Note: Descriptions are shown in the official language in which they were submitted.
P ~ 737,
Prior to the present invention, it ~,7a.5 gen~r311-y
known that a variety of organic materials such as vinyl
monomers possessing a high electron densit~ in the double
bond, were subject to cationic polymerization. A srnall
amount of a Lewis Acid catalyst, such as SnC14, SbF5, AsF5,
etc. readily polymerizes vinyl monomers such as styrene,
butadiene, vinyl alkyl ethers, etc. It is often di~ficult,
however, to genexate the Lewis Acid catalyst at the appro-
priate time for polymerization, or have it properly dispersed
throughout the vinyl monomer to achieve uniform results.
It is also known to cure epoxy resins as "one package"
systems, based on the employment of a Lewis Acid catalyst in
the form of an amine complex such as boron trirluoride-monoethyl
amine~ The Lewis Acid is released on heating; cure takes place
within 1 to 8 hours and can require a temperature of 160 C.
and higher. As a result, these one package epoxy compositions
cannot be employed to coat heat sensitive devices such as
delicate electronic components. Nor can epoxy or other monomers
having low boiling points be used due to the resulting losses
to evaporation during cure.
r 3~ 7 D ~ 6
i"~ As shown by Schlesinger, U.S. Patent 3,70~, 9G-issued
'~J ~ r ~ /13
, cextain photosensitive aromatic diazonium
salts can be employed to cure epoxy resins~ When photolyzed~
these aromatic diazonium salts are capable of releasing, in
situ, a Lewis Acid catalyst which can initiate the rapid
polymerization or the epoxy resin. However, even though these
one package epoxy resin mixtures can provide fast curing
compositions, a stabilizer must be used to minimize cure in
the dark during storage of these mixtures. Despite these
measures, gellation of the mixture can occur even in -the
absence of light. In addition, nitrogen is released during
12 7~46 P~-7313
UV-cure, which can result in film imperfectionss Diazoniu7n
salts are generally thermally unstable, rendering t'ne u,e of
such materials hazardous because of the possi~ility of run-a-;1ay
decomposition.
Additional organic materials such as aldehydes,
cyclic ethers and cyclic esters also can undergo cationic
polymeriæation in the presence of trace amounts of Lewis hcid3
Such materials when catalyzed, can be employed in coating
applications, as encapsulants, a:nd for a variety of thermo-
plastic applications. Howe~er, optimum results cannot beachieved because it is difficult to achieve dispersion or
generation of the Lewis Acid in a desirable manner. A further
description of the principles by which cationic polymerization
of the above described organic materials can be achieved with
Lewis Acids is described in Princ ples of Polvmer Chemistry,
pp 217-222 by P.J. Flory, Cornell University Press, Ithica,
~ew YOrk (1953), and Polymer Reviews by J. Furukawa and
T. Saegusa, Interscience Publishers, New York (1953). Another
class of materials which underyoes cationic polymerization
in the presence of Lewis Acids is organosilicon cyclics as
shown by W. ~oll, The Chemistry and Technoloqy of Silicones,
pp 219-226, Academic Press, New York (1968).
The present inven~ion is based on the discovery
that certain photosensitive aromatic halonium salts, as
~Z7464~i
~ 7i7
illustrated by 1he formula,
¦; ~ C~ ~2 I ~ 1BF4~
can be a sou-rce of Lewis Acids such as boron trifluoride,
.~7~ ' p~ VS,D~ D r~S
he~ pentafluoride, arsenic pentafluori.de, etc , -.7hen
exposed to radiant energy, A varie~y of radiation poly~r:e-ri-
zable compositions are provided by incorporating the photo-
sensitive aromatic halonium salt into a cationically poly-
merizable organic material. Unlike polymerizable ~olnposit~ons
containing the above described diazonium salts, the compo-
sitions of the present invention, which can be in the fonm
of a solid or liquid, do not require a s~abilizer. Even
after e~tended shelf periods, the polymerizable compositions
of the present invention do not exhibit any signi~can~
change in properties In addition, there is no problem with
bubbling as characteri~ed by organic resin compositions con-
tainiTlg diazonium salts.
The polymerizable compositions of the present inven-
tion can be used as moldi.ng and extrusi.on resins~ adheslves,
caulks, coatings, printing inks, impregnated tapes~ insula-
ti.on, seal.ants, blood plasma extenders, lubricants, etc
The aromatic halonium salts utili zed in the compo-
si.tions of the present invention can be more particul~rly
defined by the following formula,
(I) ~ (R)a(~ )b X ¦ ~ MQd
RD-7373
~ ~7~
where R is a monovalent aromatic organic radical; R
is a divalent aromatic organic radical; X is a halogen;
M is a metal or a me-talloid; Q is a halogen, such
as Cl, F, Br, I, etc.; a is an integer equal to 0 or 2,
b is an integer equal to 0 or 1, and the sum of
a -~ 2b is equal to 2;
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 having
a value up to 7; and
c = d - e.
Radicals included by R can be the same or
different, aromatic carbocyclic or heterocyclic radical
having from 6 to 20 carbon atoms, which can be substituted
with from 1 to 4 monovalent radicals selected from
(1-8) alkoxy, C(1-8) alkyl, nitro, chloro, etc., R is more
particularly, phenyl, chlorophenyl, nitrophenyl, methoxyphenyl,
pyridyl, etc. Radicals included by Rl are divalent radicals
such as
@ ~ ~ 2~n ~
Complex anions included by MQd (d e)~ of formula I are, for
example, BF4 , PF6 , AsF6 , SbF6 , FeCl4 , SnC16 , SbC16 ,
BiC15 , AlF6 , GaC14 , InF4 , TiF6 ~ ZrF6 , etc- Metal
or metalloids included by M of formula I 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,
~274646
RD-7373
for example, Cd, Pr, Nd, ete. actinides such as Th, Pa, U,
Np, etc. and metalloids such as B, P, As, ete.
Halonium salts included by formula I are, for
example,
IH3
I BF4 I PF6
~+_ ~
I BF4 I SbF6
2 ~
~ I BF4
. ~
There is provided by the present invention, poly-
merizable compositions comprising:
(A) a monomeric or prepolymeric cationically
polymerizable organic material selected from
vinyl organic monomers, vinyl organic
prepolymers, cyclic organie ethers, eyclic
organic esters, cyclic organic sulfides,
- 15 organosilicon cyclics and cyclic amines, and
-- 5 --
~Z7~ 6
RD-7373
(B) an e~fective amount of a radiation Sensiti~Je
aromatic halonium salt capable of effectin~
the polymerization of (A) by release of a
Lewis Acid catalyst when exposed to radiant
eneryy.
~he halonium salts of formula I are well knor,ln
and can be made by the procedures described by O.A.
Ptitsyna, M.E. Pudecva, et al, Dokl, Adad Nauk, SSSR, 163,
383 (1965); Dokl, Chem., 163, 671 (1965). F. Marshall
Beringer, M. Drexler, E.M. Gindler, J. Am. Chem. Soc., 75,
2705 (1953~. 3. Collette, D. McGreer, R. Craw~ord, et al,
J. Am. Chem. Soc. 78, 3819 (1956).
Included by the vinyl organic monomers which can
be used in the practice o~ the invention to make
polymerizable compositions which are convertible to
thermoplastic polymers are, for example, styrene, vinyl
acetamide, ~-methyl styrene, isobutyl vinylether, n-octyl
vinylether, acrolein, 1,1-diphenylethylene, ~-pinene; vinyl
arenes such as 4-vinyl biphenyl, 1-vinyl pyrene, 2-vinyl
fluorene, acenaphthylene, 1 and 2-vinyl naphthylene;
9-vinyl carbazole, vinyl pyrrolidone, 3-methyl-1-butene;
vinyl cycloaliphatics such as vinylcyclohexane,
vinylcyclopropane, 1-phenylvinylcyclopropane; dienes such
as isobutylene, isoprene, butadiene, 1,4-pentadiene, etc.
Some of the vinyl organic prepolymers ~Ihich can be
used to make the polymerizable compositions of the present
~274~ RD-7'73
invention ar2, for example~ CH2=CH-0-(CH2-CH20)n-CH=CH2,
where n ls a positive integer having a value up to about
1000 or hiyher; multi~functional vinylethers, such as 1,2,~-
propane trivinyl ether, trimethylolpropane trivinyl ether,
prepolymers having the formula,
CH=CH2 n
and 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
potting resins, crosslinked coatings, printing inks and other
applications typical of thermosetting or network resins.
A further category of the organic materials which
can be used to make the polymerizable compositions are cyclic
ethers which are convertible to thermoplastics~ Included by
such cyclic ethers are, for example, any monomeric, dimeric
or oligomeric or polymeric epoxy material containing one or a
plurality of epoxy functional groups. For example, those
resins which result from the reaction of bisphenol-A (4,4l_
isopropylidenediphenol) and epichlorohydrin, or by the reaction
of low molecular weight phenol-formaldehyde resins (Novolak
resins) 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-vinylcyclo-
hexene dioxide, limonene dioxide, 1,2 cyclohexene oxide,
glycidyl acrylate, ~ycidyl methacrylate, styrene oxide, allyl
glycidyl ether, etc., may be added as viscosity modifying agents
,.
_.1~
~27~ P.~-7373
In addition, the range of these compounds can be extended to
include polymeric materials containing terminal or pendant
epoxy groups. Examples of these compounds are vinyl
copolymers containing glycidyl acrylate or methacrylate a3
one of the comonomers. Other classes of epoxy con-taining
pol~mers amenable to cure using the above catalysts are
epoxy siloxane resins, epoxy-polyurethanes and epoxy-
polyesters. Such polymers usually have epoxy functional
groups at the ends of their chains. Epoxy-siloxane resins
and method fo- making are more particularly shown by E P
Plueddemann and G. Fanger, J. Am. Chem. Soc~ 81 632-5 (1959)o
As described in the literature, epoxy resins can also be
modified in a number of standard ways such as reactions with
amines, carboxylic acids, thiols, phenols, alcohols, etc. as
shown in U.S. patents 2,935,488 issued May 3, 1960; 3,235,620
issued February 15, 1966; 3,369,055 issued February 13, 1968:
3,379,653 issued April 23, 1968; 3,398,211 issued August 20,
1968 3,403,199 issued September 24, 1968; 3,563,850 issued
February 16, 1971; 3,567,797 issued March 2, 1971; 3,677,995
issued July 18, 1972, etc. Further examples of epoxy resins
which can be used are shown in the Encyclopedia of Polymer
Science and Technology, Vol. 6, 1967, Interscience Publishers,
~ew York, pp 209-271. The term epoxy resin as hereinafter
employed may signify both curable epoxy polymers, prepolymers
and monomers or mixtures thereof. Also included as cyclic
ether~ are oxetanes such as 3,3-bis-chloromethyloxetane alkoxy-
oxetanes as shown by Schroeter U~S. Patent 3,673,216 issued
June 27, 1972, assigned to the same assignee as the present
invention; oxolanes such as tetrahydrofuran, oxepanes, oxygen
containing spiro compounds, trioxane, dioxolane, etc.
~7~ RD-7-'7~
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-trimethylazetidine and organo-
silicone cyclics, for example, materials included b~ the
. ~, ., ~
_-- R2 S iO --_
.
m
where R" can be the same or different monovalent organic
radicals such as methyl or phenyl and m is an integer equal
to 3 -to 8 inclusive. An example of an organosilicon cyclic
is hexamethyl trisilo~ane, octamethyl tetrasiloxane, etc.
The products made in accordance with the present invention are
high molecular weight oils and gums~
The curable compos itions of the present invention
can be made by blending the polymerizable organic material
with an effective amount of the halonium salt. The resulting
curable composition which can be in the form of a varnish
having a viscosity of from 1 centipoise to 100,000 centipoises
at 25C can be applied to a variety of substrates by conventional
means and cured to the tack-free state within 1 second or less
to 10 minutes or moreO In other instances, for example, where
a solid epoxy resin is employed, the curable composition can
be a free flowing powder4
In particular instances, depending upon the
C~ 9~np~
~- of the halonium salt with the organic material,
the halonium salt can be dissolved or dispersed in an organic
solvent such as nitromethane, acetonitrile, methylene chloride,
etcO, prior to its incorporation into the organic material.
~ere the polymerizable oryanic material is a solid, e.g.
c~_
~ D-7'7-,
certain of the higher molecular T~eight bisphenol Of novola7
based epoxy resins, incorpora-tion of the onium salt may b~
achieved by dry milliny or rnelt mixing where the melting
point of the resin is suitably low. Experience has sho,m
that the proportlon of halonium salt to organic material can
vary widely inasmuch as the salt i5 substantially inert,
unless activated. Effective results can ~e achieved, for
example, if a proportion oE from 0~1% -to 15% by weight of
halonium salt is employed, based on the weight of polyrnerizable
compositionO Higher or lower amounts can be used, however,
depending upon factors such as the nature of organic material,
intensity of radiation, polymerization time desired, etc.
It has been found that the halonium salt of formula I
also can be generated in situ in the presence of the organic
materlal if desired. For example, an onium salt of the formula,
L (R)a(~ )b X] LY~I
where R, R , X, a and b are as previously defined, and Y is
an anion such as Cl , Br , I , F , ~S04 and N03 , etc. can
be separately or simultaneousLy introduced into the organic
material with a Lewis Acid of the formula,
M'(MQ)
where M and Q are as previously defined and M~ is a metal
cation such as an alkali metal, for example, Na , K , etc.,
alkaline earth, such as Ca , Mg or an organic cation such
as quaternary a~monium, pyridinium, etc~
The curable compositions may contain inactive
ingredients such as inorganic fillers, dyes, pigments, e~tenders,
viscosity control agents, process aids, W-screens, etc. in
amounts of up to 100 parts filler per lO0 of epoxy resin. The
~1.0-
3~ ~7f`~4~i 7~ ' 7,
curable compositions can be applied -to sush substrate3 as
metal, rubber, plastic, molded parts or films, paper, -"ood,
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, decorati.ve and insu~ting coatings,
potting compounds, printing inks, sealants, adhesives,
photoresists~ wire insu~tion, textile coatings, laminates,
impregna-ted tapes, etc.
Polymerization can be achieved by activating the
halonium salt to provide the release of ~he Lewis Acid
catalyst. Activation of the halonium salt can be achieved
by heating the composition at a temperature in the range of
from 150 C to 250C~ Preferably, polymerization can be
achieved by exposing the composition to radiant energy such
as electron beam or ultraviolet light. Electron beam cure
can be effected at an accelerator voltage of from about 100
to 1000 KVo Polymerizati.on is preferably achieved by the
use of UV irradiation having a wavelength of from 1849 ~
to 4000 ~. The lamp systems used to generate such radiation
can consist of ultraviolet lamps such as from 1 to 50
discharge lamps, for example, xenon, metallic halide,
3 ~74&~
R~-7~73
metallic arc, such as a low, medium or high pressure mercury
vapor discharge lamp, etc. having an operatiny pressure of
-from a few millimeters to about 10 atmospheres, etc., can
be employad~ The lamp~ can include envelopes capable of
transmitting light of a wavelenyth preferably of 2400 ~ to
4000 A~ ~e lamp env~lope can consist of quartz, such as
Spectrocil or Pyrex, etc. Typical lamps which can be
employed for providing ultraviolet radiation are, for example,
medium pressure mercury arcs, such as the GE ~3T7 arc and
the Hanovia 450 W arc lamp. Polymerization may be carried
out with a combination of various lamps, some or all of
which can operate in an inert atmosphere. When using UV
lamps, the irradiation flux in the substrate can be at least
0.01 watts per square inch to effect polymerization of the
organic material within 1 to 20 seconds and permit the cure
to be ca~ried on continuously as, for example, in the curing
of a multifunctional vinyl ether or epoxy resin coated steel
strip, or paper web, to be taken up a- a rate of from 100 to 600
feet per minute. I~e web can be cut to a predetermined width
for use as printed material. A combination of heat and light
may be us~d to cure reactive compositions. Such a combina-
- 12 -
~7~6~
RD-7373
tion of heat and light may serve to reduce the o~erall
curve time.
In order that those skilled in the art will be
better able to practice the invention, the ~ollowing
examples are given by way of illustration and not by T"aI of
limitation. All parts are bv weight.
EXAMPLE 1
A curable mixture was prepared by adding under a
nitrogen atmosphere 0.2 part of diphenyliodonium hexa-
fluorophosphate to 39 parts of tetrahydrofuran. Theresulting mixture was exposed for 10 minutes to ultraviolet
light from a GE H3T7TM lamp. The resulting product was
allowed to stand for 3 hours. A highly viscous product was
obtained. The polymer was then poured into water to
destroy the catalyst and then was ~iltered off and
dissolved in tetrahydrofuran. On pouring the highly
viscous polymer into methanol, a fibrous, tough polymer was
obtained. The polymer was washed with methanol and dryed
to give a pale yellow material having an intrinsic
viscosity of 3.9 dl/g. This indicates a molecular weight
of greater than 350,000. The polymer was pressed into an
exceedingly tough film. It could be heat-pressed to a
particular shape.
The procedure is repeated except a portion of the
mixture is allowed to remain under normal daylight conditions
- 13 -
~,.
RD-7373
for several days at ambient temperature. No chanye in
viscosity is noted.
EXAMPLE 2
A mixture of 0.1 part of diphenyliodonium fluoro-
5 borate and a solution of 13.3 parts o~ N-vinylcarbazole in
39.9 parts of methylene chloride was irradiated for 10 min.
at a distance of 3 inches from a 450 W HanoviaTM lamp.
Irradiation was performed under nitrogen while the mixture
was in a vial. There was observed rapid exothermic poly-
merization of the monomer to give a viscous polymer. Afterstanding in the dark for 3 hours, the polymer was isolated
by pouring it into methanol. There was obtained after
filtering, washing and drying 13.1 parts of a dry, powdery
polymer. Based on method of preparation, the polymer was
polyvinylcarbazole useful as a molding compound.
EXAMPLE 3
Three parts of p-methoxydiphenyliodonium
fluoroborate were added to 97 parts diethyleneglycol
divinyl ether. This blend was thoroughly mixed by stirring
for one hour. Then the sensitized mixture was applied to a
glass plate as a 1 mil coating. Exposure of this
composition to ultraviolet light from an H3T7 lamp at a
distance of four inches for 2-3 seconds in air gave a
completely cured, hard coating which could not be removed
by rubbing with acetone.
, ~,.
~7~6
RD-7373
A portion of the above sensitized mix-ture was
combined with 2 parts by weight Cabosil~ M-5 silica filler
and knife coated to provide a 2 mil coating. The film r"as
cured as before and required 3 seconds irradiation to be
converted to a hard translucent coating.
EXAMPLE 4
A mixture of 0.32 part of diphenyliodonium
chloride, 10 parts of ethylene glycol divinyl ether and
0.21 part of NaAsF6 was heated under sealed condi-tions for
5 hours at 50C. All suspended salts were then allowed to
settle and the clear solution was knife coated onto a 3 in
x 6 in steel panel to provide a 0.2 mil coating. Cure was
performed as in Example 3. Three seconds were required to
give a highly cured, acetone resistant coating.
EXAMPLE 5
There were added 0.3 part di-p-tolyliodonium
fluoroborate and 0.4 part carbon black to 15 parts tri-
methylolpropane trivinyl ether. The mixture was agit~ted
for 3 hours in a ball mill and then applied to white print
paper. Exposure of the treated paper to ultraviolet light
from an H3T7 lamp at a distance of 3 inches cured the ink
in 1-2 seconds.
- 15 -
""." ~
'~.
12~ 6
RD-7373
EXAMPLE 6
There was added 0.1 part of p-methoxyphenyl-
phenyliodonium hexafluorophosphate to a mixture of 6 parts
hexamethylcyclotrisiloxane and ~ parts octamethyltetra-
siloxane. The mixture of monomers and sensitizer wassealed under nitrogen. The mixture was then placed 3
inches from a Hanovia 450 wat~ lamp and irradiated for 10
minutes to ac~ivate the catalyst. APter allowing the
mixture to stand for 16 hours during which the contents
became very viscous, the product was poured into methanol.
Based on method of preparation, the product was a
polydimethyl siloxane oil. It was recovered by decanting
- the methanol layer, washing with more methanol and then
drying in vacuo at 60C. The polydimethyl siloxane oil was
useful for imparting improved surface characteristics to
fibrous substrates.
EXAMPLE 7
A mixture was prepared composed of 2% diphenyl-
iodonium tetrafluoroborate, 97.5% ethyleneglycol divinyl
ether and 0.5% of a surface active agent. The mixture was
stirred until homogeneous and then coated onto a 3 in x 6 in
steel panel using a 0.2 mil drawblade. After exposing the
panel for a period of l second to ultraviolet radiation, the
film became hard. The film could not be removed by rubbing
with acetone nor was it affected by immersion in boiling
water for one hour.
- 16 -
~L~7~
RD-7373
EXAMPLE 8
A mixture of 0.26 part of 4-methoxydiphenyl-
iodonium fluoroborate, 28.8 parts of freshly distilled
stvrene and 13 parts of methylene chloride was flushed ,Jith
nitrogen and sealed. The mixture was exposed six minutes to
a 450 watt Hanovia lamp. Rapid polymerization took place
and the polymeri~ation product was allowed to stand in the
dark for 2 hours. A highly viscous reaction product was
obtained which was poured into me-thanol and the solid
product was filtered and washed. The product was dried in a
vacuum oven. There was obtained 25.7 g of product. Based
on method of preparation, the product was polystyrene.
EXAMPLE 9
A mixture of 22.8 parts of recrystallized
acenaphthalene, 0.23 part of 4-methoxydiphenyliodonium
fluoroborate and 58.6 parts of methylene chloride was purged
with nitrogen and sealed. It was then irradiated for 8
hours in accordance with Example 8. A powdery tan
precipitate of polyacenaphthalene was obtained on pouring
the solution into methanol. After drying overnight in a
vacuum oven at 60C there was obtained 22.2 parts of
polymer.
EXAMPLE 10
A mixture of 11.4 parts of ~-methylstyrene, 0.11
part of 4-methoxydiphenyliodonium fluoroborate and 13 parts
- 17 -
5~
~27~64~ 7~r3-7373
of methylene chloride was flushed with nitroyen and sealed
r~hile using a methanol dry ice bath, the mixture ~"as irra~1iated
as in Example 8. The resulting highly viscous pol~n~r
solution was quenched by adding a small amount of methanol
and the polymer isolated by pouring the solution into a
large amount of methanol. After drying, 11 parts of
poly-G~-methylstyrene were obtained.
EXAMPLE 11
A solution of diethyleneglycol divinyl ether
containing 2% by weight 4-methoxydiphenyliodonium fluoro-
borate was coated onto a 3 in x 6 in steel plate. A per-fora-ted
mask was placed over the coating and this assembly was exposed
to ultraviolet light using a GE H3T7 medium pressure mercury
arc lamp at a distance of four inches. After a 5 second
exposure, the mask was removed and the plate was washed with
i-propanol. A clear, raised negative image of the mask was
formed. These results showed that this photo-imaging procedure
was useful in printing plate applications and in printed
circuits for semiconductor devicesO
EXAMPLE 12
There was added a cooled solution of about 100 ml
of acetic anhydride and 70 ml of concentrated sulfuric acid
to a suspension of 100 g of potassium iodate in 100 ml of
acetic anhydride and 90 ml of benzene. During the addition,
the mixture was stirred and maintained below 5C. ~hen the
addition was complete, the reaction mixture was allowed to
warm to room temperature and stirred for 48 hoursO There
was then added 400 ml of distilled water. The aqueous portion
of the reaction mixture was extracted three times ~ith diethyl
ether and petroleum ether to remove unreacted organic materials.
A pale yello~" crystalline product formed upon addition 3~
1274~6 RJ~--7 ~7 -~
ammonium chloride to the aqueous reaction mixture. m ere ~,1a,
obtained a 48% yield o-E diphenyliodonium chloride ha~ing a
m~p. of 180-185C. The pure salt had a m~p~ of 22,3-229C~
A mixture of 20 y of moist, freshly prepared Ag20,
10 ml of water and 31.6 g of diphenyliodonium chloride ~,7as
ground together in a slurryv The wet mixture r,~as filtered
and washed with water to produce 360 ml of filtrate. The
filtrate was cooled until a substantial amount of the solution
had frozen~ There was slowly added 25 ml 45-50% ~BF4 cooled
to -15 C. The cold solution was stirred and allowed to warm
to room temperature. A white crystalline solid separated and
was collected by filtration~ There was obtained a 60~/~ yield
of diphenyliodonium fluoroborate, m.p. 136 C when the solid
was dried overnight in vacuo at 60 C~
A curable composition was prepared by dissolving
0~05 part of diphenyliodonium tetrafluoroborate in a small
amount of acetonitrile and mixing the resulting solution in
5 parts of 4-vinylcyclohexene dioxide~
The viscosity of the resulting curable composition
was found to be initially about 6 centipoises at 25 C. It
did not change substantially after several months exposure
under normal room lighting.
A portion of the curable compositions was applied
as a 0~1 mil film onto a steel strip~ The treated steel
surface was exposed 15 seconds to the ultraviolet radiation
of an H3T7 lamp at a distance of 2 inches. A clear tack-free
film was formed which showed no si~ns of bubbles or other
imperfectionsO
The above treated slrip was then immersed in lOC
30 hydrocarbon oil for 48 hours at 120 C to determine its
hydrolytic stahility in accordance with IF'T test AST~I D971-50
-19-
~ ~74~ p~-7~7'
Interfacial Tension of Oil Against Water shown on page 722
of the 1970 Annual Book of ASTM Standards, part 17 ~Movember~.
~le initial reading of the oil was about 39.0 dynes/cm.
After the test thP oil showed an inter~acial -ten~ion
reading of 38. In order to pass, a reading o at least 30
is required.
EXAMPLE 13
The procedure of Example 1 was repeated for pre-
paring an aromatic halonium salt using diphenyliodonium
chloride. In this preparation, fluoroboric acid was
replaced by 25 ml (60~d) hexafluorophosphoric acidO T'nere
was obtained a 74% yield of diphenyliodonium hexafluoro-
phosphate having a m.p. of 139-141 C.
A curable composition was prepared following the
same procedure as Example 1. Comparable results were
achieved with respect to its ability to resist change in
viscosity over an extended period of time under normal
atmospheric conditions. Xn addition, satisfactory IFT
values were also obtained,
EXAMPLE 14
A cuxable composition was prepared using a 40:60
-20-
P~J~-77
solution Gf 4-vinylcyclohene dioxide and a novolak epoxy
resin and adding 2% by weight of diphenyliodonium tetra-
fluoroborake in a small amount of nitromethane.
The curable composition was spread on a glass
plate~ A mask was then used to cover the treated glass~
After irradiation under an H3T7 lamp for 1.5 minutes, the
glass was washed with isopropanol. The unexposed portions
were washed completely away leaving a negative image of the
mask~ When the same procedure is repeated using a steel
plate as the substrate, the product is useful for the
fabrication of printing plates.
EXAMPLE 15
Several curable compositions were prepared in
accordance with the procedure shown in Example l using 4-
vinylcyclohexene dioxide and about 3% by weight of the
halonium salt. Various cure times were experienced when the
compositions were applied onto a glass substrate and cured
at a distance of four inches from a ~E H3T7 lamp. The
following shows the halonium salt used~ its mOp. and the
cure times.
~21-
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EXAMPLE 16
To 10 g limonene dioxide were added 0.32 g
diphenyliodonium chloride and 0.21 g sodium
hexafluoroarsenate. This mixture was heated Eor 20 minutes
at 50C to achieve metathesis. The salts were allowed to
settle and thP clear supernatent liquid was drawn off. The
sensitized epoxy compound was applied to a steel strip to a
thickness of 2 mil and exposed to UV light as described
above, Cure took place in 30 seconds. A tough film having
good adhesion to the steel plate was obtained.
EXAMPLE 17
Three parts of diphenyliodonium fluoroborate were
ground to a fine powder and tumbled for 30 minutes with 97
parts of Reichhold Epotu ~ 37-834 powder coating resin. The
powder blend was then electrostatically sprayed onto 3 in x
6 in steel samples to form a 2 mil coating using a GEMA
model 171 spray gun. Subsequently, the samples were heated
briefly to 150C to fuse the powder and then exposed while
hot to a GE H3T7 medium pressury mercury arc lamp at a
distance of 3 inches. Cured samples were obtained after 30
seconds exposure.
EXAMPLE 18
Three parts by weight of di-p-tolyl iodonium
fluoroborate were added to 97 parts of (3,4 epoxycyclohexyl)-
methyl-3,4-epoxycyclohexanecarboxylate. The epoxy resin
'~jf !
~ 27 4 ~ .D - 7 37 3
was then used to irnpregnate a 1 inch woven glass tape,
After winding two turns of the tape onto a 4 in diameter
drum, the tape was cured to a rigid glass band by rotating
the drum under a GE H3T7 lamp at a distance of 4 inches
for 2 minutes, The banding tapes thus prepared can be used
as restraining bands in moto~s and generators,
The above resin was used to impregnate woven
glass cloth, Two 6 in x 6 in squares of the glass cloth
were stacked on top of one another and cured for 1 mir~.te
on each side. A rigid composite was obtained which is use-
ful for circuit board applications,
A portion of the above mixture was used to impreg-
nate glass roving. The treaked glass was then wound onto
a 3 in dia, drum to a thickness of about 5 mils, The drum
was then rotated beneath a GE H3T7 lamp at a distance of
3 inches for 5 minutes, A measurement of ~he intensity of
the lamp sho~ed that it was approximately 200 watts/sq,
inch, When the cured winding was removed from the drum, it
was rigid and fully cured. A kypical use for such a cured
winding is as a spool for electrically conducting wire.
EXAMPLE 19
A mixture was prepared consisting of 14,5 g (0,25
mole) glycidyl allyl ether, 10 mg, t-butyl-catechol, and
3 drops chloroplatinic ac:id in octyl alcohol, The reaction
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~ ~'7~ P~D-7~73
mixture was hea~ed to 50C in a water bath and then 13,0 g
of a polydimethyl siloxane resin containing 0,89% by ~7eigh~
Si H groups was added dropwise by means of a dropping
funnel, Ir~unediate exothermic reaction took place with the
ternperature rising to 65C, Reaction proceeded smoothly
at this temperature giving a clear resin,
Three parts by weight of 4-methoxydiphenyl-
iodonium fluoroborate dissolved in a small amount of
methylene chLoricle was added to 97 parts of the above~sllicon~
epoxy resin, A 2 mil film of the sensitized resin was
drawn on a steel plate and then exposed to W light from a
GE H3T7 lamp at a distance of six inches, The film was
tack-free within 10-15 seconds, A small amount of silica
was added to Lhe sensitized resin to produce a thixotropic
mixture and Lhe resin cured as described previously, A
tough, rubbery coating resulted,
EXAMPLE 20
~ solutiorl o~ ~ parts of 4-metho~ydiphenylio~onium
fluoroborate dissolved in 20 parts of 4-vinyl-cyclollexene
dioxide was added to 80 parts of a glycidyl methacrylate-
methyl methacrylate copolymer having a molecular ~eight of
8,500 and a glycidyl acrylate content of 5% by weight,
This mixture ~as mixed by rolling it in a glass bottle on
a ball mill overn:igllt, The viscous solution was knife
~25-
P~-7373
coated onto a glass plate to give a 2 mil film wh iCIl '~JIlell
irradiated at a distance of six inches from a GE ~{317 lamp,
gave a clear hard coating in 10 seconds. The film was
highly crosslinked and in.;~Luble in all common solvents.
E~AMPLE 21
Three parts of diphenyliodonium hexafluoro-
arsenate were dissolved in 6 7 parts of methylene chloride
and the solution added to 97 parts glycidyl acrylate. A 3
part aliquot of this highly fluid mixture was placed in an
aluminum cup ancl thell exposed to the ultraviolet Lrr.~diation
of a H3T7 lamp using a water filter. Th~ cure time was 15
seconds. Subsequent analysis showed that the conversion
to polymer was greater than 95%. A hard glossy resin was
obtained
EX~MPLE 22
A blend was prepared using equal parts of 4-vinyl-
cyclohexene dioxide and (3,4-epoxycyclohexyl)methyl-3,4-
epoxycyclollexanccarboxylate ~o this blend were added four
parts of diphenyliodonium fluoroborate. An aliquot of the
above sensitized resin was spread onto a sheet of Lexan~`
polycarbonate using a draw-down blade to give a 0.5 mil film.
The film was cured as described in Example 3 for 20 seconds
giving a clear hard coating which provides mar and solvent
resistance for the substrate polymer.
26-
~7~ RD-737~
EXAMPLE 23
A mixture of 50 parts bisphenol-A-diglycidyl ether
and 50 parts (3,4-epoxy-cyclohexyl)rnethyl-3,4-epoxycyclo-
hexanecarboxylate was stirred until hornogeneous and then 3
parts by weight diphenyliodonium hexafluoroantimonate in a
small amount of methylene ch].oxide was added and the
solution thoroughly mixed, A portion of the above sensi-
tized solu~ion was coated onto a s~eel plate using a 0,2
mil drawbar. ~he pla~e ~as then irradiated for 10 seconds
using a ~E 113T7 mercury arc lamp at a distance of six
inches, The completely cured, hard, glossy film had
excellent adhesion to the steel and could not be removed
by rubbing it with acetone,
EXAMPLE 24
A blend of epoxy resins consisting of 50 parts
4-vinylcyclohexane dioxide, 40 parts of a novolak-epoxy
resin having an epoxy equivalent weigh~ of 172-178 and 10
parts n decylglycidyl c~;ler were thoroughly mixed togctller. A
100 part allquot was taken and 1 p~rt diphenyllodonium hex.~l~oro-
phosphate was added and the resultlng mixture stirred until
the catalyst had dissolved, When the above mixture was
coated onto a 3 in x 6 in panel and then exposed to a 450
wat~ medium pressure mercury arc lamp at a distance of 3
inches, a glossy, dry coating was obtained in 3 seconds.
--27--
~7g~9L6
P.D-7~73
The coating withstood attack by hot boiling ~7a~er fo-r fo~l-r
hours and could not be removed by rubbing ~lith
acetone,
EXAMpLE25
-
There was added 1 g of di-p-tolyliodoniurn fluoro-
borate to a mixture of 40 g limonene dioxide and 10 g of a
solid multifunctional aromatic glycidyl ether having an epoxy
equivalent weight of 210-240, The mixture was stirred at
50C for 1 hour to produce a homogeneous solution of the--'
components. When the mlxture was coated onto a glass plate
using a 0.5 mil drawbar, a hard, adherent, cured film was
produced by irradiating the sample for 5 seconds at a dis-
tance of 3 inches from a GE H3T7 lamp which has an intensity
of 200 watts/sq, inch.
r
EXAMPLE 26
There was added 0,2 part p-methoxydiphenyliodonium
fluoroborate in 2 parts 4-vinylcyclohcxene dioxide to 10
pa~s of an epoxidized butadiene resin. After mlxlng, a 1 mil
coating of the resulting mixture wa~ applied onto a 1/16
inch thick glass plate, Another plate of glass was placed
on top of the first and thls assembly exposed to a GE H3T7
medium pressure mercury arc lamp having an intensity of
200 watts/sq. in. at a distance of 3 inches. The total
time of exposure was 1 minute. The glass plates were
-28-
~ ~ 4 ~ RD-737
permanently bonded toyether and the glass laminate could 'De
used as a shatterproof windshield for automobiles.
~L.~
A mixture was prepared consisting of by weight
67% of a novolak~epoxy resin haviny an epoxy equivalent
weight of 172~178, 33% 4-vinylcyclo~exene dioxide, 0.S~/~ of
a sur~ace active agent, and 1% diphenyliodonium hexafluoro-
arsenate. me mixture was applied as a 0~1 mil film to
3 in x 6 in steel plates. The treated plates were exposed
for 20 seconds at a distance of 4 inches from a GE ~3T7
medium pressure mercury arc lamp. Panels were subsequently
immersed for 5 hrs. at room temperature in methylene
chloride, others were immersed for 4 hours in acetone, In
all cases, no visible signs of attack on the coating by these
agents were observed. The panels were baked for 1 hour at
160 C, then tests were run separately in boiling 5% KOH
solution for 30 minutes and in boiling distilled water for
4 hours. At the end of these tests, the coatings were
intact and showed no signs of degradation.
~0 Although the above examples are limited to only a
few of the very many polymerizable compositions and uses
thereof which are included within the scope of the present
invention, it should be understood that the present invention
is intended to cover a much broader class o polymerizable
compositions such as a mi~ture of the halonium salt and a
cyclic organic sulfide and uses thereof. Those skilled in
the art would also know that the polymerizable compositions
also cover the use of onium polymers containing halonium
functionality as part of the polymer backbone or in a pendant
position.
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