CA2031114A1

CA2031114A1 - Alkenyl ethers and radiation curable compositions

Info

Publication number: CA2031114A1
Application number: CA002031114A
Authority: CA
Inventors: Fulvio J. Vara; James A. Dougherty; Jeffrey S. Plotkin; Kolazi S. Narayanan; Paul D. Taylor
Original assignee: GAF Chemicals Corp
Current assignee: GAF Chemicals Corp
Priority date: 1990-01-26
Filing date: 1990-11-29
Publication date: 1991-07-27
Also published as: AU6893691A; WO1991011467A1

Abstract

ALKENYL ETHERS AND RADIATION CURABLE COMPOSITIONS

ABSTRACT

The invention relates to alk-1-enyl ether silicates having the formula (I) and a process for making same, [X]4-nSi[OR1OCH=CH-R2]n wherein X is halogen or -OR wherein R is lower alkyl or a mixture of halogen and OR, a mixture of OR and hydrogen or a mixture of halogen and hydrogen;

R1 contains from 1 to 8 carbon atoms and is alkylene, alkenylene, alkynylene, optionally alkoxylated with up to 20 units of wherein Y is hydrogen or methyl and R2 is each hydrogen or lower alkyl and n has a value of from 1 to 4;
and polyfunctional alkenyl ether having the formula (II) A[(CH2O)m(Z)rCH=CHR]n wherein A is a carbon atom, -OCH=CHR or [C1 to C10 alkyl]4-n; R is C1 to C6 alkyl; Z is C2 to C8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and at least one of r and m has a positive value; n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is -OCH=CHR, n has a value of 2 or 3 when A is [C1 to C10 alkyl]4-n and n has a value of 4 when A is carbon.

This invention also relates to a radiation curable cross linkable compositions containing (a) from about 0.1 to about 5 wt. % of an initiator containing at least 25%
cationic initiator, (b) from about o to about 60 wt. % of a polymerizable vinyl ether, epoxide, vinyloxy alkyl urethane or acrylate and (c) from about 35 to about 99.9% wt. % of an ether of formula II.

Description

2~3~

ALKENYL ETHERS AND RADIATION CURABLE COMPOSITIONS

According to this invention there i5 provided an alk-~-enyl ether silicate having the formula (I) [X]4_nSi[ORlocH=cH-R2]n ' ~ .
wherein X i~ halogen, -OR wherein R is lower alkyl, a mixture of halogen and -OR, a mixture of -OR and hydrogen :
or a mixture of halogen and hydrogen;

Rl contains from 1 to 8 carbon atoms and is alkylene, alkenylene, alkynylene, optionally alkoxylated ?
with up to 20 units of - (CH2cHO) -wherein Y is hydrogen or methyl, R2 is hydrogen or lower alkyl and n has a value of from 1 to 4. ~ .

Of the above compounds, those mixtures wherein X ;
contains -OR and wherein R2 is hydrogen atoms, are preferred and products wherein n has a value of at least 2 are most preferred. Mixtures of the alk-1-enyl ether ~ilicates O:e the present invention can contain varying amounts of 2 to 4 components where n has a value of 1,2,3 and/or 4. Preferred mixtures are those wherein the tris(vinyloxyalkylene) alkyl orthosilicate i5 present.

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The products of Formula (I) are prepared according to the reaction illustrated by the equation:

SitX]4 ~ n HORlOCH~CEiR2 ~ ~x]4-nsitoRlocH~cHR;2]n + n XH

~ilicat~ hydro~ alkenyl ether produ~t by-product. ;~

Suitable examples of silicate reactan~s include tetrachlorosilane, tetrafluorosilane, tetrabromosilane, tetramethyl orthosilicate, tetrabutyl orthosilicate, tetraethyl orthosilicate, tetrapropylyl orthosilicate, diethyl orthosilicate, dipropyl orthosilicate, tributyl : ~ :
orthosilicate, triethyl orthosilicate, tribromoethyl orthosilicate, dichlorodiethyl orthosilicate.
Representative hydroxy vinyl ethers which are suitably employed in the reaction include hydroxybutyl ~` .
vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl ::
prop-1-enyl ether, hydroxyethyl but-1-enyl ether, hydroxyhexyl vinyl ether, hydroxyethyl 2-butyl hex-l-enyl ether, hydroxy butenyl vinyl ether, hydroxybutynyl vinyl ether, hydroxybutynyl-prop-1-enyl ether, hydroxypropynyl vinyl ether, hydroxybutyl 3-methylprop-1-enyl ether, the vinyl ether of di-hydroxymethyl cyclohexane and alkoxylated vinyl ether derivatives of the above having the formula HORl- ( OCHCH2 ) mOCH--CHR2 where m has a value of from 1 to 20, preferably from 1 to 8 and R1, Y and R2 are as defined above.

- 2 0 3.~

The mole ratio of silicate to hydroxylated alkenyl ether depends on the number of terminal alkenyl groups desired in the product and the number of halo and or OR
groups in the silicate reactant and is as close to stoichiometry as is conveniently maintained; although up to a 10:1 excess of silicate reactant over said stoichiometric amount is within the scope of this invention.
The reaction is carried out under anhydrous conditions in the presence of from about 0.01 to about 10 wt. %, preferably from about 0.1 to about 5%, of a base catalyst based on the alkenyl ether reactant. Catalysts such as sodium or potassium metals, sodium or potassium hydroxides, hydrides, alkoxides or salts of the hydroxy alkenyl ether as well as titanium alkoxide are suitably employed. When halogenated silicates are employed, the -;
addition of a base is required during the reaction to ~
neutralize any hydrogen halide which is generated as ;
by-product. Suitable bases include sodium hydroxide, potassium hydroxide, sodium or potassium alkoxides, pyridine or basic pyridine derivatives, ammonia and amines such as trimethyl amine, tripropylamine and the like.
The reaction mixture may also be affected in up to 90%, pre~erably not more than 50% suitable inert solvent such as toluene benzene, methyl ethyl ketone, N-methyl pyrrolidone, tetrahydrofuran, ethyl acetate, acetonitrile, and the like. Preferred inert solvents are those having a boiling point below that of the desired product.
Generally, the reaction is carried out at a temperature between about 50 and about 200C. for a period of from about 5 to about 48 hours under from ambient pressure up to about 500 psi. Preferred reaction parameters include a ten~perature of between about 100 and about 120C., a reaction time of from about 10 to 20 hours and a pressure from atmospheric to about 50 psi.

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High conversion to product is achieved in the present reaction although a product mixture of mono and poly substituted silicates is usually obtained. Individual products can be separated by fractional distillation if desired. The crude product is separated from base catalyst by usual methods such as extraction and filtration, and from solven*, by evaporation under reduced pressure.
A major advantage of the present products is that they are rapidly curable at ambient temperatures by W and visible light or other sources of radiation such as an electron beam, x-ray, laser emissions and the like. They are also reactive diluents for highly viscous coa~ing materials, such as acrylates, vinyl ethers, epoxides, and non-reactive resins, etc., to promote rapid curing and strong bonding to substrate surfaces. From about 1 to about 60 wt. %, preferably from about 1 to about 30 wt. %, of the present alk-1-enyl ether silicates are added to said acrylates, epoxides and/or vinyl ethers to improve their curing properties.
In accordance with another aspect of this invention there is provided a radiation curable, cross linkable composition containing (a) from about 0~1 to about 5 wt. % of an initiator containing at least 25% of a cationic initiator, (b) from about 0 to about 60 wt. % of one or more polymerizable components of the group of a vinyl ether, epoxide, acrylate or a vinyloxy alkyl urethane and (c) from about 35 to about 99.9% wt. % of an aliphatic polyfunctional alkenyl ether having the formula (II) A[(CH2O)m(Z)rcH=cHR]n : : . : . ~. .

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wherein A is a carbon atom, -OOEI=CHR or [C1 to C10 alkyl]4_n; R is C1 to C6 alkyl; Z is C2 to C8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and at least one of r and m has a positive value; n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is -OCH=CHR, n has a value of 2 3 when A is [C1 to Cl0 alkyl]4-n and n has a value of 4 when A is carbon. ~-', Of the above polyfunctional alkenyl ether compounds, those wherein R is methyl; A is -OCH=CH(lower alkyl), [lower alkyl]4_n or carbon are preferred. ~ -Also, when the present alkenyl ether is asymetrical, the compound most preferably contains at least 35% of the cis isomer with respect to the trans isomer.
The most preferred compositions are those containing between about 20% and about 50% of component (b) and between about 50% and about 80% of component (c) where R is methyl.
The present polyfunctional alkenyl, preferably propenyl, ether compounds of Formula (II) are homopolymerizable resins independently useful as protective coatings and are also effec~ive cross-linking agents for polymerizable vinyl ethers having at least 6 carbon atoms or epoxides such as the divinyl ethers of the bis(hydroxyethyl) ether of bisphenol A, the divinyl ether of triethylene glycol, the divinyl ether of ?
dimethylolcyclohexane, vinyloxyalkyl urethanes, e.g.
divinyloxybutyl urethane oligomers, the diglycidyl ether of bisphenol A and its oligomers, bisphenol A epoxy acrylate and its oligomers, 3,4-epoxycyclohexyl methyl-3',4'-epoxycyclohexane carboxylate, the ethers disclosed in U.S. patents 4,388,450; 4,749,807; 4,775,732 and 4,751,271 and corresponding alkoxylated compounds and : , : : .. . ., - ~
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similar comonomers in monomeric or oligomeric form having a number average molecular weight up to about 5,000 or mixtures of said comonomers and/or copolymers. Such monomeric or polymeric vinyl ethers, epoxidas, acrylates or urethanes can be reacted with the polyfunctional alkenyl ethers of this invention to form a cross-linked copolymeric product having a high cross-linked density and ~xtremely high resistance to abrasion and chemical attack.
As stated above, the present polyfunctional alkenyl ethers, particularly the prop-1-enyl ethers, are homopolymerizable forming an exceedingly branched structure. As such, these agents can be used as rigid coatings on substrates which require an exceptionally high strength, resistance to abrasion and solvent attack.
Substrates on which the copolymerized or homopolymerized agent is suitably coated include metal, wood, ceramic, plastic, leather, paper, glass and the like. The present composition is coated on the substrate by any convenient and conventional technique in the desired thickness, usually in a thickness of between about 0.1 to about 5 ;~
mils.
Instant alkenyl ethers having the structure C~CH20(Z)rCH=CHR]4 produce homopolymers and copolymers which are totally etheric in composition and which have greatly increased surface substantivity and other advan~ages derived from their poly etheric nature, such as high UV resistance and the ability to form hydrogels on exposure to water~
As cross-linking agents, the alkenyl ethers of this invention can be admixed with the above acrylate, urethane, epoxide or vinyl ether monomers or their oligomeric counterparts to effect cross-linking in the presence of a cationic initiator, such as a triphenyl sulfonium salt of phosphorous hexafluoride, diphenyl iodonium salt, a mixture of aromatic complex salts of ~ ' ' : :' -. ~ . : ~ . : ` .

~- 2~3111~

hutyrolactone, a phenyl onium salt or an aryl alkyl onium salt, etc. The initiators suitable to e~fect polym~rization reactions of the present invention include the above named cationic initiators which can be employed alone or in admixture with a free radical initiator to provide a hybrid system. Suitable free radical initiators include 1-hydrocyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propan-1-one, 2,2-dichloro-1-(4-phenoxy- phenyl) ethanone and the like.
When initiator mixtures are employed, the free radical component can comprise up to 75~, preferably between about 30 and about 70%, of the cationic initiator component. A `
particularly preferred initiator mixture includes between about 30 wt. % and about 40 wt. % of said butyrolactone and between about 60 and about 70% of said ketone. The present initiator mixtures are recommended for blends of (b) and (c) where component (b) contains an acrylate. The total amount of initiator employed is generally between about 0.1 and about 5 wt. % with respect to reactant or reactants.
In accordance with this invention, one or more of the present aliphatic aikenyl ethers can be employed or blended with one or more of the polymerizable epoxides, vinyl ethers, acrylates or vinyloxy alkyl urethanes, thus henefiting from the properties of each monomer in the blend. Further, it is found that blends of the present propenyl ether and the divinyl ether of dimethylol cyclohexane enhance solubilization of the cationic initiator. Such blends may contain up to about 60%, preferably from about 20 to about 50% of component (b).
The propenyl ether of component (c) in the present composition, ser~es not only as a reactant, but also as an essential diluent for the vinyl ether and/or epoxide which compounds are highly viscous and difficult to apply as coatings. Thus, the propenyl ether provides a coatable composition without the need for extraneous diluents which in many cases can cause blisters and non-uniformity in the coating product.

---`` 2~311:l~

The compositions of the present invention are cured within a period of up to one second by exposure to a source of radiation, e.g. W light, electron beam, laser emissions, gamma rays etc. Radiation curing in the present cationic system takes place at a fast rate, e.g. from about 200 to about 1,000 feet per minute of coated surface or free formed film, depending upon the intensity and type of radiation employed. W light radiation dosages at room temperature of from about loO to about 1500 milli ~/cm2 are effective and dosages of from about 200 to about 600 milli J/cm2 are preferred. Equivalent dosages for curing are employed when using alternative sources of radiation.
For example, curing with electron beam radiation can be carried out at between about 0.5 and about 20 Mrads, preferably between about 1 and about 10 Mrads. Specific techniques for radiation curing are well known, thus further amplification is not required.
Since the present propenyl ethers are normally liquid, they can be directly mixed with the polymerizable vinyl ether, epoxide or vinyloxy alkyl urethane monomer or oligomer without further conditioning; however, in certain cases where dilution is desired, as in cases where higher molecular weight alkenyl ethers of this invention are employed as component (c) or where the blend provides a highly viscous mixtue, the alkenyl ether can be dissolved in an inert organic solvent such as methyl ethyl ketone, toluene, a hydrocarbon, acetone, an ether or a halogenated compound such as methylene chloride. However, dilution with the above solvents should not exceed 50% when hiyhly resistant coatings are required.
Alternatively, the alkenyl ether monomer or oligomer, in the absence of a comonomer can be applied directly to any of the above substrates and subjected to radiation for curing under the above conditions to form a more highly cross-linked homopolymeric protective coating.

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2~3~ 1~4 It should also be understood that the present compositions can optionally contain minor amounts of conventional adjuvants such as a surfactant e.g. a fluorocarbon surfactant such as a mixture of fluoroaliphatic polymeric esters or a silicane copolymer surfactant or others. It is also to ~e understood that the present compositions can be cured thermally or by radiation induced free radical polymerization; however, an advantage of this invention is ~he ability to cure the compositions by cationically induced radiation which avoids the disadvantages discussed in the foregoing disclosure. It is to be understood however that concurrent free radical and cationic induced polymerization using a mixture of such photoinitiators achieves benefits of this invention and is recommended where component (b) of the composition is an acrylate, e.g. bisphenol A epoxyacrylate.

A one liter round bottomed flask, equipped with a magnetic stirrer, thermometer, water condenser and dry ice trap attached to vacuum, was charged with ~38 g. (3.78 moles) of hydroxybutyl vinyl ether, 196 g. (0.94 mole) of tetraethylorothosilicate and 5 g. of KOH pellets. The flask was heated to 55-60C. for 4 hours, during which time 40 g. of ethanol by-product was taken off. The vacuum was then removed and nitrogen gas was introduced. The flask was then heated to 110C. under ambient pressure. After 12 hours an additional 78 g. of ethanol by-product was removed.
A. The crude reaction product (463 g.) was flash distilled. The main fraction (292 g.) distilling at 100-200C. under 3 mm Hg was found to contain 85% tris (vinyl oxybutyl) ethyl orthosilicate and 15% bis (vinyl oxybutyl) ethyl orthosilicate.
.:

.. . . . . . .

-~` 2~3~1~4 B. A separate 50 g. portion of the crude reaction product was flash distilled at 210C., 1 mm Hg. Analysis of 47 g. o~ the clear, colorless distillate was identified as 81.2% tris (vinyl oxybutyl) ethyl orthosilicate, 15.2%
bis (vinyl oxybutyl) diethyl orthosilicate and 0.8~ tetra (vinyl oxybutyl) orthosilicate.

A 3-necked 100 ml round bottomed flask, equipped with a magnetic stirrer, vertical water condenser connected to vacuum via a trap and nitrogen gas inlet was charged with 25 g. of the above main fraction (Example IA), 40 g.
of hydroxybutyl vinyl ether and 0.5 g. of KOH. The flask was heated to 100C. under a blanket of nitrogen for a period of 5 hours after which the mixture was flash distilled, unreacted material removed at 100C. under 3 mm Hg and the remaining distillate collected. The collected distillate was found to be a mixture of 87% tris (vinyl oxybutyl ethyl) orthosilicate and 10% tetra (vinyl oxybutyl ethyl) orthosilicate.

The main fraction of Example 1 tPart A) was mixed with an equal weight amount of the diglycidyl eth~r of bisphenol A ~EPON-828, Shell), 1 part per hundred parts of resin of a fluorochemical surfactant (FC-430), and 4 parts per hundrad parts of resin of a cationic photoinitiator FX-512 at 50C. until a homogeneous low viscosity liquid was obtained. This mixture was then coated on an aluminum substrate at a thickness of 1.2 mil. The coated surface was exposed for less than 1 second to 400 millijoules/cm2 from a mercury vapor lamp. A tack free, film was produced. Coating properties reported in the following table were determined immediately after W exposure and after a post cure at 177C. for 15 minutes.

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After WAfter Property Exposure Post Cure Pencil Hardness (AST~ D 3363) < 4B F
% Adhesion (ASTM D 3359) 0 80 Double MEK Rubs 39 >100 Reverse Impact - ~10 Mandrel Bend (in.) (ASTM D 3111) 1/4 3/4 The mixture described in Example 3 was coated on a polyester substrate at a thickness of 0.5 mil. The coated surface was exposed to 400 millijoules/cm2 W light for less than 1 second and post cured for 2 hours at 50C.
Chemical resistance was tested by the covered spot test (ASTM D 130~). No attack was observed after 24 hours exposure to 1% H2SO4, 1% NaOH, 10% acetic acid, or distilled water.

The mixture described in Example 3 was coated on an aluminum panel at a thlckness of 0.25 mil. The coated surface was exposed to an electron beam dosage of 3 Mrads for less than 1 second to produce a tack free film. Coating properties reported in the following Table were determined immediately after electron beam exposure and after a post cure at 150C. for 15 minutes.

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TABLE

Property After EB Post Cured Pencil Hardness HB H
% Adhesion 100 100 MEK Double Rubs 2 18 Mandrel E3end 1/~ 1/8 The main fraction of Example 1 part A (2500 gm) was mixed with the divinyl ether of triethylene glycol (25.0 gm~ a bisphenol A epoxy acrylate oligomer (EBECRYL-3700, Radcure Specialties, 50.0 gm), 2 phr*
cationic photoinitiator (FX 512), 2 phr* free radical photoinitiator (IRGACURE-184) and 1 phr* fluorochemical surfactant (FC-430) at 50C. until a homogeneous low viscosity liquid was obtained. this mixture was then coated on a polyester substrate at a thickness of 0.5 mil.
The coated surface was exposed to 400 millijoules/cm2 from a mercury vapor lamp for less than 1 second. A tack free coating with the following properties was produced.

Pencil Hardness 2H
Adhesion 100%
Double MEK Rubs >100 * parts/100 parts resin :. . ~ ,. . . , :

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r- 203~114 The main fraction from Example l part A ~6.20 gm) was mixed with the divinyl ether of triethylene glycol (18.8 gm) and a divinyl ether urethane oligomer ~prepared as described in the Degree Thesis o~ Lennart Carlsson, Dept. of Polymer Technology, The Royal Institute of Technology, Stockholm Sweden, 19~7; 25.0 gm); 4 phr cationic photoinitiator (F~-512), and 1 phr fluorochemical surfactant (FC-430) at 50C. until a homogeneous low viscosity liquid was obtained. This mixture was then coated on a aluminum panel (0.25 mil) and exposed to 400 millijoules/cm2 from a mercury vapor lamp for less than 1 second. A tack free coating with the following properties was produced Pencil Hardness 3B
Mandrel Bend 3/16 inch Double MEK Rubs 11 Into an amber bottle, 50 wt. % of diprop-l-enyl ether of diethylene glycol (70% cis, cis) and 50 wt. % of a diglycidyl ether of bisphenol A were charged and mixed at 50C. ~or 1 hour. To this mixture, 2 parts/hundred parts of the triphenyl sulfonium salt of hexafluorophosphate were added with agitation. The resulting low viscosity liquid was directly coated on an aluminum panel in a thickness of 0.15 mil. The coated substrate was then exposed for less than one second at room temperature to 400 milli J/cm2 radiation from a medium pressure mercury vapor lamp; after which the substrate having a highly crosslinked strongly ad~esive coating* was removed. The coating is resistant to attack by methyl ethyl ketone and is abrasion resistant.

* by Cross Hatch Tape test ASTM 3359 ~'.' ~' ' '` '' ' ' ' ' ` ' ' . ' ' ' . ~ ' . " ' , `` ' ' ' ''. .," ,,, ' ' ' ' ~
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EXAMPLE ~

A two mil thick layer of a mixture of g8 wt. % of the tetraprop-1-enyl ether of pentaerythritol and 2.0 wt.
o~ the triphenyl sulfonium salt of hexafluorophosphate is applied to a polyester substrate. The coated layer is then crosslinked by exposure for about one second at room temperature to electron beam radiation at a dosage of 3 Mrad. The resulting highly crosslinked polymer exhibits strong adhesion, is highly resistant to chemical attack and has superior abrasion resistant properties.

A. Into an amber bottle, 50 grams of substantially pure (>95~) cis, cis dipropenyl ether of triethylene glycol, 50 grams of a diglycidyl ether of bisphenol A, 2 grams of the triphenyl sulfonium salt of hexafluorophosphate and 1 yram fluorocarbon surfactant were charged and thoroughly mixed. The resulting liquid mixture was coated on an aluminum panel with a ~3 coating rod.

B. The above procedure was repeated except that a mixture of 48% cis, cis, 42% cis, trans mixture and 10%
trans, trans was substituted for the cis, cis reactant in A.

C. The procedure in part A was repeated except that 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate was substituted for the dipropenyl ether.

Each of the samples A, B, and C were coated in a thickness of 0.11-0.15 mil on an aluminum panel and then cured by exposure to W light as described in Example 8.
The cured coatings were evaluated and the results are reported in the following Table.

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~31114 ~ 16 -It will be appreciated from the above results that changing the distribution from cis isomer to a cis/trans isomeric mixture did not materially affect the properties of the final coating. Example 10 also demonstrates the high cure speed of the di-propenyl ethers as compared to the di-epoxy compound.

E~AMPLE 11 A. Into an amber bottle, 50 grams of substantially pure (>95%) cis,cis- dipropenyl ether of triethylene glycol, 50 grams of a bisphenol A epoxy acrylate oligomer, 1 gram silicone surfactant, 1 gram cationic photoinitiator and 1.5 gm free radical initiator were charged and mixed at 50C. until homogeneous. The resulting liquid was coated on polyester using a #6 coating rod (approx. 0.5 mil) and cured by an exposure for less than 1 second at room temperature to 400 millijoules/cm2 from a W lamp.

~ . The above procedure A was repeated except that the free radical initiator was omitted from the formulation.

C. The procedure in part A was repeated except that the cationic initiator was omitted from the formulation.

The cured coatings were evaluated immediately after W exposure and the results are reported in the following Table. ~ ~

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Formula A _ B C
Result tac~ freetack free wet Adhesion 100%100% none Double ~EK Rubs >loO 89 none Pencil Hardness F F none This example illustrates the necessity of the cationic photoinitiator and the superior solvent resistance obtained using a cationic and free radical initiator.
, :
EXAMPLE 12 ~
. , - .
A. Example llA is repeated except that the 50 grams of cis,cis- dipropenyl ether of triethylene glycol is replaced with 50 grams of a 1 to 1 wt. % blend of cis,cis- -~
dipropenyl ether of triethylene glycol and the divinyl ether of 1,4-cyclohexane dimethanol.

B. Example llA is repeated except that the 50 grams of cis,cis- dipropenyl ether of triethylene glycol is ~ -replaced with 50 grams of the divinyl ether of 1,4-cyclohexane dimethanol. The cationic initiator failed to dissolve in the absence of the propenyl ether and an in compatible mixture was formed.
The above cured coatings were compared with that of llA and were evaluated immediately after W exposure.
The results are as reported in the following table.

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--~` 2~114 TABLE

Formula 4 A 5 A 5 B
Adhesion 100% 100%incompatible Double MEK Rubs >loO >100 none Pencil Hardness ~ 2H none This example illustrates that coating hardness can be significantly improved by adding the divinyl ether of 1,4-cyclohexane dimethanol; and that, the dipropenyl ether of triethylene glycol is needed to insure compatibility.

EXAMiPLE 13 Into an amber bottle, 50 grams of >95% cis, cis-dipropenyl ether of triethylene glycol, 50 grams of a divinyl ether of urethane oligomer (prepared as described in the Degree Thesis of Lennart Carlson, Dept. of Polymer Technology, the Royal Institute of Technology, Stockholm, Sweden, 1987), 4 phr* cationic photoinitiator, and 1 phr fluorochemical surfactant were charged and mixed at 50C.
until homogeneous. The resulting liquid was coated on an ~ ;
aluminum panel to a 0.25 mil thickness using a #3 coating ;
bar and then cured as described in Example 11. A tack free coating with the following properties was produced Pencil Hardness 3B
Mandrel Bend 3/16 inch Double MEK rubs 5 * parts/100 parts resin . . .

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Claims

1. An alkenyl ether compound having the formula (I) [X]4-nSi[OR1OCH=CH-R2]n wherein X is halogen, -OR where R is lower alkyl, a mixture of halogen and -OR, a mixture of -OR and hydrogen or a mixture of hydrogen and halogen; R1 contains from 1 to 8 carbon atoms and is alkylene, alkenylene, alkynylene optionally alkoxylated with up to 20 units of where Y is hydrogen or methyl; R2 is hydrogen or lower alkyl and n has a value of from 1 to 4, or having the formula (II) A[(CH2O)m(Z)rCH=CHR]n wherein A is a carbon atom, -OCH=CHR or [C1 to C10 alkyl]4-n; R is C1 to C6 alkyl; Z is C2 to C8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is -OCH=CHR, n has a value of 2 or 3 when A is [C1 to C10 alkyl]4-n and n has a value of 4 when A is carbon.

2. The compound of claim 1 wherein X is -OR, R2 is hydrogen and n has a value of at least 2, or wherein X
is a mixture containing -OR and wherein the value n in said mixture is primarily 3, or which is a mixture of poly(vinyloxy lower alkyl) orthosilicates, or wherein said mixture contains Si[OR1OCH=CH-R2]4

3. The mixture of claim 2 which contain (vinyl oxybutyl) ethyl orthosilicates, or tris(vinyl oxybutyl) ethyl orthosilicate.

4. The process which comprises forming a mixture containing a vinyl ether, epoxide or acrylate resin, a cure enhancing amount of the alk-1-enyl ether silicate of claim 1 and an effective cure promoting amount of a cationic photoinitiator; coating the resulting mixture on a substrate and curing said mixture by exposure to a source of radiation for a period sufficient to provide a tack free coating on said substrate, wherein between about 5 and about 75 wt. % of said alk-1-enyl ether silicate is added to said resin, wherein said alk-1-enyl ether silicate is a mixture of about 80% tris(vinyl oxybutyl) ethyl orthosilicate and about 15% bis(vinyl oxybutyl) ethyl orthosilicate.

5. A radiation curable composition comprising (a) between about 0.1 and about 5 wt. % of a photoinitiator containing at least 25% cationic photoinitiator; (b) between about 30 and about 99 wt. % of a polymerizable vinyl ether, epoxy ether, epoxyacrylate and/or vinyloxy alkyl urethane and (c) between about 1 and about 60 wt. %
of the alk-1-enyl ether silicate of claim 1.

6. A radiation curable, cross linkable composition comprising (a) from about 0.1 to about 5 wt. %
of an initiator containing at least 25% cationic initiator, (b) from about 0 to about 60 wt. % of a polymerizable vinyl ether, epoxy ether, epoxy acrylate and/or vinyloxy alkyl urethane and (c) from about 35 to about 99.9% wt. % of an aliphatic polyfunctional alkenyl ether having the formula (II) A[(CH20)m(Z)rCH=CHR]n wherein A is a carbon atom, -OCH=CHR or [C1 to C10 alkyl]4-n; R is C1 to C6 alkyl; Z is C2 to C8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is -OCH=CHR, n has a value of 2 or 3 when A is [C1 to C10 alkyl]4-n and n has a value of 4 when A is carbon.

7. The composition of claim 6 wherein the aliphatic alkenyl ether is [lower alkyl]4-n[CH2O(Z)rCH=CH(lower alkyl)]n where n has a value of 3, or a compound which is the tetraprop-1-enyl ether of pentaerythritol, or (lower alkyl)CH2O(Z)rCH=CH(lower alkyl), or the aliphatic alkenyl ether is the dipropenyl ether of triethylene glycol, or wherein the aliphatic alkenyl ether is asymmetrical and is a mixture containing at least about 35%
cis isomer with respect to the trans isomer.