Note: Descriptions are shown in the official language in which they were submitted.
1125~ RD 10257
The present invention relates to heat curable
compositions comprising a cationically polymerizable organic
material, such as an epoxy resin, and an effective amount of
a diaryliodonium salt used in combination with a cocatalyst
such as a copper salt, an organic acid or mixtures thereof.
As shown in my Canadian application Serial No.
226,107 filed May 2, 1975, diaryliodonium salts of the formula
(I) ( )a (R )b I]c [MQd] ~(d-e)
can be used as a catalyst to promote the photo-initiated cure
of cationically
polymerizable compounds, such as epoxy resins. In my
Canadian application Serial No. 277,774 filed May 5, 1977, I
show that these catalysts can be used in combination with
certain reducing agents, among which are copper salts, to
effect the thermal cure of an epoxy resin. In the above formula
(I), R is a monovalent aromatic organic radical, Rl is a diva-
lent aromatic organic radical, M is a metal or a metalloid, Q is
a halogen selected from fluorine and chlorine, a is an integer
equal to 0 or 2, b is an integer equal to 0 or 1, and when a is
0, b is 1, and when a is 2, b is 0, e is the
valence of M and is an integer equal to 2 to 6 inclusive, d is
greater than e and is an integer havlng a value up to 7, and
c=d-e.
I have found also that heat curable cationically
polymerizable materials can be made by incorporating into epoxy
resins, the diary]iodonium salt of formula (I) in combination
with organic acids, such as aromatic organic carboxylic acids.
In addition, I have further found that besides epoxy resins,
other cationically polymerizable materials, e.g. cyclic ethers
and acetals, lactones, lactams, vinyl prepolymers, can be
1125~50 RD 10257
thermally cured with combinations of such organic acids,
copper salt or mixtures thereof with iodonium salts of formula
(I), or iodonium salts having a non-nucleophilic counterion
such as perchlorate, CF3SO3 and C6H4SO3 . Again, where the
cationically polymerizable material is a phenol-formaldehyde
resin, urea-formaldehyde or melamine-formaldyhyde, iodonium
salts can be used having in addition to MQd and the other
non-nucleophilic counterions previously recited, halide counter-
ions such as Cl, Br, F and I, as well as nitrate, phosphate, etc.
There is provided by the present invention, a
curable composition comprising:
(A) a cationically polymerizable organic material,
and
(B) from 1% to 35% by weight of the curable composition
of a mixture selected from the class consisting of
(i) a mixture of
(a) a diaryliodonium salt of the formula
(II) [(R)a (R )b I] [Y] , and
(b) from 0.01 part to 10 parts by weight
per part of
(a) of a copper salt,
(ii) a mixture of
(c) the diaryliodonium salt of (a), and
(d~ from 0.1 part to 15 parts by weight
per part of ~c) of an organic acid, and
(iii) a mixture of
(e) the diaryliodonium salt of (a),
(f) from 0.01 part to 10 parts by weight
per part of (e) of the copper salt of
(b), and
(g) from 0.1 part to 15 parts by weight per
part of (e) of the organic acid of (d),
- 2 -
RD 10257
:llZS450
where R, Rl, a and b are as previously defined, and Y is a
non-nucleophilic counterion as defined above. Radicals
included by R of formulas (I) and (II) can be the same or
different aromatic carbocylic radicals having from 6 to 20
carbon atoms, which can be substituted with from 1 to 4
monovalent radicals selected from C(l 8) alkoxy, C(1_8)alkyl,
nitro, chloro, etc. R is more particularly, phenyl, chloro-
phenyl, nitrophenyl, methoxyphenyl, pyridyl, etc. Radicals
included by Rl of formulas (I) and (II) are divalent radicals
such as
, etc.
O O ,, R2
where Z is selected from -O-, -S-, S, S, (CH2)n, C, -N-,
R2 is C (1 8) alkyl or C aryl, and n is an integer equal
to 1-8 inclusive.
Metal or metalloids included by M of formulas (I)
and (II) are transition metals such as Sb, Fe, Sn, Bi, Al, Ga,
In, Ti, Zr, Sc, V, Cr, Mn, Cs, rare earth elements such as the
lanthanides, for example, Cd, Pr, Nd, etc., actinides, such as
Th, Pa, U, Np, etc., and metalloids such as B, P, As, etc.
- 3
1~2S~ RD-10257
Complex anions included by MQd (d-e) are, for example BF4 , PF6 ,
AsF6 , SbF6 , FeC14 , SnC16 , SbCl6 , BiC15 , etc.
Iodonium salts included by formulas (I) and (II) are,
for example,
oH3
I+BF4 , I~PF6
,~
I+BF4 . I+SbF6
N02
~ I+BF4 , etc
Iodonium salts of formula (I) can be made by the
procedure in Crivello u.S. Patent 3,981,897, assigned to the same
assignee as the present invention, where contact between an aryl
halonium bisulfate and the corresponding hexafluoro acid or
salt can be effected under aqueous conditions. Iodonium salts
of formulas (I) and (II) also can be made by the procedures
described by O.A. Ptltsyna, M.E. Pudecva et al, Dokl., Akad.
Nauk, SSSR, 163 383 (1964~; Dokl., Chem., 163 671 (1965), F.
Marshall Beringer, M. Drexler, E. M. Gindler, etc., J. Am. Chem.
RD 10257
1~25450
Soc., 75 2705 (1953).
Copper salts which can be used include, for example,
Cu(I) salts such as copper halides, e.g., Cu(I) chloride etc;
Copper (II) salts such as Cu(II) benzoate, Cu(II) acetate,
Cu(II) stearate, Cu(II) gluconate, Cu(II) citrate, etc.
Organic acids and organic acid anhydrides which have
been found effective in combination with the diaryliodonium salts
of formulas (I) and (II) are included by the formulas,
O "
3'' - R (X)f(J)g.
where R3 is a monovalent organic radical selected from C(l 8)
alkyl and C(6 13) aryl, R4 is a polyvalent organic radical
selected from C(2 8) aliphatic and C(6 13) aryl, X is selected
from carboxy and sulfonate, J iB
--C~
- C~o
f is an integer equal to O to 4 inclusive, g is equal to O to 2
and when g is 0, f is equal to 2 to 4, and when g is 1, f is
equal to 1 or 2. Some of the organic acids and organic acid
; anhytrides which can be used are, for example, aliphatic carboxy-
lic acids such as acetic acid, 2-ethylhexanoic acid, hexanoic
acid, oleic acid, stearic acid, palmitic acid, succinic acid,
azeleic acid, etc.; aromatic carboxylic, for example, benzoic
acid, salicylic acid, terephthalic acid, phthalic acid, trimel-
litic acid, trimellitic anhydride, pyromellitic dianhydride,
o-toluic acid; sulfonic acids such as benzene sulfonic acid,
p-toluene sulfonic acid, 4-nitrobenzene sulfonic acid, etc.
1125~5~ RD 10257
Especially preferred results are obtained when the
organic acid used in combination with copper is ascorbic or
a derivative thereof, for example acylated derivative thereof
such as ascorboyl palmitate, ascorboyl oleate, ascorboyl
acetate etc. The mixture of copper, salt and ascorbic
acid forms a redox system, and in conjunction with the
iodonium catalst permits a E~apid cure of cationically
polymerizable material without the addition of external heat.
In instances where an organic solvent is present with the
cationically polymerizable material, the autogenous heat
of cure of the polymerizable material may be sufficient
to volatalize the solvent, so as to permit the generation
of resin foams.
In the practice of this aspect of the invention
there will normally be present, per part of iodonium salt
catalyst of formula II, 0.5 to 10 parts by weight of the
copper salt, and 0.5 to 10 parts by weight of the ascorbic
acid or a suitable derivative. Where it is desired to
produce a foam, there will be in addition about 1% to about
30% by weight of the curable composition of a volatile, inert
organic solvent.
The thermally activated compositions of the present
invention can be made by blending the polymerizable organic
material with at least an effective amount (i.e. at least
about 0.1~ by weight) of the diaryliodonium salt and in
further combination, as previously defined, with the other
cocatalysts such as the copper salt, organic acid, organic
acid anhydride, etc. The resulting curable composition can
be in the form of a varnish having a viscosity of from 1
to 100,000 centipoises at 25C or a free flowing powder,
depending upon the nature of the cationically polymerizable
organic material. The curable compositions can be applied
~12~0 RD 10257
to a variety of substrates by conventional means and cure
to the tack-free state within 0.5 to 20 minutes, depending
upon the temperature emp oyed. In certain instances, an
organic solvent such as nitromethane, acetonitrile, can be
used to facilitate the mixing of various ingredients. The
diaryliodonium salts can be formed in situ if desired.
The autogenous curing compositions may be similarly
prepared by simply mixing the various components where it is
desired to employ the composition immediately. Where it is
desired to have a system of long shelf life it will normally C
be made as a two component system. Thus in the case of an
epoxy resin, part of the resin maybe mixed with the diary-
liodonium salt, and the remainder mixed with the redox
catalyst. Both components have a very long shelf life at
normal ambient temperatures. In instances where a foam
is desired, a volatile organic solvent can be combined with
either of the aforementioned stable mixtures or can be
introduced separately during the mixing of the respective
mixtures. Suitable volatile organic solvents which can
be employed to produce rigid or flexible foams in the
practice of the present invention are, for example, acetone,
hexane, trichlorofluoromethane, n-pentane, 2-methylhexane,
dichloromethane, l,1,2-trichlorotrifluoroethane, methyl
alcohol, ethyl alcohol, methyl ethyl ketone, etc. In addition
to such volatile solvents, there are also included
thermally unstable compounds such as ethylene carbonate,
ammonium nitrite, benzoyl peroxide, cyclohexanone peroxide,
methyl ethyl ketone peroxide, 2,2'-azobis(2-methylpropioni-
trile), azobisformamide, etc.
The foamable mixture can be injection molded into
suitable receptacles, such as refrigerator dooxs and the like
to provide for the production of insulating foams. Thorough,
-- 7 --
RD 10257
~iZS450
mixing of the ingredients has been found to facilitate
the production of a uniform foam which can be achieved
by the employment of a mechanical stirrer or agitator, as
generally utilized in the art.
In instances where a flexible filmar foam is
desired, the above described epoxy resin can be combined
with polycaprolactones or any hydroxy terminated polyester
to render the products made in accordance with the present
invention more flexible. Typical hydroxy terminated
polycaprotactones are Niax polyols, manufactured by
the Union Carbide Corporation. There can be utilized from
1 to 60 parts of th~ hydroxy terminated polyester per
part of the epoxy resin and preferably from 1 to 50 parts.
Included by the hydroxy terminated polyesters which can be
employed in the practice of the present invention to flex-
ibilize cured epoxy resin films or foams are compounds of
the formula,
CH3 C
, i 11
~` H ( o-cH2-c-cH2-o-c~ CH2~4 C ~ OH
CH
where t is an integer having an average value of from 1 to
100.
~- In addition the above curable compositions may
include additives to enhance surface properties and to control
foam cell size. Among such additives are polyalkylene oxide
surfactants and silicone fluids.
The term "epoxy resin" as utilized in the description
of the cationically polymerizable compositions of the present in-
vention, includes any monomeric, dimeric or oligomeric or poly-
112S450
RD-10257
meric epoxy material containing one or a plurality oE epoxy func
tional groups. For example, those resins which result from the
reaction of bisphenol-A (4,4'-isopropylidenediphenol) and epi-
chlorohydrin, or bythe reaction of low molecular weight phenol-
formaldehyde resin (Novolak resin) with epichlorohydrin, can be
used alone or in combination with an epoxy containing compound
as a reactive diluent. Such diluents as phenyl glycidyl ether,
4-vinylcyclohexene dioxide, limonene dioxide, 1,2-cyclohexene
oxide, glycidyl acrylate, glycidyl methacrylate, styrene oxide~
allyl glycidyl ether, etc., may be added as viscosity modifying
agents.
In addition, the range of these compounds can be c~
tended to include polymeric materials containing terminal or - ~
pendant epoxy groups. Examples of these compounds are vinyl co-
polymers containing glycidyl acrylate or methacrylate as one o~
the comonomers. Other classes of epoxy containing polymers amen-
able to cure using the above catalysts are epoxysiloxane resins,
epoxy-polyurethanes and epoxy-polyesters. Such polymers usually
have epoxy functional groups at the ends of their chains. Epoxy-
siloxane resins and method for making are more particularly shown
by E.P. Plueddemann and G. Fanger, J. Am. Chem. Soc. 80 632-5
(1959). As described in the literature, epoxy resins can also
be modified in a number o~ standard ways such as reaction wi~h
amines, carboxylic acids, thiols, phenols, alcohols, etc., as
shown in patent 2,935,488; 3,235,620; 3,369,055, 3,379,653;
3,398,211, 3,403,199; 3,563,840; 3,567,797; 3,677,995; etc.
Further coreactants which can be used with epoxy resins are
hydroxy terminated flexibilizers such as hydroxy terminated p~1y-
esters, shown in the Encyclopedia of Polymer Science and Tecl-;nol-
ogy, Vol. 6, 1967, Interscience Publishers, New York, pp. 209-2-il
and particularly p. 238.
g _
,. . . . . ..
~125a~SO
RD-10257
Included by the thermosetting organic condensation
resins ~ formaldehyde which can be used in the practice of the
present invention are, for example, urea type resins, such as
[ CH2=N- CONH2 ] X ~ H20
[cH2=NcoNH2]xcH3cooH
[CH2=NCONHCH2NHCONHCH20H]X
phenol-formaldehyde type resin, such as
OH
H O-CH ~ CH ~ OH
CH2-0 H
H t OCH2~ CH21--OH
CH3 n
10where x and n are integers having a value of 1 or greater;
HO-CH2 ~ H20H
-- ~1
HO-CH2~ CH20H
C4HgOCH~H2oH
P N
Ho-cH2 ~ CH2-OH
C4Hg-O-CH2 ~ N / ~CH20-C4Hg . etc.
':
-- 10 --
1~25~50
RD-10257
In addition, there can be used melamine thiourea
resins, melamine, or urea aldehyde resins, cresol-formaldehyde
resins and combinations with other carboxy, hydroxyl, amino and
mercapto containing resins, such as polyesters, alkyds and poly-
sul~ides.
Some of the vinyl organic prepolymers which can be
used to make the polymerizable compositions of the present
invention are, for example, CH2=CH-0-(CH2-CH20)n.-CH=C112, where
n' is a positive integer having-a value ~p to about 1000 or
a higher; multi-functional vinylethers, such as 1,2,3-propane
trivinylether, trimethylolpropane trivinylether, prepolymers
havlng the formulJ, ~ CH2 ~ , , and
CH=CH2
; low molecular weight polybutadiene having a viscosity of from
200 to 10,000 centipoises at 25C, etc. Products resulting from
the cure of such compositions can be used as printing inks and
other applications typical of thermosetting resins.
A further category of the organic materials which
can be used to make the polymeriæable composition~ are cyclic
ethers which are convertible to thermoplastics. Included by
such cyclic ethers are, for example, oxetanes such as 3,3-bis-
chloromethyloxetane,alkoxyoxetanes as shown by Schroeter Patent
3,673,216, assigned to the same assignee as the present inven-
tion; oxolanes such as tetrahydrofuran, oxepanes, oxygen con-
taining spiro compounds, trioxane, dioxolane, etc.
In addition to cyclic ethers there are also inclu~ed
cyclic esters such as ~-lactones, for example propiolactone,
cyclic amines, such as 1,3,3-trimethyl-azetidine and organo-
-- 11 --
~ S~ RD 10257
silicon cyclics, for example, materials included by the formula,
~ 2 t
m
where R" can be the same or different monovalent organic radical such as
methyl or phenyl and m is an integer equal to 3 to 8 inclusive. An example
of an organosilicon cyclic is hexamethyl trisiloxane, octamethyl tetrasilox-
ane, etc. The products made in accordance with the present invention are
high molecular weight oils and gums. In addition, the curable compositions
may contain inactive ingredients, such as silica, talc, clay, glass fibers,
extenders, hydrated alumina, carbon fiber process aids, etc., in amounts of
up to 500 parts of filler per 100 parts of cationically polymeriæable
organic material. The curable compositions can be applied to such substrates
as metal, rubber, plastic, molded parts or films, paper, wood, glass,
cloth, concrete, ceramic, etc.
Some of the applications in which the curable compositions of
the present invention can be used are, for example, protective, decorative
and insulating coatings, pitting compounds, printing inks, sealants,
adhesives, molding compounds, wire insulation, textile coatings, laminates,
impregnated tapes, varnishes etc.
In order that those skilled in the art will be better able to
practice the invention, the following examples are given by way of illus-
tration and not by way of limitation. All parts are by weight.
Example 1~
Various blends of Shell Epon 828 , bisphenol-A-diglycidyl ether,
and a diaryliodonium-Cu(II) salt catalyst were heated for about 5 minutes
to determine their respective cure temperatures, "CT". A wide range of
diaryliodonium MQd salts of formula (I) in combination with several Cu(II)
salts were utilized. The following table shows the results obtained
where the weight percent is shown of diaryliodonium salt and the Cu(II)
salt in the respective blends, based on total weight of mixture,
and "Ph" is phenyl.
l~Z~ 5~
RD-10257
_donium Salt (2%) Cu(II) Salt (WT%) C~( C)
Ph2IAsF6 None 215
" benzoate (0.04) 112
" benzoate (0.5) 105
Ph2ISbF6 None 171
.. benzoate (0.5) 10~
Ph2IBF4 None 210
benzoate ~0.5) 135
Ph21BF4
Ph IAsF stearate (0.2) 148
2 6 stearate (0.5) 115
(4-t-butPh)2IAsF6 benzoate (0.5) 106
(4-Cl-Ph)2IA2F6 benzoate (0.5) 108
(4-CH3-Ph)2IAsF6 benzoate (0.5) 142
Ph2IASF6 acetate (0.5)
In the above table, cure was determined by applying
the curable mixture onto a steel substrate and heating it in an
oven until the applied curable mixture formed a tack-free cured
film.
; Example 2.
A mixture of bisphenol-A diglycidyl ether and 3% by
weight of diphenyliodonium hexafluoroarsenate was respectively
blended with 3% of benzoic acid and 6 and 10% of trimellitic
anhydride by weight. The resulting curable mixtures were then
heated at a rate of 10C per minute to determine the minimum
; 25 temperature required to gel the bis-epoxide. It was found that
a temperature of 225C was required to gel the bis-epoxide when
the mixture was free of aromatic carboxylic acid. However, th?
3% by weight benzoic acid mixture gelled at 120C, while the
- 13 -
~1;25~50
RD-10257
6 and 10% trimellitic anhydride mixture gelled at 150-160C,
re~;pectively.
Example 3.
A variety of curable mixtures were prepared utilizing
3,4'-epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate,
3% by weight of diphenyliodonium hexafluoroarsenate and a range
of between about 3%-6% by weight of various organic acids. The
mixtures were heated in an oil bath to determine the respective
gel times. The temperature of the oil bath was 170C. The
following results were obtained, where "Acid" signifies the
organic acid or organic acid anhydride employed.
Acid Weight (%) Gel Time(sec)
None ~900
Acetic 6 17C
Stearic 6 215
Benzene sulfonic 6 135
Trimellitic anhydride 6 160
'' " 10 15Q
COO~ 6
OH
CH
HC ~ - COOH 3 225
CH3
HO ~ COOH 6 165
N02
~ COOH 3 225
N02
OH
COOH 6 165
- 14 -
~12~5~
RD-10257
continued:
_ Acid Weight (%) Gel Time(seç)
Cl ~ COOH 6 115
Cl
HO ~ COOH 6 123
OH
The above results show that a significant reduction~
in gel time was achieved when the organic acid was utilized in
combination with the diaryliodonium salt.
Example 4.
There were added 0.2 part of diphenyliodonium hexa-
fluoroarsenate, 0.1 part of benzoic acid and 0.05 part copper
benzoate to 10 parts of an allyl ether resole condensation
product of phenol and formaldehyde containing multifunctional
hydroxy methyl groups (Methylon ~5108 resin of the General
Electric Company). The mixture was stirred in an oil bath at
120C. The mixture gelled and hardened at 120C to a rigid
crosslinked mass within 5 minutes. The composition is useful
as a potting material for electrical components.
Example 5.
There was added 0.1 part of copper benzoate and 0.2
part of diphenyliodonium hexafluoroarsenate to 10 parts capro-
lactone. The mixture was heated for 20 minutes at 120C, The
resulting highly viscous reaction mixture was poured into
methanol. There was obtained 9.5 parts polycaprolactone hav-
ing an intrinsic viscosity in methylene chloride of 0.4 dl/g.
- 15 -
ilZ54SO
RD-10257
Example 6 ~
Ten parts of a mixture of 3% by weight of diphenyl-
iodonium hexafluoroarsenate, 6~/o by weight of copper benzoate,
51% by weight of cycloaliphatic bisepoxide (CY-179TM, of the Ciba
Geigy Company) and 40% by weight of hydroxyl terminated polyester
(R-101-110 , of the Hooker Chemical company) was placed in
an aluminum cup. The mixture was heated for 10 minutes at 130C.
On cooling, there was obtained a rubbery material capable of
bçing flexed 180C without breaking.
ExamPle 7.
Graphite cloth (MorganiteTM. I produced by the Whittaker
Corporation, Costa Messa, California) was impregnated with the
; following mixture:
Epoxy cresol novolac (ECN 1299) 20 parts
of the Ciba Geigy Co.
Diphenyliodonium hexafluoroarsenate 3 parts
Diglycidyl ether of bisphenol-A (Epon 828) 80 parts
of the Shell Chemical Company
Trimellitic anhydride 10 parts
Copper benzoate 1 part
; The cloth was then cut into 4" x 6 " pieces. A four layer lam-
inate was made from the aforementioned piece. The laminate was
then pressed at 165-170C at 50 p9i for 3 minutes. There is
obtained a rigid cured solvent resistant graphite fiber rein-
forced laminate having excellent mechanical properties.
Example 8.
A molding compound was made by mixing 394 parts of
a granulated filler-epoxy preblend, 18.75 parts of trimellit~c
anhydride, 3.75 parts of diphenyliodonium hexafluoroarsenate,
0.15 part of copper stearate, 9 parts of powdered carnauba wax
- 16 -
~;25~
RD-10257
6 parts of powdered Cornelius wax, and 75 parts of 1/4"
chopped glass fiber. The filler-epoxy preblend was based on
the use of 8,365 parts of hydrated alumina and 1,050 parts of
titanium dioxide, 3,500 parts of pulverized Epi-Rez M SU-8 (an
epoxy novolac resin of the Celanese Chemical Company~ and 875
~arts of pulverized Epon 1009 M, a BPA epoxy resin o the Shell
Chemical Company. The filler-epoxy preblend was initially
sintered, followed by compounding it with a Sterling extruder.
The molding compound was granulated for evaluation
after it had been sheeted on a roll mill. The granulated mold-
ing material free of particles finer than 20 mesh was molded
in accordance with ASTM D955 for 3-5 minutes at 350F at a
pressure of 2000-3000 psi. There were obtained ASTM discs and
dog bone specimens providing the following properties:
Preforms
Moldin~ Properties Dry Powder (preheated) Test Method
Molding Temp. 350 F 5U F
Cure Cycle 45 sec.
Mold Shrinkage 3.6 mil/in D955 (ASTM~
- 5 in bars
PhYsical Properties
Spec~Ic Gravity 1.~3-1.~5 D570
Hardness, Rockwell M88~10 M110~4 D785
Mechanical Properties
Tensile Strength (psi) 4300~3Q0 5100~600 D638
Flexural Strength (psi) 10900~400 9800~500 D790
Compressive Strength (psi) 18100~500 17000+1500 D695
Drop Ball (1/2 lb, in) - 10+1 10~1
Notched Iæod (ft-lb/in) 0.37~.04 0.53~.1 D25&
Thermal Properties
HDT 460+7F 435+13F D648
Electrical Properties
Arc Resistance 199+1 196+2 D495
Example 9.
There was formulated, 33.5 parts of platy talc,
33.5 parts of hydrated alumina, 13 parts of trimellitic anhy-
- 17 -
~Z54SO
RD-10257
dride, 3.9 parts of diphenyliodonium hexafluoroarsenate, 3.6
parts of powdered paraffin wax and 0.~ part of stearic acid with
26~ parts of a granulated preblend of hydrated alumina, platy
talc and epoxy resin, and 145 parts of epoxy coated glass fiber.
The granulated preblend of platy talc and hydrated alumina w~s
initially prepared from ~ mixture o~ 140 parts of platy talc,
140 parts of hydrated alumina, 45.75 parts of Epon 1001 BPA
epoxy resin of the Shell Chemical Company, and 48.75 parts of
E~N 1299 , an epoxy cresol novolac resin of the Ciba-Geigy
Chemical Company. The epoxy coated glass fiber was prepared
from a mixture of 75 parts of chopped glass fibers, 32.5 parts
of Epon 1001 and 32,5 parts of ECN 1299.
The above formulation was then dry blended and roll
milled at temperatures in the range of between 30-90C for
several minutes. The resulting mixture was then further tumble
blended with additional stearic acid sfter being granulated.
Several ASTM specimens were prepared in accordance
with the procedures of Example 8. The resulting specimens
provided the following properties:
Test
Molding Properties (Compression) Method
Molding temperature 350 F
Cure cycle
- Dry powder 60 sec.
- Preforms (preheated) 40 sec.
Mold shrinkage
- 5xl/2xl/2 bars (mils/in) 2 1+0 1 D955 (ASTM)
Physical Properties
Speci~ic gravity 1.93
Water absorption D570
- 25C (24 hrs, %) 0.06
- 100C (2 hrs, %) 0.22
Burning characteristics V-0 UL-94
- Hardness, Rockwell M97+10 D7B5
- 18 -
~ZS~50 RD 10 257
continued:
Test
Method
Mechanical Properties
Tensile strength (psi) 5700l1700 D638
Flexural strength (psi) 6 11,000+2000 D790
Flexural Modulus (psi x 10 ) 1.84+0.14
Compressive Strength (psi) 16,000+1900 D695
Notched Izod (ft-lb/in)0.57+0.01 D256
Thermal Properties
Thermal coefficient of 5
expansion (in/inFxlO ) 14. D696
Heat deflection temperature
(265 psi) 475F D648
- Flex. strength (% retention) 9800+1200
(91%+22%)
- Flex. modulus (% retention) 1.84+0.09
(100%+8%)
Electrical Properties
Arc resistance, sec.199+5 D495
Example 10
There was added a mixture of copper salt and
ascorbic acid in n-butanol to a 3% solution of diphenylio-
donium hexafluoroarsenate in 3,4-epoxycyclohexylmethyl-3',-
4'-epoxycyclohexanecarboxylate. A series of mixtures were
made following the procedure using various copper compounds
to produce mixtures having an average of from 1-3% by weight
of the copper salt and from 0.5 to 3% by weight of ascorbic
acid, based on the weight of the mixture. The cure time
(sec) was recorded which represented the time for
the respective mixtures to harden when examined in 4
dram vials. The following results were obtained where
the percent shown is based on the weight % of the ingredient
in the mixture:
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l~S~ RD 10257
Copper II Compound Ascorbic Acid Cure Time
~T (%) WT (%) (sec)
- - No Cure
- 3 No Cure
Copper benzoate (3) - No Cure
Copper benzoate (3) 3 380
Copper benzoate (l) .05 120
Copper benzoate (1) 1 ~60
Copper stearate (1) 1 60-120
Copper acetate (3) 3 30
Copper formate (3) 3 30
Copper benzoate (l) 2 ~30
The above results show the need for copper
salts and the ascorbic acid to achieve a cure of the epoxy
resin and the effect on the cure time when the weight per-
cent of the respective ingredient is varied at ambient
conditions.
Example 11
A study was made with a mixture of an epoxy
resin containing 1% by weight of copper benzoate and 3%
by weight of ascorbic acid to determine whether the cure
time would be affected by varying the type of diarliodonium
salt used. The redox catalyst was added as a suspension
in ethylene glycol to the epoxy resin of Example lO which
contained 3% by weight of diaryliodonium salt. The
following results were obtained:.
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1125450 RD l 0 2 5 7
Diaryliodonium Salt Cure Time ( sec)
((~ I AsF6 75
Cl~ I+AsF 6 114
[~CH3) 3C~I AsF6 174
( ~ I AsF6 102
N62 2
3 3C CO~ I SbF6 190
[((:H3).3C ~ F6 300
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~ 0 RD 10257
The above results show that the structure of
the anion and the cation of the diaryliodonium salt had a
significant effect on the epoxy resin cure time at ambient
conditions.
Example 12.
The procedure of Example 10 was repeated, except
that 1% by weight of ascorboyl palmitate in 0.3% by weight
n-butanol, based on the weight of the resulting curable
composition, was used in place of ascorbic acid. It was
found that the resulting composition cured within 3-4 minutes
without the use of external heat under atmospheric conditions.
Example 13.
There was added 0.1 part of copper benzoate and 0.2
part of ascrobic acid in combination with 0.6 part of
acetone to a mixture with stirring consisting of 6 parts of
3,4-epoxycyclohexylmethyl-3'j4'-epoxycyclohexane carboxylate
and 0.2 part of diphenyliodonium hexafluoroarsenate. The
mixture was stirred vigorously and then allowed to stand
in a small container. After about 150 seconds, the mixture
foamed and filled the container. There was obtained a
rigid foam having a density of approximately 0.05 g/cc.
The foam was suitable as a thermal insulator for a refriger-
ator.
The above procedure was repeated, except that
Freon 11 was used in place of acetone. A foam was formed
similar to the foam obtained using acetone.
- Example 14.
A mixture of 6 parts of 3,4-epoxycyclohexylmethyl-3',
4'-epoxycyclohexanecarboxylate and 3 parts of polycaprol-
actone, PCP0300TM, a product of the Union Carbide Corporation,
was mixed with 0.2 part of diphenyliodonium hexafluoroarsenate,
0.1 part of copper benzoate, 0.2 part of ascorbic acid and
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~25450 RD 10257
0.6 part of acetone. The mixture was vigorously stirred in
a small glass container approximately 1/3 filled. In
approximately 150 seconds the reaction mixture foamed and
filled the container and then overflowed the container.
The resulting foam was found to be flexible, based on the
fact that it could be flexed at 180 without being
permanently set. The density of the foam was approximately
the same as in Example 4.
Example 15
.
There was added to a 1.5% solution of diphenylio-
donium hexafluoroarsenate in 2-chloroethylvinyl ether, 0.5%
of copper benzoate and 0.5~ of ascorbic acid. A vigorous
reaction occurred within 3 minutes. The reaction mixture
was then poured into methanol after standing an additional
15 minutes. There was obtained a 61.3~ yield of poly-
chloroethylvinyl ether after the resulting product was
washed in methanol and dryed.
The above procedure was repeated, except that
trimethyleneoxide was used in place of 2-chloroethylvinyl
ether and the reaction was performed at 0C. A 41.4%
yield of polytrimethylene oxide was obtained.
Example 16.
There was added 0.3 part of copper benzoate
and 0.3 part of ascorbic acid suspended in ethylene
glycol to 9.4 parts of an acid reactive resole phenol
formaldehyde based resin having allylic ether functional
groups (Methylon 11 of the General Electric CompanY).
The mixture was stirred thoroughly and poured into a
shallow al~uminum cup. After 30 minutes, the phenol
formaldehyde resin was found to have cured to a hard
rigid solid.
Although the above examples are directed to only
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~ 5 0 RD 10257
a few of the very many variables which can be ~mployed
:in the practice of the method of the present invention,
as well as to the wide variety of curable compositions
resulting therefrom, it should be understood that a much
broader variety of cationically polymerizable materials
can be utilized in combination with diaryliodonium salts,
copper salts and acid derivatives as set forth in the
description preceding these examples.
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