weight of 
(C) at least one poly(alkylene dicarboxylate) which serves as a 
compatibility improver. The dicarboxylate units in component C are derived 
from an aromatic dicarboxylic acid such as isophthalic acid, terephthalic 
acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 
4,4'-biphenyldicarboxylic acid or 4,4'-diphenylmethanedicarboxylic acid. 
The benzenedicarboxylic acids, e.g., isophthalic and terephthalic acids, 
especially the latter, are preferred. The alkylene groups generally 
contain about 2-10 and preferably about 2-6 carbon atoms; they are 
illustrated by ethylene, trimethylene, tetramethylene and hexamethylene, 
with tetramethylene being preferred. Poly(alkylene terephthalates) are 
commercially available from General Electric Company under the trade name 
VALOX. They and the methods for their preparation are disclosed, for 
example, in the following U.S. patents which are incorporated by reference 
herein: Nos. 
2,456,319 
3,047,539 
4,161,469 
4,161,498. 
The preferred poly(alkylene terephthalates) have a number average molecular 
weight of about 20,000-50,000.

The present invention is illustrated by the compositions listed in the 
following table. In these compositions, component A is an ULTEM resin of 
General Electric Company prepared from m-phenylenediamine and bisphenol A 
dianhydride, having an intrinsic viscosity in chloroform at 25.degree. C. 
of 0.47 dl./g., a weight average molecular weight of 75,100 and a number 
average molecular weight of 20,600 as determined by gel permeation 
chromatography referred to polystyrene. Component B is ESTAMIDE 90A as 
described in Nelb et al.; it has a weight average molecular weight of 
about 110,000 as measured by laser light scattering (low angle) in 
dimethylformamide. Component C is a poly(tetramethylene terephthalate) 
having a number average molecular weight of about 34,000 and an intrinsic 
viscosity in a 3:2 mixture of phenol and tetrachloroethane at 30.degree. 
C. of 1.05 dl./g. The Izod impact strengths in the table were determined 
by ASTM procedure D256, Method A. 
______________________________________ 
Component proportions, 
% by weight Impact strength, 
Example A B C ft.-lbs./in. 
______________________________________ 
Control 1 100 -- -- 0.60 
1 95 5 -- 1.44 
2 90 10 -- 1.99 
3 85 15 -- 1.86 
4 75 25 -- 0.94 
Control 2 85 -- 15 0.55 
5 81.0 4.7 14.3 0.94 
6 77.3 9.1 13.6 1.02 
7 74.0 13.0 13.0 1.65 
8 68.0 20.0 12.0 1.29 
9 78.3 13.0 8.7 2.29 
10 82.6 13.0 4.4 2.09 
______________________________________ 
The results in the table show the improved impact strength provided by the 
compositions of this invention in which component B is present, as 
compared with Controls 1 and 2 in which it is absent, especially in the 
further presence of component C.