COMPOUNDS USEFUL AS CURING AGENTS AND PROCESSES FOR THEIR PREPARATION

TRADUCTION NON-DISPONIBLE

English Abstract

ABSTRACT OF THE INVENTION
Novel compounds typified by N,N'-polyoxyalkylene
bis (pyrrolidinone-3-carboxylic acid) are disclosed as
useful as epoxy curing accelerators. Alkali metal salts
thereof are curing agents for isocyanurate foams.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A compound of formula
(R ''')
<IMG>
wherein x is an integer 0-2; a is an integer of at least 2; M is hydrogen
or a cation derived from a strong base; R''' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded; and
the molecular weight of R''' is 200 to about 2000, except that
the molecular weight of R''' is 300 to about 2000 when x is 0 and M is
hydrogen.
2. A compound claimed in claim 1 of formula
( R ''' ) <IMG>
wherein x is an integer 0-2; a is an integer of at least 2; R''' is a
polyoxyalkylene chain having terminal carbon atoms to which the nitrogen
atoms are bonded; and the molecular weight of R ''' is 300 to about 2000.
3. A compound claimed in claim 2 wherein the molecular weight of
R''' is 400 to about 2000.
4. A compound claimed in claim 1 of formula
(R''')
<IMG>
wherein a is an integer of at least 2; R''' is a polyoxyalkylene chain having
29

terminal carbon atoms to which the nitrogen atoms are bonded; and the
molecular weight of R''' is 300 to about 2000.
5. A compound claimed in claim 1 of formula
( R''' ) <IMG>
wherein a is an integer of at least 2; R''' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded; and the
molecular weight of R''' is 200 to about 2000.
6. A compound claimed in claim 1 of formula
( R''' ) <IMG>
wherein a is an integer of at least 2; R''' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded; and
the molecular weight of R''' is 200 to about 2000.
7. A compound claimed in claim 1 of formula
( R''' )
<IMG>
wherein a is an integer of at least 2; R"' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded;
and the molecular weight of R''' is about 200-2000; and M is an alkali metal.
8. A compound claimed in claim 1 of formula
( R''' ) <IMG>

wherein a is an integer of at least 2; R''' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded; and
the molecular weight of R''' is 200 to about 2000; and M is an alkali metal.
9. A compound claimed in claim 1 of formula
( R ''' )
<IMG>
wherein a is an integer of at least 2; R''' is a polyoxyalkylene chain
having terminal carbon atoms to which the nitrogen atoms are bonded; and
the molecular weight of R''' is 200 to about 2000; and M is an alkali metal.
10. A compound claimed in claim 1 of formula
<IMG>
wherein x is an integer of 0-2; R" is a polyoxyalkylene chain having
terminal carbon atoms to which the nitrogen atoms are bonded; and the
molecular weight of R" is 300 to about 2000.
11. Alkali metal N,N'-polyoxyalkylene bis (pyrrolidinone-3-carboxy-
late) as claimed in claim 1.
12. N,N'-polyoxyalkylene bis (pyrrolidinone-3-carboxylic acid)
wherein said polyoxyalkylene has a molecular weight of 300-2100 as claimed
in claim 1.
13. The method of preparing product
( R''' ) <IMG>
31

wherein x is an integer of 0-2; a is an integer of at least 2; and R'''
is a polyoxyalkylene chain of a molecular weight of about 200 to about
2000 having terminal carbon atoms to which the nitrogen atoms are bonded
which comprises the steps of adding to a reaction mixture a moles of
unsaturated carboxylic acid
<IMG>
adding to said reaction mixture about one mole of a polyoxyalkylene poly-
amine
( R''' ) - ( NH2 )a
maintaining said unsaturated carboxylic acid and said polyoxyalkylene
polyamine at ring-forming conditions including temperature of 80°C.-200°C.
thereby forming said product; and recovering said product.
14. The method according to claim 13 of preparing product
<IMG>
wherein x is an integer of 0-2; R" is a polyoxyalkylene chain of molecular
weight of about 200 to about 2000 having terminal carbon atoms to which
the nitrogen atoms are bonded, which comprises the steps of adding to a
reaction mixture two moles of unsaturated carboxylic acid
<IMG>
adding to said reaction mixture about one mole of a polyoxyalkylene diamine
H2N - ( R'' ) - NH2
32

maintaining said unsaturated carboxylic acid and said polyoxyalkylene diamine
at ring-forming conditions including temperature of 80°C.-200°C. thereby
forming said product; and recovering said product.
15. The method of claim 14 wherein said R" chain is a polyoxyethylene
chain having terminal carbon atoms to which the nitrogen atoms are bonded.
16 The method of claim 14 wherein said R" chain is a polyoxypropylene
chain having terminal carbon atoms to which the nitrogen atoms are bonded.
17. The method of claim 14 wherein said acid is itaconic acid.
18. The method of claim 14 wherein said acid is alpha-methylene
glutaric acid.
19. The method of claim 14 wherein said acid is alpha-methylene
adipic acid.
20. The method of curing an uncured epoxy resin which comprises
curing 100 parts of said uncured epoxy resin in the presence of aromatic
curing agent and 1-15 parts of an accelerator
( R''' ) <IMG>
wherein x is an integer of 0-2; a is an integer of at least 2; R''' is a
polyoxyalkylene chain having terminal carbon atoms to which the nitrogen
atoms are bonded; and the molecular weight of R''' is 200 to about 2000.
21. The method according to claim 20 of curing an uncured epoxy resin
which comprises curing 100 parts of said uncured epoxy resin in the presence
of 20-40 parts of aromatic curing agent and 1-15 parts of an accelerator
33

<IMG>
wherein x is an integer of 0-2, and R" is a polyoxyalkylene chain of molecu-
lar weight of about 200 to about 2000 having terminal carbon atoms to which
the nitrogen atoms are bonded.
22. The method of curing an uncured epoxy resin as claimed in
claim 21 wherein x is zero.
23. The method of curing an uncured epoxy resin as claimed in
claim 21 wherein R" is polyoxyethylene.
24. The method of curing an uncured epoxy resin as claimed in
claim 21 wherein said accelerator is the reaction product of two moles of
itaconic acid and about one mole of polyoxyethylene diamine.
25. The method of preparing a cured isocyanurate foam which comprises
reacting an isocyanate with a polyol having at least two active Zerewitinoff-
active hydrogen atoms in the presence of a blowing agent thereby forming a
polyisocyanurate foam; and conducting said reaction in the presence of
0.5-10 parts (per 100 parts of total formulation) of a curing agent
( R''' ) <IMG>
wherein x is an integer 0-2; a is an integer at least 2; M is a cation of
a strong base; R''' is a polyoxyalkylene chain, of a molecular weight of
about 200 to about 2000, having terminal carbon atoms to which the nitrogen
atoms are bonded.
34

26. The method according to claim 25 of preparing cured isocyanuarate
foam which comprises reacting an isocyanate with a polyol having at least
two active Zerewitinoff-active hydrogen atoms in the presence of a blowing
agent thereby forming a polyisocyanurate foam; and conducting said reaction
in the presence of 0.5-10 parts (per 100 parts of total formulation) of
a curing agent
<IMG>
wherein x is an integer 0-2, M is a cation of a strong base, and R" is a
polyoxyalkylene chain of molecular weight of about 200 to about 2000 having
terminal carbon atoms to which the nitrogen atoms are bonded.
27. The method of preparing a cured isocyanurate foam as claimed in
claim 26 wherein, in said curing agent, x is zero.
28. The method of preparing a cured isocyanurate foam as claimed in
claim 26 wherein, in said curing agent, R" is polyoxyethylene.
29. The method of preparing a cured isocyanurate foam as claimed in
claim 26 wherein said curing agent is the reaction product of two moles
of itaconic acid and about one mole of polyoxyethylene diamine.
30. The method of preparing a cured isocyanurate foam as claimed
in claim 26 wherein said curing agent is present as its di-alkali metal
salt.
31. The method of preparing a cured isocyanurate foam as claimed in
claim 26 wherein said curing agent is present as its di-potassium salt.
32. The method of preparing a cured isocyanurate foam as claimed
in claim 26 wherein said curing agent is present as its di-quanternary
ammonium salt.

33. A compound claimed in claim 1 of formula
( R''' ) <IMG>
wherein x is an integer 0-2; a is an integer of at least 3; M is hydrogen,
or a cation of a strong base; and R''' is a polyalkylene chain, of molecular
weight 200 to about 2000, having terminal carbon atoms to which the nitrogen
atoms are bonded.
34. A compound claimed in claim 33 wherein M is an alkali metal.
36

Description

~01~16
This invention relates to novel products
particularly characteri~ed by their use as curing agents
for epoxy resins or isocyanurate foams or as accelerators
for curable epoxy resins.
As is well known to those skilled in the art,
epoxy resins may be cured by the use of aromatic amines
such as (i) methylene dianiline, (ii) the polymeric
condensation produc~ of aniline and formaldehyde, etc.
Typical prior art curing, at elevated temperatures of
80C or higherJ yields products which are resistant to
attack by chemicals, solvents, etc. Curing of epoxy resins
at ambient temperature however yields product coatings
which are undercured, brittle, without strength, and readily
attacked by many chemicals and solvents.
It is an object of this invention to provide
novel products which may be used in curing systems. Other
objects will be apparent to those skilled in the art.
In accordance with certain of its aspects, this
invention is directed to novel products
] ~ C - C - C00M )
~' a
wherein x is an integer 0-2, a is an integer at
least 2, preferably 2-3, M is hydrogen or a cation derived
from a strong base R"' is a polyoxyalkylene chain having
terminal carbon atoms to which the nitrogen atoms are bonded,
.^~.

11~31~16
and the molecular weight of R" ' is 200 to about 2000
except that the molecular weight of R I I is 300 to about
2000 when _ is 0 and M is hydrogen and to the process
for preparing these products which comprises adding
to a reaction mixture a moles of unsaturated carboxylic
acid
HOOC - C = C
Cx
C - COH
o
adding to said reaction mixture about one mole of a
polyoxyalkylene polyamine
r 1 :
L R I~ (NH2)a
maintaining said unsaturated carboxylic acid and said
polyoxyalkylene polyamine at ring-forming conditions
~hereby forming said product; and recovering said
product .
The salts, in which M is a cation derived from
a base~ may be prepared either by reacting the charge acid
in the form of its salt or by reacting the acid product
with a base.
In accordance with certain of its more specific
aspects, this invention is directed to novel products
HOOC - C - C C - C - COOH
C - C / { ~ ` C -- C
O O
wherein x is an integer 0-2, and -R"- is a polyoxyalkalene
chain of molecular weight of about 200-2000 having terminal
carbon atoms to which the nitrogen atoms are bonded~ and to
: ~ - 2 -

416
a process for preparing these products which comprises
adding to a reaction mixture two moles of
unsaturated carboxylic acid
HOOC - C = C
., C
x
C~COH
O
adding to said reaction mixture about one mole
of a polyoxyalkalene diamine
X2N ~ R ~ NH2
maintaining said unsaturated carboxylic acid
and said polyoxyalkylene diamine at ring-forming conditions
thereby forming said product;
and recovering said product.
i,

11~1416
DESCRIPTION OF THE INVENTION
The charge unsaturated carboxylic acids which may be used in prac-
tice of the process of this invention are characterized by the formula:
HOOC - C = C
,C
: C - C - OH
o
wherein x is an integer 0-2. Valence bonds in this structure, or in others
in this specification, may be filled with hydrogen or with inert substituents
which do not interfere with the reaction.
When x is 2~ the acid may be represented by the formula (typified
by alpha-methylene adipic acid):
HOOC - C = C
C
C
C - C - OH
When x is 1, the acid may be represented by the formula (typified
by alpha-methylene glutaric acid):
HOOC - C - C
C
C - C - OH
o
When x is 0, the acid may be represented by the formula (typified
15 by itaconic acid):
HOOC - C = C
C - C - OH
o

1416
.:
In the preferred acid, x is zero. The preferred acid is thus
` itaconic acid.
The polyoxyalkylene polyamines which may be used in practice of
- the process of this invention are characterized by the formula
r ~ O
L
wherein a is an integer preferably 2-3 and R "' is a polyoxyalkylene chain
of molecular weight 200-2000 havlng a terminal carbon atoms to which the
nitrogen atoms are bonded. When a is 3, an illustrative compound of molec-
ular weight of about 400 may be
CH2 ~ OCX2CH(CH3) ~ 2
CH3CH2 ~ C-CH _ ~ OCH CH(CH ~ NH2
g
CH2 ~ L 0CH2CH(CH3 ~ 2
wherein f plus ~ plus h is 5.3 typically as available under the trademark
Jeffamine T-403 of Jefferson Chemical Company.
The preferred amines which may be used in practice of the process
of this invention are polyoxyalkylene diamines characterized by the formula:
H2N ~ R 3 NH2
wherein R" is a polyoxyalkylene chain of molecular weight of about 200-2000
having terminal carbon atoms to which the nitrogen atoms are bonded. R" is
derived from an oxyalkylene group, typified by oxyethylene -CH2CH20-, oxy-
propylene -OCH2CH(CH3)- etc. R" may also be a polyoxyethylene bearing an
added polyoxypropylene (as in the compositions marketed by Jefferson Chemical
Co. under the trademark Jeffamine ED-series) typified by
C,H3 ,CH3 ,CH3 ,CH3
NH2 CHCH2 (OCH2CH)n (OCH2CH2)m (OCH2CH)k OCH2CHNH2
-- 5 --

l4~6
Typical of the polyoxyalkylene diamines which
may be used in practice of the process of this invention
may be those lis-ted in the table:
TABLE
a. The diterminal diamine of polyoxypropylene
of molecular weight 427;
b. The diterminal diamine of polyoxypropylene
of molecular weight 235;
c. The diterminal diamine of polyoxypropylene
of molecular weight 2000;
d. The diterminal diamine of polyoxyethylene
of molecular weight 600; etc.
It will be apparent to those skilled in the
art that many of the suitable polyoxyalkylene polyamines
may be available as and used as commercial mixtures of
several components. Useful commercial materials include
those available under the trademarks Jeffamine D-, T-, and
ED- etc. as marketed by Jefferson Chemical Company.
In practice of the process of this invention,
according to certain of its aspects, an equivalent amount
of unsaturated carboxylic acid is added to a reaction
mixture together with one mole of polyoxyalkylene polya~ine.
The reaction may be carried out in the absence of added
solvent-diluent, but the latter may be present if desired -
including water, toluene, etc. Water is preferably added
in amount of 50 w%-200 w%, say about 100 W% of the amine.

`` 11~14~6
During the reaction, the reaction mixture is
main-tained at temperature of 80C-200C, say 100 C for
4-12 hours~ say 8 hours. During this period, the
following reaction occurs:
HOOC - C = C
a C + ~R~ 3 ~ NH ~ >
: C - C - OH
o
C - C - COOH
~R ~ ] N \ C
C - C
o
In the case of the preferred diamines, the reaction
may be:
XOOC - C = C + H2N ~ R~ 3 NH2 >
2 C
._
C - COH
o
HOOC - C - C
. \ - ~ / C - C - COOH
Cx N - - R~ ~ N Cx
C - C C - C
O O
In the case of one preferred embodiment, itaconic acid -
10 polyoxyethylene di-primary amine, the reacti.on may be:

1~1416
HOOC - C = C ~_
+ H2N~-- CH2CH20-- 2CH2 NH2
C - COH ~ 15
O
,C - C - COOH
HOOC - C - C ~ _ _
/ - CH2CH20 _ 2 2
C - C - 15 C - C
O O
In the case of another preferred embodiment a specific reaction
may be as follows:
HOOC - C = C _ _ l
2 2 ~ CH CH20 _ _ CH2-CH- NH2 >
C - COH
.. _ CH3 - 15 CH3
o
HOOC - C - C \ _ _ C-C-COOH
C - C / l CH CH20 ~ - CH2-CH N /
" CH3 15 CH3 C-C
O
As reaction continues, the water produced by the reaction (in
amount of one mole per mole of acid reacted) may be distilled off. If
desired, the water may be removed during refluxing by azeotropic distil-
lation with eg toluene. Typically at the end of the reaction period,
the reaction mixture may be recovered and filtered, preferably in the
IO presence of added filter aid such as Supercell* brand.
~Trademark - ~ -

The product so obtained is preferably worked up
by stripping, as in a rotary evaporator at ~0C-200C,
say 95C. Stripping may typically be carried out under
vacuum of 0.1-50 mm. Hg, say 0.5 mm. Hg.
Yield is about stoichiometric.
Typical product is recovered as composition which
~depending on the components from which it is prepared
and its molecular weight) may generally be characterized as
a clear viscous liquid, a light brown viscous liquid, a tacky
resin, etc.
These products are generally characterized by their
solubility in alcohols (eg benzyl alcohol, ethanol,
hexanols, etc). They are particularly characterized by
solubility in polymer systems in which they may find use.
These products may be used as recovered or in
the form of solutions in eg benzyl alcohol. They are
characterized when they are in the form of their salts,
eg alkali-metal salts ~preferably potassium K, but also
sodium Na, etc) by their ability to serve as accelerators
for curing epoxy resins. Although they may be used as the
mono-alkali-metal salt, it is preferred to use them in
the form of their di-alkali metal, eg di-potassium, salt.
It is a particular feature of the novel products
of this inven~ion, that when they are present as acids
they serve as curing agents for isocyanurate foamed compositions.

~14~6
The dialkali metal salt iB preferably prepared by
adding to the recovered reaction mixture an equivalent
amount of eg potassium hydroxide in 5%-30%, say 20%
aqueous solution at 20 C-80C, say 50 C. After 10-20
minutes, say 15 minutes agitation, the reaction mixture
may be filtered through a bed of filter aid
and the resulting solution may be used as recovered, eg
as a 10%-80%, say 50% solution. If desired the salt
may be recovered as by evaporation. Both the mono-alkali
and the di-alkali metal salts may be recovered.
In practice of certain of its aspects, this
invention includes the method of preparing a cured
epoxy resin characterized by the fact that when cured
at ambient temperature of 20C-50C, say 30C, it is
found to possess outstanding properties particularly
with respect to strength and retention of strength after
immersion in solvents. Curing agents falling outside
the scope of this invention (such as eg the reaction
product of itaconic acid and eg p-phenylene diamine -
as disclosed in Paytash et al J. A. C. S. 72, 1415-6
(1950) - are not satisfactory as curing accelerators for
- epoxy resins because they are generally high-melting solid
compositions which do not readily blend in with the viscous
epoxy formulation. The novel products of this invention
are particularly characterized by their high compatibility
with the components of the epoxy resins. The fact that
they are generally liquids provides a substantial advantage
to the processor.
-- 10 --

16
An epoxy resin which may be cured by the process
of this invention may typically be one prepared for example
by the reaction of bisphenol-A with epichlorohydrin
C ~ - CHCH2 Cl in the presence of a base - preferably
O
sodium hydroxide. After the condensation is complete,
the crude resin is freed of residual epichlorohydrin, washed
well to remove salt and soluble by-products, and recovered.
Curing of 100 parts of such a resin is
effected in the presence of 20-40 parts, say 30 parts of
an aromatic polyamine curing agent and 1-15 parts of the
accelerator of this invention in eg 10-30 parts, say
20 parts of a solution containing 10-50% of the
accelerator of this invention.
Typical aromatic polyamine curing agent which
may be employed is a condensation product of formaldehyde
and aniline. (as marketed under the trademark JEFFAMI~E
AP-22). Illustrative curing agents may include:
TABLE
methylene dianiline
diamino-diphenyl ether
meta-phenylene diamine
tolylene diamine
-- 11 --
~'

` 11(;~141~
The accelerator of this invention, preferably
in the form of the free acid, is mixed with the liquid
epoxy resin and curing agent; and the mixture is degassed,
poured into aluminum molds, and cured typically for
seven days at ambient temperature.
The product epoxy resin is particularly
characterized by increased strength and by increased
resistance to the deteriorative action of a wide range
of liquids.
In practice of certain of its other aspects, this
invention includes the method of preparing cured
isocyanurate foams particularly characterized by their
desirably longer cream time which desirably allows more
latitude during preparation - i.e. the formulation is
more mobile and handleable during a longer period of time.
An isocyanurate foam which may be cured by the
process of this invention may be one prepared by reacting an
isocyanate typified by a phosgenated condensation
product of aniline and formaldehyde having an NC0
equivalent weight of 134 and a functionality of 2.7.

~ ` 11(~1416
The isocyanate is preferably reacted with a polyol
which has two or more active hydrogen atoms as determined
by the Zerewitinoff method e.g. the polyoxyalkylene
polyols which may be employed in practice of this invention
will be organic compounds having two or more reactive
hydrogen atoms which will react with organic polyfunctional
isocyanates to give urethane polymers. These polyoxyalkylene
polyols typically having a hydroxyl number of 100-800
preferably 200-300, say 200, may include polyesters, polyethers,
polyisocyanate modified polyesters, polyisocyanate modified
polyester amides, alkylene glycols, polyamines, polyiso-
cyanate modified alkylene glycols, etc. It will be
understood that these polyols may have active primary
or secondary hydroxyl groups. The polyol may be a hydroxyl-
containing polyether or polyester including fatty acid
glycerides. Polyesters, which are a preferred type of
polyol, may be obtained by esterification condensation
reaction of e.g. an aliphatic dibasic carboxylic acid with
a glycol or a triol or mixture thereof in proportion such
that the resultant polyesters may contain predominantly
terminal hydroxyl groups. Dibasic carboxylic acids suitable
for preparing polyesters may include aliphatic and aromatic
acids such as adipic acid, fumaric acid, sebacic acid,
phthalic acid; suitable alcohols include ethylene glycol,
diethylene glycol, trimethylol propane, etc. The fatty
acid glycerides may include those having a hydroxyl number
of at least about 50 such as castor oils, hydrogenated
castor oil, or blown natural oils.

Polyethers, another preferred type of
polyol, may include polyalkylene glycols, e.g. polyethylene
glycols and polypropylene glycols preferably having a
molecular weight of at least 60. For convenience, the
term "polyol" or "polyoxyalkylene polyol" may be employed
to designate the substances having two or more active
hydrogen atoms as determined by the Zerewitinoff method,
which may be employed in practice of this invention.
In one aspect of the process of this invention,
the isocyanurate foam may be prepared by reacting (i)
an organic composition having at least two Zerewitinof~
active hydrogen atoms i.e. a "polyol", (ii) an organic
polyfunctional isocyanate, (iii) a cell modifying agent
such as the Dow Corning DC-193 brand trimethyl-end-blocked
dimethyl polysiloxane, (iv) a blowing agent such as the
Kaiser R-ll-B fluorocarbon, trifluoro~ch]oro-methane;
and (v) a di~alkali metal salt of the composition of this
invention.
Formation of product by practice of the process
of this in~ention may be effected by using isocyanate and
polyol in amount to provide an isocyanate index in the
reaction medium of 1-10, preferably 3-6, say 5. Blowing
agent is present in amount of 5-20 parts, preferably 10-14
parts, say 12 parts. Cell modifying agent is present in
amount of 0.1-15 parts, preferably 0.3-0.8 parts, say 0.5
parts. Catalyst of this invention is present in amount
of 0.5-10 parts, preferably 1-4 parts, say 2 parts. (all
parts are parts by weightper 100 parts of total formula-
tion).
- 14 -

" 1101416
The foamed isocyanurate product is found to be desirably
characterized by cream times in excess of about 10 seconds and
typically about 15 seconds, by increased heat distortion, and by
substantially better dimensional stability at low temperature eg
minus 20 F/dry.
DESCRIPTIO~ OF PREFERRED EMBODIMENTS
Practice of the novel process of this invention may be
apparent from the following description of preferred embodiments
wherein, as elsewhere in this specification, all parts are parts
by weight unless otherwise specifically noted.
EXA~PLE I
In this example which represents practice of the process
of this invention, 393 grams (3 moles) of itaconic acid, 600 grams
of water, and 6~o.5 grams of the di-terminal diamine of polyoxy-
propylene (molecular weight about 427, and containing 4.69 milli-
equivalents of primary amine per gram~ are heated to reflux for 8.5
hours. Supercell* filter aid is added and the reaction mixture is
filtered hot and then stripped at 0.5 mm Hg in a rotary drum drier
with a bath temperature of 95C.
On cooling, a clear viscous liquid is recovered having an
acidity of 3.26 milliequivalents per gram and corresponding to the
following formula:
HOOC-C-C \ r ~ /C-C-COOH
¦ N t R~ ~ N
C-C C-C
.. ..
O O
R" is a polyoxypropylene residue (of molecular weight of about 400)
having terminal carbon atoms to which the nitrogen atoms are bonded.
*Trademark - 15 -
i

-`~ llJJ1~16
EXAMPLE II
In this example which represents practice of the process
of this invention, 526 grams (4.03 moles) of itaconic acid, 600 grams
of water, and 470 grams (2 moles) of the diterminal diamine of poly-
oxypropylene (molecular weight about 235, and containing 8.53 milli-
equivalents of primary amine per gram) are heated to reflux for 8
hours. Suepercell* filter aid is added and the reaction mixture is
filtered hot and then stripped at 0.5 mm Hg in a rotary drum drier
with a bath temperature of 95 C.
: 10 On cooling, a light, tacky flowable, viscous resin is re-
covered having an acidity of 4.74 milliequivalents per gram, a nitro-
gen content of 6.35% and corresponding to the following formula:
HOOC-C-C~ C-C-COOH
I > - [ R" ~ ~ ~
C-C C-C
O O
R" is a polyoxypropylene residue (of molecular weight of about 200)
having terminal carbon atoms to which the nitrogen atoms are bonded.
EXAMPLE III
In this example which represents practice of the process
of this invention, 131 grams (1 mole) of itaconic acid, 100 grams of
water, and 1030 grams (0.5 mole) of the di-terminal di-amine of poly-
oxypropylene (molecular weight about 2060, and containing 0.97 milli-
equivalents of primary amine per gram) are heated to reflux of
*Trademark - 16 -
'~

" 11~1~16
98C-100C for 19 hours. Water is removed by azeotropic distillation
with 500 ml of toluene, which is added during the course of the reac-
tion. Supercell* filter aid is added and the reaction mixture is fil-
tered hot and then stripped at 0.5 mm Hg in a rotary drum drier with
a bath temperature of 138C.
On cooling, a light brown viscous liquid is recovered having
an acidity of 0.82 milliequivalents per gram and corresponding to the
following formula
XOOC-C-C / C-C-COOH
¦ ~ ~ R" ~ N
--C C-C
.. ..
O O
R" is a polyoxypropylene residue (of molecular weight of about 2030)
having terminal carbon atoms to which the nitrogen atoms are bonded.
Results comparable to those of Examples I-III are achieved
if the amine is as follows:
Example Amine
IV tri-terminal tri-primary amine
of polyoxypropylene of m. wt.
of 400 (as marketed under the
trademark Jeffamine T-403)
V di-terminal di-primary amine
of polyoxyethylene-polyoxypropylene
of m. wt. of 600 (as marketed
under the trademark Jeffamine ED-
600)
etc.
*Trademark - 17 -

16
Similarly results comparable to those of Examples I-III
are achieved if the acid is
Example Acid
VI alpha-methylene glutaric acid
VII alpha-methylene adipic acid
In certain of the Examples which follow, the following
properties are measured:
Cream time (seconds) - the time interval beginning with mix-
ing of the isocyanate and the B-component (a standard mixture con-
taining the polyol, catalys-t, blowing agent, surfactan-t, and fire
retardant) and ending when the composition changes color from dark
brown to cream color;
Rise time (seconds) - the time interval beginning with mix-
-
ing of the isocyanate and the B-component and ending when the foam
has stopped rising;
Tack-free time (seconds) - The time interval beginning
with mixing of the isocyanate and the B-component and ending when
the surface of the foam ceases to be tacky when touched;
Density (pounds per cubic foot) - the weight of a given
rolume of the productj
- 18 -

4~i
K-factor (watt-inches/C)- as measured by ASTM test
: C 177-63 using Dupont modified guarded hot plate;
lon~ation at Break (%) - as measured by ASTM test
D-638;
Tensile strength (psi) - as measured by ASTM test
D-638;
T ile Modulus (psi) - as measured by ASTM test
D-638;
Flexura~ Stren~th (psi) - as measured by ASTM test
D-790;
F~exural Mod lus (psi) - as measured by ASTM test
D-790i
Shore D-Hardness 0-10 seconds - as measured -by ASTM
test D-2240;
HTD (C, 264 psi/66 psi.) - as measured by ASTM test
D-648;
Izod Impact Strength (~t lbs/in) - as measured by
ASTM test D-256;
Compressive Strength (PSi) - as measured by- ASTM
test D-1625-73;
Heat Distortion (C) - as measured by the temperature
at which a standard sample is depressed 0.1 inches at a load
corresponding to 10~ of its Compressive Strength with Rise;
Closed Cells (%) - as measured by ASTM Test D-2856-70;
Dimensional Stability (%) ~ as measured by ASTM test
D-2126-75 - modified in that the sample actually used had di-
mension of 2" x 2" x 2" instead of 4" x 4" x 4";
-- 19 --

14~6
Fla~mability - as measu-red by the Butler Chimney Test -
ASTM test D-3019-73. Preferred practice based upon the inherent
dangers due to possible flammability of various compositions includ-
ing urethanes, suggest that -the reader be advised that numerical or
other data from this test are not intended to reflect ha~ards pre-
sented by this or any other material under actual fire conditions.
The data represent the behavior of the tested material under specific
controlled test conditions.
EXAMPLE VIII
In this example which represents practice of the process
of this invention, the preparation of a cured isocyanurate foam is
carried out.
A B-component is first prepared containing the following:
(i) 159 grams of polyol - a polyoxyethylene adduct of a
novalak resin of hydroxyl number 187, and an average functionality of
2-5;
(ii) 3 grams of silicone surfacted - the Dow Corning
DC-193 brand of trimethyl and blocked dimethyl polysiloxane;
(iii) 72 grams of fluorocarbon - the Kaiser R-ll-B
brand of trifluoro-chloro-methane;
(iv) 12 grams of a 50% (in polyethylene glycol of
molecular weight 300) solution of the dipotassium salt of the
product of Example I - prepared by addition to the product of
Example I, of an equivalent amount of potassium hydroxide (i.e.
two moles of potassium hydroxide per mole of said product) and of
polyethylene glycol.
_ 20 -

11(~14~6
.
To this B-component is added ~54 grams of
a phosgenated aniline-formaldehyde condensate of
functionality 2.7 and an NC0 equivalent weight of 134.
The mixture is vigorously stirred and then poured into a
box mold and allowed to rise.
Property Time (seconds)
Cream Time 15
Rise Time 140
Tack-free Time 150
The properties of the product foam are listed
in the table which follows Example IX*.
EXAMPLE IX*
In this control example, the procedure of
Example VIII was followed except that
(i) 160.8 grams of polyol was used;
(ii) 6 grams of a 50% solution (in polyoxyethylene
triol ha~ing average molecular weight of 700) of potassium
octoate, a prior art curing agent, was used in place of the
12 grams of the dipotassium salt solution of Example VIII.
( iY) 358.2 grams of isocyanate was used in
place of 354 grams as in Example VIII.
Property Time (Seconds)
Cream Time 5-6
Rise Time 65
Tack-free Time 100
This control foam is less satisfactory than is
the experimental foam. The cream time and the rise time
in particular are much too low to be satisfactory in commer-
cial practice. Eor proper commercial use, the minimum
-21-

1416
cream time in a panel-line formulation ~or example, should
be about 12 seconds and preferably 15-20 seconds as is
the case with Example VIII.

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~1~14~6
The clear superiority o~ the foam of Example ~III
over that of Example IX* is apparent. In addition to the
above comments, particular attention is directed to the
generally superior properties including (i) improved heat
distortion, (ii) ~olume and linear dimensional stability
at low temperature, (iii) weight stability, etc.
EXAMPLE X
In this example which represents practice o~
the process of this invention, the preparation of a cured
epoxy resin is carried out.
The uncured epoxy resin (100 grams) which
is used as charge is identified as a liquid diglyc1dylether
glycol ester of bisphenol A epoxy resin Eq. Wt. 190.
Curing ol the so-prepared epoxy resin (100 g)
is effected by addition thereto of
(i) 30 parts of a condensation product o~
formaldehyde and aniline o~ equivalent weight 50,
a polyaromatic polyamine curing agent, (marketed under
the trademark JEFFAMINE AP-22).
-24_

416
(ii) 20 parts of a 20 w % solution in benzyl alcohol
of the accelerator composition prepared by the process
of Example I.
This mixture of components was mixed thorough'~,
degassed, poured into aluminum molds, and cured for seven
days at ambient conditions ca 25C.
The properties of the Formulation were determined
on samples cut from the castings,
Pro,nerties o~ cured 1/8" casting Value
Izod impact strength (ft-lbs/in.) 0.61
Tensile strength (psi) 9,300
Tensile mod~tlus (psi) 404,ooo
Elongation at break ~) 5.1
Flexural strength ()si) 15 000
Flexural modulus (psi) 42~ OGO
Shore D ~ardness ~0-10 sec.) 86-~4
HDT (C, 264 psi/~6 psi) 44/48
Fle~ral samples were cut and immersed in several
chemicals for 28 days. All tests were conducted at ambient
temperature of ca 25C except that in distilled water which
was carried out at 40C. After remo~al from the chemicals,
flexural strength of the immersed samples was determined.
Pertinent retention of flexural strength T;Jas then computed
with the ~ollowing results:
~ Retention of
Sample immersed in Flexural Strength
Isopropanol 104
Xylene 104
Acetic acid (25~o) 89
Sodium Hydroxi~e (50%) 115
Sulfuric acid (3C~o) 102
Distilled ~ater 88
-25-

?141~
It will be apparent from inspection oP the above
properties that the cured epoxy formulations are outstanding
with respect to strength and retention of strength after
immersion in various chemicals.
EXAMPLE XI*
In this control example, the procedure of
Bxample X is duplicated except that curing is carried
out in the absence of the accelerator.
After seven days cure at ambient temperature,
the formulations were so brittle and undercured that it
was not possible to cut samples for the tests from the
castings. It was apparent that the formulations were
totally unsatisfactory and of low strength.
EXAMPLES XII-XIII*
A liquid accelerating mixture for use in
conJunction with aromatic amine curatives is prepared by
dlssolving 20 g. polyoxypropylene-alpha, omega Bls
(pyrrolidinone-3-carboxylic acid) in 80 g benzyl alcohol.
The above mixture is combined into an epoxy
system as follows
Formulation:
Liquid DGEEA epoxy resin (Equivalent weight 190) 100 parts
Aromatic polyamine Jeffamine AP 22 brand 33 parts
of the condensation product of formaldehyde
and aniline
Accelerator mixture described above 20 parts
The formulation is mixed thoroughly degassed
and poured into aluminum molds and cured ~or seven days
under ambient conditions. The castings are then cut into
samples and tested with the following results:
-26-

~1416
Properties of cured 1/8" casting:
IZOD-impact strength ft.-lbs./in. 0.61
Tensile strength, psi 9300
Tensile modulus, psi 404000
Elongation at break, ~ 5.1
Flexural strength, psi 15000
Flexural modulus, psi. 424000
Shore D hardness, 0-10 sec. 86.84
HDT, C 264 psi/66 psi 44/48
Flexural samples were cut and immersed in
several chemicals for 28 days. After removal from the
chemicals, flexural strength of the immersion samples was
determined. Percent retention of flexural strength was
then computed with the following results -
Sample immersed in Percent Retention, Flex. strength
Isopropanol, R.T. 104
Xylene, RT. 104
Acetic acid, 25% R.T. 89
Sodium hydroxide 50~, R.T. 115
Sulfuric acid, 30%, R.T. 102
Distilled water, 40C 88
Castings cured without the accelerator mixture
(Example XIII*) were brittle and undercured after 7 days
curin; at ambient temperatures. Samples could not be cut
from such castings. In contrast the castings cured with
the accelerator mixture (Example XII) were properly cured,
not brittle and readily cuttable.
R.T. means Room Temperature

lla~4l6
Although this invention has been illustrated by
reference to specific embodiments, it will be apparent
to those skilled in the art that various changes and
modi~ications may be made which clearly fall within the
scope of this invention.
-28_