AU641152B2 - Free-radical curable compositions - Google Patents

Description

FREE-RADICAL CURABLE COMPOSITIONS

Cross-Reference to Related Applications

This application is a Continuation-in-Part of U.S. Application Serial No. 404,578, filed September 8, 1989 which is a Continuation-in-Part of U.S. Application Serial No. 319,566 filed March 7, 1989

Technical Field

This invention is directed to free-radical curable compositions that are useful as coatings for various substrates.

Background of the Invention

There are many applications that require a rapidly curable coating composition that adheres to a substrate, is flexible, does not discolor and has low toxicity. For example, optical glass fibers are

frequently coated with two superposed coatings. The coating that contacts the glass is a relatively soft, primary coating that must satisfactorily adhere to the fiber and be soft enough to resist microbending

especially at low service temperatures. The outer, exposed coating is a much harder secondary coating that provides the desired resistance to handling forces yet must be flexible enough to enable the coated fiber to withstand repeated bending without cracking the coating.

Other applications, e.g., optical fabrication, coatings for substrates including glass, metal, wood, plastic, rubber, paper, concrete, and fabrics, and adhesives also require compositions that are fast curing, have low toxicity and provide good physical properties.

Compositions that include low molecular weight (meth) acrylate diluents have been utilized for many of these applications. However, these (meth) acrylate diluents are hazardous to human health. Therefore, it is desirable to eliminate or reduce the amount of low molecular weight (meth) acrylate diluents present in a composition.

Vinyl ether compositions have been utilized as replacements for (meth)acrylates. Although vinyl ethers rapidly cure when exposed to ultraviolet light in the presence of a cationic curing catalyst, their cure under cationic conditions leaves catalyst residues that discolor the cured compositions and cause them to be sensitive to water. Furthermore, vinyl ether containing oligomers having relatively high equivalent weights, e.g., an equivalent weight in excess of about 500, do not cationically cure upon exposure to dosages of energy less than 3 Joules per square centimeter. Vinyl ethers do not homopolymerize in the presence of free-radical initiators. Therefore, vinyl ethers are not suitable replacements for (meth)acrylates.

Unsaturated polyesters, e.g., maleates and fumarates, are known to be substantially non-toxic, but are unsatisfactory as replacements for (meth) acrylates because their rate of cure when exposed to ultraviolet light is not satisfactory for certain applications.

European Patent Application No. 0 322 808 published on 05.07.89 discloses a radiation curable composition that comprises an ethylenically unsaturated polyester component and a vinyl ether component having an average of at least two vinyl ether groups per molecule of the vinyl ether component. The unsaturated polyester component can be a polymer, oligomer or mixture thereof. Coatings produced from this

composition are brittle and hard because of the large amount of electron deficient ethylenically unsaturated groups in the backbone of the polyester component which leads to short chain segments between cross-links. The vinyl ether component reacts with the unsaturated group and results in a high degree of cross-linking that causes the cured composition to be brittle, inflexible and hard. Thus, coatings produced from the composition of this European Patent Application do not possess the needed flexibility and softness for applications, such as optical glass fiber coatings, that require a flexible and soft coating.

Summary of the Invention

The invention is directed to free-radical curable compositions that comprise a (meth) acrylate oligomer; and at least one of a single functionality diluent, a mixture of single functionality diluents, and a dual functional monomer, wherein the ratio of

electron-rich double bonds to electron deficient double bonds in the compositions is in the range of about 5:1 to about 1:5.

Optionally, the compositions of the present invention can further comprise at least one of a

reactant having a saturated backbone and an average of at least one electron deficient ethylenically

unsaturated end group per molecule of reactant and an oligomer having an average of at least one electron-rich ethylenically unsaturated group per molecule of

oligomer. The electron deficient group of the reactant is preferably an ethylenically unsaturated dicarboxylate group. The electron-rich group of this oligomer is preferably a vinyl ether group.

The (meth) acrylate oligomer has a number average molecular weight of at least about 1000 daltons and preferably constitutes a minor amount of the

composition.

The single functionality diluent has only one type of reactive group, e.g., an electron-rich

ethylenically unsaturated group such as a preferred vinyl ether group or an electron deficient ethylenically unsaturated group such as a preferred dicarboxylate group on the same molecule of diluent.

The dual functional monomer has at least one electron-rich ethylenically unsaturated group such as a vinyl ether group and at least one electron deficient ethylenically unsaturated group such as an unsaturated dicarboxylate group.

The saturated reactant is the reaction product of a polyester backbone containing component and/or a non-polyester backbone containing component and an electron deficient ethylenically unsaturated end group containing component.

The vinyl ether containing oligomer is the reaction product of a saturated backbone containing component and a vinyl ether having a hydroxyl group or an amine group.

The compositions of the present invention are curable upon exposure to ionizing radiation, actinic energy and heat. The cured compositions exhibit good flexibility, tensile strength, percent elongation, toughness, abrasion resistance, tear resistance and adhesion to substrates. The (meth) acrylate oligomers are relatively inexpensive and their use can lower the cost of the compositions.

Suitable uses for these compositions include optical glass fiber coatings, paper coatings, coatings for the metallization of non-metallic substrates, e.g., plastics, coatings for rubber, metal, wood, concrete, leather, fabric and glass, optical fabrication,

lamination of glass and other materials, i.e.,

composites, dentistry, proSthetics, adhesives, inks, flexigraphic printing plates, and the like.

Even when the oligomer containing the vinyl ether moiety has an equivalent weight in excess of about 500, compositions of the present invention that contain the vinyl ether containing oligomers are curable by a free-radical mechanism. Cationic curing of these

oligomers is not practical.

Thus, the present invention provides compositions having many properties desired by industry while overcoming the shortcomings of the prior art.

Detailed Description of Preferred Embodiments

The present invention is directed to free-radical curable compositions that comprise a

(meth) acrylate oligomer and at least one of a single functionality diluent, a mixture of single functionality diluents and a dual functional monomer, wherein the ratio of electron-rich double bond to electron deficient double bonds in the compositions is in the range of about 5:1 to about 1:5.

The free-radical curable compositions of the present invention can further comprise at least one of a saturated reactant having a saturated backbone and an average of at least one electron deficient ethylenically unsaturated end group per molecule of saturated reactant and an oligomer having an average of at least one electron-rich ethylenically unsaturated group per molecule of oligomer. The electron deficient

ethylenically unsaturated end group of the saturated reactant is preferably a dicarboxylate group. The electron-rich ethylenically unsaturated group of the oligomer having at least one electron-rich group is preferably a vinyl ether group.

The term "(meth) acrylate", and various

grammatical forms thereof, identifies esters that are the reaction product of acrylic or methacrylic acid with a hydroxy group-containing compound.

The term "single functionality diluent", as used in its various grammatical forms, defines a diluent having only one type of reactive group, e.g., an electron-rich ethylenically unsaturated group such as a vinyl ether group or an electron deficient ethylenically unsaturated group such as a maleate on the same molecule of diluent. However, this diluent can be

polyfunctional, i.e., a molecule can have more than one reactive group provided all reactive groups are of the same type. An admixture of single functionality

diluents can have electron-rich groups and electron deficient groups.

The single functionality diluent, including admixtures thereof, is preferably selected, i.e., both the type of reactive group (s) of the single

functionality diluent(s) and the amount utilized are chosen, to provide in the composition a ratio of

electron-rich double bonds to electron deficient double bonds of about 5:1 to about 1:5, preferably about 2:1 to about 1:2. Most preferably this ratio is about 1:1.

The term "dual functional monomer", as used herein, defines a monomer having at least one

electron-rich ethylenically unsaturated group that preferably is a vinyl ether group and at least one electron deficient ethylenically unsaturated group that preferably is a dicarboxylate group. The ratio of electron-rich groups to electron deficient groups in the monomer can be selected to achieve the desired ratio of electron-rich double bonds to electron deficient double bonds in the composition.

The term "vinyl ether", in its various grammatical forms, refers to a vinyl group bound to an oxygen atom which is bound to a carbon atom.

The (meth) acrylate oligomers suitable for use in the present invention preferably contain an average of at least about 1.2, more preferably about 2 to about 4, (meth) acrylate groups per oligomer. These (meth) acrylate oligomers are illustrated by Cargill 1570, a diacrylate ester of Bisphenol A epichlorohydrin epoxide resin having a number average molecular weight of about 700 daltons that is

commercially available from Cargill, Carpentersville, IL.

The term "dalton", as used herein in its various grammatical forms, defines a unit of mass that is 1/12th the mass of carbon-12.

The (meth) acrylate oligomer can be a poly (meth) acrylate of an epoxy functional resin. These poly (meth) acrylates preferably contain an average of more than about two (meth) acrylate groups per oligomer and are exemplified by the commercial product Novacure 3700 available from Interez, Inc., Louisville, KY, which is the diester of Epon 828 and acrylic acid. Epon 828 is an epoxy functional resin that is a diglycidyl ether of Bisphenol A that is commercially available from Shell Chemicals, New York, NY. The number average molecular weight of Novacure 3700 is about 500 daltons and of Epon 828 is about 390 daltons.

Diacrylate-modified polyurethanes are also useful as the (meth) acrylate oligomers, especially those that employ a polyester base. Particularly preferred are acrylate-capped polyurethanes that are the urethane reaction products of a hydroxy-functional polyester, especially one having an average of about 2 to about 5 hydroxy groups per molecule, with a monoacrylate

monoisocyanate. These acrylate-capped polyurethanes are illustrated by a polyester made by reacting trimethylol propane with a caprolactone to a number average

molecular weight of about 600 daltons followed by reaction with three molar proportions of the reaction product of 1 mol of 2-hydroxyethyl acrylate with 1 mol of isophorone diisocyanate. The end product is a polyurethane triacrylate. The urethane-forming reaction is conventionally performed at about 60°C in the

presence of about 1 percent by weight of dibutyltin dilaurate. A commercial, polyester-based polyacrylatemodified polyurethane that is useful herein is Uvithane 893 available from Thiokol Chemical Corp., Trenton, NJ. The polyester in the Uvithane 893 product is a polyester of adipic acid with about 1.2 molar proportions of ethylene glycol polyesterified to an acid number of less than about 5. This polyester is converted as described above to a polyacrylate-modified polyurethane that is a semi-solid at room temperature and that has an average unsaturation equivalent of about 0.15 to about 0.175 ethylenically unsaturated groups per 100 grams of resin.

In polyester processing, the acid number, defined as the number of milligrams of base required to neutralize one gram of polyester, is used to monitor the progress of the reaction. The lower the acid number, the further the reaction has progressed.

A polyacrylate-modified polyurethane that is suitable as the (meth) acrylate oligomer is the reaction product of 1 mol of diisocyanate, 1 mol of

2-hydroxyethyl acrylate (HEA) and about 1 weight percent dibutyltin dilaurate reacted at a temperature of about 40°C for a time period of 4 hours that is subsequently reacted at a temperature of about 60°C for a time period of about 2 hours with 1 mol of a commercial hydroxy end-functional caprolactone polyester. A suitable caprolactone polyester is the reaction product of 2 mols caprolactone and 1 mol of ethylene glycol reacted at a temperature of about 60°C for a time period of 4 hours. A suitable commercial caprolactone polyester is

available from Union Carbide Corp., Danbury, CT, under the trade designation Tone M-100 which has a number average molecular weight of about 345 daltons. The number average molecular weight of the (meth) acrylate oligomers is preferably about 1,000 to about 15,000, more preferably about 1,200 to about

6,000, daltons.

The equivalent weight of the (meth) acrylate oligomers is preferably about 500 to about 5,000, more preferably about 600 to about 3,000.

The single functionality diluents suitable for use herein include vinyl ether diluents, vinyl amides, divinyl ethers, ethylenically unsaturated

monocarboxylates and dicarboxylates that are not

acrylates, the like and mixtures thereof.

Further representative of the single functionality diluents are N-vinyl pyrrolidinone,

N-vinyl imidazole, 2-vinylpyridine, N-vinyl carbazole, N-vinyl caprolactam, the like, and mixtures thereof.

Representative of other single functionality diluents are the divinyl ethers of triethylene glycol or of any other diol, such as 1,6-hexane diol or dibutylene glycol. One may also use polyvinylates of other

polyhydric alcohols, such as glycerin or trimethylol propane. Polyhydric polyethers can be used, such as ethylene oxide, propylene oxide or butylene oxide adducts of polyhydric alcohols, illustrated by ethylene glycol, butylene glycol, glycerin, trimethylol propane or pentaerythritol.

Preferred single functionality diluents are triethylene glycol divinyl ether commercially available from GAF under the trade designation Rapicure DVE-3, diethyl maleate, butane diol divinyl ether, 1,4-cyclohexane dimethanol divinyl ether, octyl vinyl ether, diethyl furmarate dimethyl maleate, the like, and mixtures thereof. The single functionality diluents can have an average of about 1 to about 4 , preferably about 1 to about 3, reactive groups per molecule.

The dual functional monomer can be represented by the following Formula I:

(I)

wherein R^a is selected from the group consisting of H, C₁ to C₁₀ alkyl or allyl groups, C₅ to C₁₀ aryl groups, metal ions, heteroatoms and combinations of carbon and heteroatoms; R^b is absent or selected from the group consisting of O, C(R^a)₂, heteroatoms or substituted heteroatoms; R^c is an aliphatic, branched or cyclic alkyl group or an arylalkyl group that contains 1 to about 10 carbon atoms, and can contain heteroatoms; and Y is selected from the group consisting of:

wherein each R^d is independently selected from the group consisting of H, C₁ to C₄ alkyl groups, C₅ to C₁₀ aryl groups and electron withdrawing groups.

Preferably, R^a is a C₁ to C₄ alkyl group, R^b is O, R^c is a C₂ to C₈ alkyl group and each R^d is H.

The heteroatoms that can be present in the dual functional monomer include non-carbon atoms such as oxygen, nitrogen, sulfur, silicon, phosphorus and the like.

Representative of electron withdrawing groups are CN, SO₂, SO₃, CONH₂, Cl, CO₂ and the like. The saturated reactant is the reaction product of a polyester backbone containing component and/or a non-polyester backbone containing component and an electron deficient ethylenically unsaturated end group containing component.

The saturated polyester backbone containing component can be represented by hydroxy functional saturated dicarboxylates, polycarbonates,

polycaprolactones and the like.

Representative of the dicarboxylates are the reaction products of saturated polycarboxylic acids, or their anhydrides, and diols. Suitable saturated

polycarboxylic acids and anhydrides include phthalic acid, isophthalic acid, terephthalic acid, trimetillitic acid, tetrahydrophthalic acid, hexahydrophthalic acid, tetrachlorophthalic acid, adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, malonic acid, pimelic acid, suberic acid, 2,2-dimethylsuccinic acid, 3,3-dimethylglutaric acid, 2,2-dimethylglutaric acid, the like, anhydrides thereof, and mixtures

thereof. Suitable diols include 1,4-butane diol,

1,8-octane diol and the like.

Representative of the saturated polycarbonates are polyhexamethylene carbonate commercially available from PPG Industries under the trade designation Duracarb 120 and polycyclohexane dimethylene carbonate

commercially available from PPG Industries under the trade designation Duracarb 140.

Representative of the polycaprolactones are the Tone Polyol series of products, e.g., Tone 0200,

0221, 0301, 0310, 2201 and 2221, commercially available from Union Carbide, New York, NY. Tone Polyol 0200, 0221, 2201 and 2221 are difunctional. Tone Polyol 0301 and 0310 are trifunctional. The saturated, non-polyester backbone

containing component can be represented by hydroxy functional polyethers, Bisphenol-A alkoxylates, and siloxanes and organic polyisocyanates, the like and mixtures thereof. The group linking the ethylenically unsaturated group to the saturated non-polyester

backbone (linking group) can be a urethane, urea, ether, or thio group and the like. The linking group can be an ester when the ethylenically unsaturated end group containing component is a preferred dicarboxylate, dicarboxylic acid or dicarboxylic anhydride.

Representative of the saturated polyethers are polyalkylene oxides, alkyl substituted

poly(tetrahydrofurans), and copolymers of the alkyl substituted tetrahydrofurans and a cyclic ether.

Representative of the polyalkylene oxides are poly (propylene oxide), commercially available from Union Carbide under the trade designation Niax PPG 1025 and poly(tetramethylene glycol), commercially available from DuPont under the trade designation Terathane 1000.

The alkyl substituted poly(tetrahydrofurans) have ring structures that open during polymerization. The alkyl group of the alkyl substituted

poly(tetrahydrofurans) has about 1 to about 4 carbon atoms. Representative of the alkyl substituted

poly(tetrahydrofurans) are poly(2-methyltetrahydrofuran) and poly(3-methyltetrahydrofuran). Representative of the cyclic ethers with which the alkyl substituted tetrahydrofurans can be copolymerized are ethylene oxide, propylene oxide, tetrahydrofuran and the like.

Representative of the Bisphenol-A alkoxylates are those wherein the alkoxy group contains about 2 to about 4 carbon atoms, e.g., ethoxy. A commercial

Bisphenol-A alkoxylate is the Bisphenol-A diethyoxlate available under the trade designation Dianol 22 from Akzo Research, The Netherlands.

Representative of the siloxanes is

poly(dimethylsiloxane) commercially available from Dow Corning under the trade designation DC 193.

Any of a wide variety of organic

polyisocyanates, alone or in admixture, can be utilized, diisocyanates alone or in admixture with one another preferably constituting all or almost all of this component. Representative diisocyanates include

isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), diphenylmethylene diisocyanate, hexamethylene diisocyanate, cyclohexylene diisocyanate, methylene dicyclohexane diisocyanate, 2,2,4-trimethyl

hexamethylene diisocyanate, m-phenylene diisocyanate, 4-chloro-1,3-phenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate,

1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,10-decamethylene diisocyanate,

1,4-cyclohexylene diisocyanate, and polyalkyloxide and polyester glycol diisocyanates such as

polytetramethylene ether glycol terminated with TDI and polyethylenic adipate terminated with TDI, respectively.

The polyester backbone containing component and/or the non-polyester backbone containing component are reacted with an ethylenically unsaturated group containing component that can be the reaction product of an ethylenically unsaturated dicarboxylic acid and a monohydric alcohol or an aforementioned cyclic ether.

Representative unsaturated dicarboxylic acids are maleic acid, maleic anhydride, fumaric acid, and itaconic acid.

Representative of the monohydric alcohols are the C₁ to C₁₀ alcohols, e.g., ethanol, decanol, the like and mixtures thereof. If the ester produced by the reaction of the dicarboxylic acid, or anhydride, and the alcohol, or cyclic ether, has unreacted carboxyl groups, the ester can be conventionally reacted with a material having a group that is reactive with the carboxyl groups of the ester, e.g., hydroxy groups and epoxy groups.

Preferably, this material is resinous and has a number average molecular weight of about 300 to about 5000, more preferably about 500 to about 3,500 daltons.

The saturated reactant preferably has an average of about 1 to about 10, more preferably about 2 to about 5, electron deficient ethylenically unsaturated end groups per molecule of reactant.

The equivalent weight of the saturated

reactant having electron deficient ethylenically

unsaturated end groups is preferably about 100 to about 10,000, more preferably about 200 to about 1,000.

Oligomers having an average of at least one electron-rich ethylenically unsaturated end group per molecule of oligomer, preferably a vinyl ether

containing oligomer, can be utilized in addition to, or in place of, the saturated reactant in the compositions of the present invention.

The vinyl ether containing oligomer can be produced by conventionally reacting a monohydric or monoamine vinyl ether and a saturated backbone moiety containing component. The backbone containing component is represented by hydroxy functional polyesters, polycarbonates, siloxanes, polycaprolactones,

Bisphenol-A alkoxylates, polyethers, and organic polyisocyanates, the like and mixtures thereof. The backbone of the vinyl ether containing oligomer can contain repeating backbone units. The group linking the vinyl ether group to the saturated backbone (linking group) can be a urethane, urea, ester, ether, or thio group and the like. Preferred linking groups are

urethane, urea and ester groups. Mixtures of linking groups can be used.

Representative of the vinyl ethers suitable as reactants in the production of the vinyl ether

containing oligomer are conventional vinyl ethers including triethylene glycol monovinyl ether and

1,4-cyclohexane dimethylol monovinyl ether.

Representative of the saturated polyesters, polyethers, polycaprolactones, Bisphenol-A alkoxylates, and siloxanes are those utilized in producing the saturated reactant.

The oligomers containing vinyl ether groups can be the reaction product of an organic

polyisocyanate, preferably a diisocyanate (especially a diphenylalkane diisocyanate in which the alkane group contains 1 to 8 carbon atoms), and a transvinylated polyhydric alcohol mixture containing hydroxy groups that is the transvinylation reaction product of (1) at least one vinyl ether and (2) at least one polyhydric alcohol having an average of more than 2 hydroxy groups per molecule. The polyisocyanate is present in an amount effective to consume substantially all of the available hydroxy groups in the transvinylation mixture.

The term "transvinylation", as used in its various grammatical forms, means that the vinyl ether group of the vinyl ether and the hydroxy group of the alcohol are exchanged.

The terms "transvinylation mixture" and

"transvinylation polyhydric alcohol mixture", as used in their various grammatical forms, mean unreacted

polyhydric alcohol, partially transvinylated polyhydric alcohol and fully transvinylated polyhydric alcohol are present in the transvinylation reaction product of the vinyl ether and the polyhydric alcohol. The transvinylation mixture is preferably, but not

necessarily, an equilibrium mixture.

The term "substantially all", in its various grammatical forms, when used in reference to the

isocyanate consuming the hydroxy groups (hydroxy

functionality), means that if the vinyl ether containing oligomer has hydroxy groups, they are not present in an amount that adversely affects the properties of the compositions.

The transvinylated aliphatic polyhydric alcohol mixture can contain partially vinylated

polyhydric alcohols and at least about 3 percent to about 90 percent by weight of unreacted polyhydric alcohols. The polyisocyanate consumes substantially all of the available hydroxy functionality. Simple

monohydric alcohols (which are formed when a C₁ to C₄ alkyl vinyl ether is used) are preferably removed to provide a transvinylation mixture that is substantially free of simple monohydric alcohol. Such an alcohol functions to terminate the vinyl ether containing oligomer which is formed, an action that is undesirable, but tolerable in some instances.

The term "simple monohydric alcohol", as used in its various grammatical forms, refers to a short chain alcohol containing 1 to 4 carbon atoms and having only one hydroxy group per molecule.

The transvinylated mixture is produced by transvinylating a vinyl ether with at least one

polyhydric alcohol which preferably contains an average of more than 2 hydroxy groups per molecule, whereafter any simple monohydric alcohol by-product of the

transvinylation reaction and the transvinylation

catalyst are normally removed. More particularly, the vinyl ether containing oligomers are prepared from the transvinylation reaction product of an arylalkyl polyhydric alcohol, which most preferably contains or consists of polyhydric alcohols having an average of 3 or more hydroxy groups per molecule, and a vinyl ether which can contain one or more vinyl ether groups per molecule. The transvinylated reaction product contains partially transvinylated polyhydric alcohols as well as unreacted polyhydric alcohols, and it can also contain fully transvinylated polyhydric alcohols.

The transvinylation reaction is conveniently carried out in the presence of a catalyst that is known for use in this reaction. While it is not essential, the catalyst and the simple monohydric alcohol

by-products of the reaction can both be optionally removed, and this usually also removes any unreacted monovinyl ether which may be present.

It is desired to point out that the catalyst is conventionally removed by filtration, which is a particularly simple operation. Any simple monohydric alcohols and any unreacted monovinyl ether which can be present when a monovinyl ether is used in the

transvinylation reaction are highly volatile and easily removed by evaporation from the reaction product, leaving the balance of the transvinylation reaction product intact. This method of operation eliminates the need to distill off the monohydric vinyl ether utilized in conventional compositions, and other components that are distilled off with this monohydric vinyl ether, from the potassium hydroxide catalyst used in the reaction with acetylene. The distillation step utilized in the prior art is a difficult operation involving elevated temperature which causes undesired side reactions.

Filtration by a chromatography procedure is a representative method of removing the catalyst. In this procedure a 5 inch by 1.5 inch silica gel column (70 to 230 U.S. Sieve Series mesh and having a pH neutral surface) has a 0.5 inch layer of activated carbon placed thereon. The carbon is commercially available from

Darco under the trade designation G-60 and passes through a 100 U.S. Sieve Series mesh. The column is wetted with triethylene glycol divinyl ether then the catalyst containing transvinylation mixture is poured through the column. The first 100 milliliters (ml) of eluent are discarded and the remaining eluent is

collected as the transvinylation mixture.

The catalyst utilized herein is a conventional transvinylation catalyst and is illustrated by the elements of Groups IB, IIB, IVB, VB, VIB, VIIB, and VIII of the Periodic Table of Elements. Representative catalysts include palladium, mercury, copper, zinc, magnesium, cobalt, mercuric acetate, mercury (II) salts, lithium chloropalladite (I) dialkylpyridines, phosphates of thallium, vanadium, chromium, manganese, iron;

cobalt, nickel, Group VI oxyacid salts and mixtures thereof. A presently preferred catalyst is palladium (II).

The catalyst used herein can be a finely divided powder and can be removed by filtration. The addition of charcoal to the transvinylation mixture can assist the filtration process, e.g., when a finely divided powder form of the catalyst is utilized. The simple monohydric alcohol and any volatile alkyl

monovinyl ether which is present when an alkyl monovinyl ether is used for transvinylation is preferably removed by vaporization, and this is conveniently performed when methyl or ethyl vinyl ethers are used by applying a reduced pressure to the reaction product at room

temperature, i.e., a temperature of about 20° to about 30°C. It is desired to restrict the purification operation to simple filtration, and this is done herein by using a polyvinyl ether, such as a divinyl ether of a diol illustrated by triethylene glycol divinyl ether, as a transvinylation reactant.

The catalyst can be bound to a solid matrix such as charcoal, nickel, alumina, ion exchange resins, molecular sieves, zeolites, or similar materials. The solid matrix having catalyst bound thereto can be in the shape of beads, filings, part of the walls of a column, and the like. Alternatively, the solid matrix having catalyst bound thereto can be packed in a column.

The product of the transvinylation reaction is a mixture containing partially transvinylated polyhydric alcohols. Accordingly, there is present on these partially transvinylated polyhydric molecules at least one vinyl ether group and at least one hydroxy group, so the transvinylation mixture tends to deteriorate with time and exposure to elevated temperature, at least partially by the formation of acetal groups. Reaction with a polyisocyanate in accordance with this invention significantly reduces the hydroxy content to minimize or largely avoid this deterioration. Prior to reaction with polyisocyanate, the present transvinylation mixture does not require an elevated temperature distillation operation. The elimination of this distillation

operation further minimizes this deterioration of the transvinylation mixture.

The transvinylation mixture will normally contain some unreacted polyhydric alcohols and some fully vinylated polyvinyl alcohols, as previously indicated, and these are not removed. This introduces an important economy at the same time that it enables one to increase the molecular weight and the vinyl ether functionality by reaction of the transvinylation mixture with organic polyisocyanates. Increased molecular weight, the presence of internal urethane or urea groups, and the increased vinyl ether functionality all introduce physical toughness into the cured products.

In preferred practice, the partially transvinylated polyhydric alcohols in this invention contain from 3 percent to 25 percent unreacted

polyhydric alcohols, about 30 to about 94 percent partially transvinylated polyhydric alcohols, and from 3 percent to 25 percent fully transvinylated polyhydric alcohols. This is particularly preferred when the polyhydric alcohol that is transvinylated contains 3 or 4 hydroxy groups.

The transvinylation reaction to produce vinyl ethers is itself known, and illustrative articles describing this reaction using alkyl vinyl ethers are, McKeon et al, "The Palladium (II) Catalyzed Vinyl

Interchange Reaction - I", Tetrahedron 28:227-232 (1972) and McKeon et al., "The Palladium (II) Catalyzed Vinyl Interchange Reaction - II", Tetrahedron 28:233-238

(1972). However, these articles teach purifying the reaction product and do not suggest the use of a

transvinylation mixture.

A method of synthesizing pure vinyl ethers is disclosed in Smith et al., "A Facile Synthesis of Low and High Molecular Weight Divinyl Ethers of

Poly (oxyethyrene)", Polymer Preprints 28 (2) : 264-265 (August, 1987). Smith teaches the synthesis of pure vinyl ethers using transetherification chemistry based on the palladium (II) catalysts of poly(oxyethylene) glycols and ethyl vinyl ether.

While the transvinylation mixture can use a diol as the polyhydric alcohol, it preferably employs triols and tetrols (most preferably triols). Indeed, when diols are used some higher functional polyol is preferably added to the mixture that is transvinylated or to the transvinylation mixture that is reacted with the diisocyanate. Suitable higher functional polyols include the triols and higher hydroxy functional polyols referred to herein. Thus, the polyhydric alcohol can be a mixture of alcohols and has an average hydroxy

functionality per molecule of more than 2.

Moreover, the transvinylation reaction forms unrefined transvinylation mixtures which are further reacted to enhance stability of the transvinylation mixture by the formation of vinyl ether containing oligomers in which the molecular weight and vinyl ether functionality are both increased.

Suitable polyhydric alcohols for use in this transvinylation reaction can be arylalkyl or aliphatic polyhydric alcohols having an average of more than 2, preferably at least 3, hydroxy groups per molecule on the aliphatic or alkyl portion thereof. It is presently preferred that the polyhydric alcohols can have up to about an average of about 10 hydroxy groups per

molecule.

The polyhydric alcohol utilized is preferably soluble in the vinyl ether and has a number average molecular weight of up to about 2,000 daltons. We preferably employ polyhydric alcohols that are liquid at room temperature, i.e., a temperature of about 20° to about 30° C., or which (if solid) have a number average molecular weight below about 400 daltons.

The alkyl group of these arylalkyl polyhydric alcohols preferably contains about 2 to about 10, more preferably about 3 to about 6, carbon atoms. The aryl group of these polyhydric alcohols preferably contains up to about 20, more preferably up to about 10, carbon atoms. Illustrative arylalkyl polyhydric alcohols include ethoxylated polyhydric phenols, hydroxy

substituted ring structures, e.g., phenol, naphthol, and the like, that are alkoxylated, trimethylol benzene, and the like, and mixtures thereof. Preferred polyhydric alcohols are aliphatic polyhydric alcohols that contain 2 to 10 carbon atoms, more preferably 3 to about 6 carbon atoms, and are illustrated by ethylene glycol, butylene glycol, ester diol, 1,6-hexane diol, glycerol, trimethylol propane, pentaerythritol, and sorbitol. Trimethylol propane is particularly preferred.

The polyhydric alcohol can be a polyether, such as the ethylene oxide or propylene oxide adducts of the polyhydric alcohols noted previously. These are illustrated by the propylene oxide adduct of trimethylol propane that has a number average molecular weight of about 1500 daltons.

The polyhydric alcohol can also be a saturated polyester of the polyhydric alcohols noted previously, such as the reaction product of trimethylol propane with epsilon caprolactone having a number average molecular weight of about 600 and the reaction product of two mols of ethylene glycol with one mol of adipic acid.

Still other polyhydric alcohols are illustrated by resinous materials that contain hydroxy groups, such as styrene-allyl alcohol copolymers, acrylic copolymers containing 2 percent to 20 percent of copolymerized 2-hydroxyethyl acrylate, and even starch or cellulose. However, these have a higher hydroxy functionality than is now preferred.

The polyhydric alcohol can also be amine substituted, e.g., triethanolamine.

It is desired to stress that the reaction with acetylene utilized in the prior art is not applicable to many of the polyhydric alcohols which are particularly attractive for use in producing the present

transvinylation mixture. Polyesters and polycarbonates, such as 1,6-hexane diol polycarbonate having a molecular weight of about 1,000 daltons, are degraded by the potassium hydroxide catalyst used in reaction with acetylene, but can be transvinylated in accordance with the present transvinylation process.

Suitable vinyl ethers can be represented by the following general Formula II:

wherein R^e,-R^f, R⁹, R^h, and Rⁱ are each independently selected from the group of hydrogen and lower alkyl groups containing 1 to 4 carbon atoms; R^e, or R^f, and R⁹ joined together can be part of a ring structure; R^e, or R^f, and R^h, or Rⁱ, joined together can be part of a ring structure; and R⁹ and R^h, or R^c, joined together can be part of a ring structure; R^j is an aromatic or aliphatic group that is reactive only at the site(s) where a vinyl ether containing radical is bound; x is 0 or 1; and n is equal to 1 to 10, preferably 1 to 4, with the proviso that n is less than or equal to the number of reactive sites of R^j.

R^j can contain heteroatoms, i.e., atoms other than carbon atoms, such as oxygen, nitrogen, sulfur, silicon, phosphorus, and mixtures of heteroatoms alone or in combination with carbon atoms. R^j can contain 1 to about 20, preferably 1 to about 10, atoms. R^j is preferably a straight or branched carbon containing group containing 1 to about 8, more preferably 1 to about 4, carbon atoms and can preferably contain oxygen atoms.

Representative of vinyl ethers of Formula II are dihydropyran and dimethylol benzene divinyl ether. Preferred vinyl ethers for use in the

transvinylation reaction can be represented by the following general Formula III:

(III) (CH₂ = CH - O - CH₂ )-_n R^k

wherein R^k is an aliphatic group that is reactive only at the site(s) where a vinyl ether containing radical is bound and n is equal to 1 to 4.

R^k contains at least one carbon atom and can contain heteroatoms and mixtures of heteroatoms.

Preferably, R^k contains 1 to about 4 carbon atoms and can contain oxygen atoms.

Vinyl ethers having the structure of Formula

III are illustrated by divinyl ethers, such as

1,4-butane diol divinyl ether, 1,6-hexane diol divinyl ether, and triethylene glycol divinyl ether. Polyvinyl ethers of higher functionality are illustrated by trimethylol propane trivinyl ether and pentaerythritol tetravinyl ether.

Illustrative monovinyl ethers having the structure of Formula III are ethyl vinyl ether, methyl vinyl ether, n-butyl vinyl ether, and the like,

including phenyl vinyl ether. The presently preferred monovinyl ether is ethyl vinyl ether which releases ethanol on reaction.

The equivalent ratio of the vinyl ether to the hydroxy groups in the polyhydric alcohol is in the range of about 0.5:1 to about 5:1, preferably 0.8:1 to 2:1.

Possibly of greater significance, the polyhydric alcohol is transvinylated to react with from 10 percent to 90 percent, preferably from 30 percent to 80 percent, of the hydroxy groups which are present thereon. The higher the functionality of the polyhydric alcohol, the higher the proportion of hydroxy groups thereon which should be reacted by transvinylation.

As previously discussed, a palladium (II) catalyst can be utilized. Illustrative palladium

catalysts are PdCl₂, (PhCN)₂PdCl₂, diacetato- (2,2'-bipyridyl)palladium (II), diacetato- (1,10-phenanthroline)palladium (II), diacetato- (N,N,N',N'-tetramethylenediamine) palladium (II),

diacetato(P,P,P',P'-tetraphenyl-1,2-diphosphino-ethane) palladium (II), and the like.

Diacetato-(1,10-phenanthroline)-palladium (II) is a preferred palladium (II) catalyst.

The catalyst is usually present in a range of about 0.001 to about 1 percent, preferably about 0.1 percent, by weight based on the total weight of the polyhydric alcohol and vinyl ether.

The transvinylation reaction is a conventional one, as previously indicated, and is described in the articles noted previously. We employ a closed vessel which is charged with the appropriate amounts of the polyhydric alcohol, vinyl ether and catalyst and the mixture is stirred and reacted at a temperature of from about room temperature up to about 45°C. The reaction proceeds slowly, and we usually permit it to proceed for an extended period of time up to about 3 days to obtain the desired equilibrium composition. After about 2 days we find that using a 20 percent stoichiometric excess of vinyl ether with respect to hydroxy functionality causes about half of the hydroxy groupe to be consumed in the reaction.

A preferred method of performing the transvinylation reaction is to utilize ultrasonic energy to enhance the transvinylation. In this method an admixture of the vinyl ether, the polyhydric alcohol and the catalyst is exposed to ultrasonic energy for a time period effective to produce the transvinylation mixture. The frequency of the ultrasonic energy is about 10 to about 850 kilohertz (kHz). The ultrasonic

transvinylation reaction is preferably performed at room temperature and pressure, i.e., about one atmosphere.

An illustrative device for supplying ultrasonic energy is a Model B220 ultrasonic cleaner, commercially available from Branson Corp., Shelton, CT. This cleaner has 125 watts of power and provides a frequency of about 30 to about 50 kHz at this power level. In this method the reactants are placed into a suitable vessel which is then placed in the water bath of the cleaner. The cleaner is then activated to enhance the transvinylation reaction.

The transvinylation reaction can be run for a time period sufficient to obtain the desired

transvinylation mixture. A method of determining if the desired transvinylation mixture has been obtained is to test samples by gas chromatography to determine the content of the transvinylation mixture.

After the transvinylation reaction is terminated, it is convenient to remove the catalyst by filtration, and the addition of about 1 percent by weight of charcoal can be helpful. We also prefer to strip off any volatile products which can be present, and this can be done by simply subjecting the reaction product to reduced pressure at room temperature. This removes any residual alkyl monovinyl ether and the simple monohydric alcohol by-product of the reaction, at least when methyl or ethyl vinyl ether is used. With higher monohydric alcohols, modest heat, i.e., heat to achieve a temperature of about 30º to about 60ºC., can be used to help remove volatiles. While the filtration step is preferably carried out prior to removal of volatiles, this sequence can be reversed. When polyvinyl ethers are used, there is no need to subject the transvinylation reaction product to reduced pressure because there is no residual alkyl monovinyl ether or simple monohydric alcohol by-product present, and this is a feature of this invention.

It is preferred that the transvinylation polyhydric alcohol mixture be liquid at room

temperature, but this is not essential since reactive liquid materials can be added, e.g., the aforementioned vinyl ethers such as ethyl vinyl ether or a polyvinyl ether such as ethylene glycol divinyl ether, to permit the further reactions contemplated herein to be carried out. Optionally, any residual alkyl monovinyl ether and simple monohydric alcohol by-product can be retained as a reactive liquid material, but this is usually

undesirable since the monohydric alcohol is

independently reactive with polyisocyanate and functions as a chain-terminating agent and limits the attainment of the desired molecular weight. Other conventional diluents, e.g., N-vinyl pyrrolidone, N-vinyl

caprolactam, and the like can also be present.

The unreacted polyhydric alcohol and partially transvinylated polyhydric alcohol are then converted into a vinyl ether containing oligomer by reaction with the diisocyanate to form a vinyl ether containing oligomer preferably having an average of 1 to about 10, more preferably about 2 to about 5, vinyl ether groups per molecule. The polyisocyanate is utilized in an amount sufficient to substantially eliminate unreacted hydroxy groups present in the transvinylation mixture. Therefore, the isocyanate consumes substantially all of the available hydroxy groups of the transvinylation mixture, i.e., less than about 0.1 percent by weight of hydroxy groups are present in the vinyl ether containing oligomer. Preferably the vinyl ester containing

oligomer has a hydroxy number below about 10.

The reaction with organic polyisocyanates increases the number average molecular weight and the vinyl ether functionality of the resultant vinyl ether containing oligomer. This is especially true to the extent that polyhydric alcohols having a hydroxy

functionality in excess of 2 are used since this

introduces branching or an increase in the number of vinyl ether or divinyl ether groups. While the

polyisocyanate can have a functionality higher than two, it is preferred to utilize diisocyantes because of their availability and also because this minimizes the

tendency to gel when substantially all of the hydroxy functionality is consumed.

A stoichiometric excess of isocyanate groups, based on hydroxy groups, can be used, but a

stoichiometric proportion is preferred. Excess

isocyanate groups, when present, can be later consumed by reaction with any isocyanate reactive group. Thus, one can post-react the excess isocyanate groups of the vinyl ether containing oligomer with an alcohol or amine-functional reagent that can be monofunctional or polyfunctional depending upon whether a further increase in molecular weight or functionality is desired.

The aforementioned polyisocyanates utilized in the production of the saturated reactant are suitable for use in producing the vinyl ether containing

oligomers.

In the reaction between hydroxy and isocyanate groups, it is preferred to employ a stoichiometric balance between hydroxy and isocyanate functionality and to maintain the reactants at an elevated reaction temperature of at least about 40°C. until the isocyanate functionality is substantially consumed. This also indicates the hydroxy functionality is similarly

consumed. One can also use a small excess of isocyanate functionality.

Since diisocyanates are preferably used herein, this means that the polyhydric alcohol used should contain a proportion of polyol having at least three hydroxy groups. Using a triol as illustrative, transvinylation provides a monovinyl ether having two hydroxy groups that is reacted with diisocyanates to provide vinyl ether functionality along the length of the oligomer. Transvinylation also provides a

monohydric divinyl ether which acts as a capping agent. Such a capping agent supplies two vinyl ether groups wherever it appears in the vinyl ether containing oligomer. Both of these triol derivatives increase the vinyl ether functionality of the vinyl ether containing oligomers. Moreover, unreacted triol has the same function, for it provides three branches which must be capped by the vinyl ether-containing capping agent.

Further chain extension, and hence increased molecular weight, can be achieved by the addition of conventional chain extenders including amine functional chain extenders. Illustrative amine functional chain extenders include polyoxyalkylene amines and the

Jeffamine line of products, commercially available from Jefferson Chemicals.

A monohydric capping agent can also be present to prevent gelation. The use, and amount required, of this agent is conventional.

The internal urethane or urea groups are provided by the stoichiometry of the system.

Subtracting the molar proportion of the monohydric capping agent, if such an agent is present, from the number of mols of diisocyanate, the equivalent ratio of hydroxy, and/or amine from the amine functional chain extender if one is utilized, to isocyanate in the unreacted diisocyanate can be about 1:1 and can be up to about 1.2:1. This ratio increases the molecular weight of the vinyl ether containing oligomer and introduces internal urethane or urea groups therein.

Unreacted isocyanate groups can be present in the vinyl ether containing oligomer, but are preferably minimized to less than about 0.1 percent by weight.

More particularly, the residual isocyanate content of the vinyl ether containing oligomer obtained by reaction of the transvinylation mixture with polyisocyanate can be substantial when further reaction, e.g., reaction with an aforementioned amine functional chain extender, is contemplated, but when the vinyl ether containing oligomer is to be used for coating, it is preferred that there be no detectable isocyanate present.

The vinyl ether containing oligomers can comprise the reaction product of an organic diisocyanate with a transvinylation mixture containing hydroxy groups that is the transvinylation reaction product of a divinyl ether having the Formula III, above, and at least one aliphatic polyhydric alcohol having an average of 3 or more hydroxy groups per molecule. The

diisocyanate consumes substantially all of the available hydroxy groups of the transvinylation mixture. The equivalent ratio of vinyl ether to polyhydric alcohol is in the range of about 0.5:1 to about 5:1.

Further examples of suitable vinyl ether containing oligomers are polyvinyl ether polyurethanes and saturated polyesters such as those shown in U.S. Patent Nos. 4,472,019, 4,749,807, 4,751,273, and

4,775,732.

Further representative vinyl ether containing oligomers are obtained by the metathesis of a cyclic olefin ether having the following general Formula IV:

wherein each R^l independently can be hydrogen or an alkyl, aryl, cycloaliphatic or halogen group and m is a number in the range of about 2 to about 10, preferably about 5 to about 6. Metathesis, which is described in March, Advanced Organic Chemistry, Third Edition, copyright 1985 by John Wiley & Sons, Inc., pp 1036-1039 & 1115, results in the opening of the ring of the cyclic olefin ether to produce an oligomer having the following general Formula V:

(V) Z [ (CR^lR^l)_m - O - CR^l - CR^l ] _y Z wherein R^l and m are as previously described, y is a number in the range of about 2 to about 50, preferably about 2 to about 25, and each Z is a terminal group, e.g., hydrogen, a vinyl group. The vinyl ether

containing oligomers of Formula V can be blended with the other vinyl ether containing oligomers of the present invention or those disclosed in U.S. Patent Nos. 4,472,019; 4,749,807; 4,751,273; and 4,775,732.

The oligomers having an average of at least one electron-rich ethylenically unsaturated group per molecule of oligomer preferably contain an average of about 1 to about 10, more preferably about 2 to about 5, electron-rich ethylenically unsaturated groups per molecule of oligomer.

The number average molecular weight of the oligomers having an average of at least one electronrich ethylenically unsaturated group per molecule of oligomer is preferably about 500 to about 8,000, more preferably about 1,000 to about 4,000, daltons.

When the compositions of the present invention are utilized as a primary coating for optical glass fiber the equivalent weight of the oligomers having an average of at least one electron-rich ethylenically unsaturated group per molecule of oligomer is preferably about 500 to about 1,500, more preferably about 800 to about 1,200.

When the compositions of the present invention are utilized as a secondary coating for optical glass fiber the equivalent weight of the oligomers having an average of at least one electron-rich ethylenically unsaturated group per molecule of oligomer is preferably about 300 to about 1,000, more preferably about 400 to about 800.

The present compositions preferably contain the (meth) acrylate oligomer in an amount in the range of about 1 to about 70, more preferably about 20 to about 40, weight percent based on the total weight of the composition.

The present compositions preferably contain the single functionality diluent in an amount in the range of about 0 to about 40, more preferably about 5 to about 30, weight percent based on the total weight of the composition.

The present compositions preferably contain the dual functional monomer in an amount in the range of about 0 to about 40, more preferably about 5 to about 30, weight percent based on the total weight of the composition.

The present compositions preferably contain the saturated reactant in an amount in the range of about 0 to about 60, more preferably about 30 to about 50, weight percent based on the total weight of the composition.

The present compositions preferably contain the vinyl ether containing oligomer in an amount in the range of about 0 to about 50, more preferably about 10 to about 30, weight percent based on the total weight of the composition.

The viscosity of the present compositions is preferably about 200 to about 100,000, more preferably about 500 to about 4,000, centipoise (cP).

The compositions of the present invention are preferably solvent free.

The compositions of the present invention can be cured upon exposure to energy such as ionizing radiation, actinic energy, i.e., ultraviolet and visible light, and heat, i.e., thermal cure.

Conventional ionizing radiation sources include electron beam devices. The amount of ionizing radiation required for cure of a 3 mil thick film is about 1 to about 5 megarads.

When cure of this composition by exposure to actinic energy of appropriate wavelength, such as ultraviolet light, a photoinitiator can be admixed with the composition. The photoinitiator is preferably selected from the group consisting of (1) hydroxy- or alkoxy-functional acetophenone derivatives, preferably hydroxyalkyl phenones, and (2) benzoyl diaryl phosphine oxides. Materials having the two different types of ethylenically unsaturation, i.e., the vinyl ether group and the ethylenically unsaturated group, copolymerize rapidly in the presence of the specified groups of photoinitiators to provide a rapid photocure and also interact rapidly upon exposure to other types of energy when no polymerization initiator is present. Ethylenically unsaturated dicarboxylates respond poorly to photocure using, for example,

ultraviolet light when the photoinitiator is an ordinary aryl ketone photoinitiator, such as benzophenone. Also, the vinyl ethers do not exhibit any substantial curing response to ultraviolet light when these aryl ketone photoinitiators are utilized. Nonetheless, these two types of ethylenically unsaturated atoms in admixture respond to the photocure very rapidly when the

photoinitiator is correctly selected. The photocure, and the cure upon exposure to other types of energy when no initiator is present, is especially rapid and

effective when both of the described types of

unsaturation are provided in polyfunctional compounds, particularly those of resinous character. The fastest cures are obtained when the respective functionalities are present in about the same equivalent amount.

Preferred photoinitiators are (1) hydroxy- or alkoxy-functional acetophenone derivatives, more

preferably hydroxyalkyl phenones, and (2) benzoyl diaryl phosphine oxides.

The acetophenone derivatives that may be used have the Formula VI:

(VI)

in which R^m is an optional hydrocarbon substituent containing from 1 to 10 carbon atoms and which may be alkyl or aryl, e.g., methyl, ethyl, butyl, octyl or phenyl, X is selected from the group consisting of hydroxy, C₁ to C₄ alkoxy, C₁ to C₈ alkyl, cycloalkyl, halogen, and phenyl, or 2 Xs together are cycloalkyl, and at least one X is selected from the group consisting of hydroxy and C₁ to C₄ alkoxy.

Many compounds have the required structure.

The alkoxy groups are preferably methoxy or ethoxy, the alkyl group is preferably methyl or ethyl, the

cycloalkyl group is preferably cyclohexyl, and the halogen is preferably chlorine. One commercially

available compound is the Ciba-Geigy product Irgacure 651 which has the Formula VII:

(VII)

Irgacure 184, also from Ciba-Geigy, is another useful acetophenone derivative, and it has the Formula VIII:

(VIII)

Still another commercially available useful acetophenone derivative is diethoxy acetophenone, available from Upjohn Chemicals, North Haven, CT, which has the Formula IX:

(IX) When the photoinitiator is a

hydroxy-functional compound, one can define the useful acetophenone derivatives in a somewhat different manner. Thus, the hydroxyalkyl phenones which are preferred herein have the Formula X:

(X)

in which R^o is an alkylene group containing from 2-8 carbon atoms and Rⁿ is an optional hydrocarbon

substituent containing from 1 to 10 carbon atoms and which may be alkyl or aryl, e.g., methyl, ethyl, butyl, octyl or phenyl.

It is particularly preferred that the hydroxy group be in the 2-position in which case it is

preferably a tertiary hydroxy group which defines a hydroxy group carried by a carbon atom that has its remaining three valences connected to other carbon atoms. Particularly preferred compounds have the

Formula XI:

(XI)

in which each R^p is independently an alkyl group containing from 1 to 4 carbon atoms. In the commercial product Darocur 1173 available from E-M Company,

Hawthorne, N.Y., each R^p is methyl. This provides a compound which can be described as 2-hydroxy-2-methyl- 1-phenyl propane 1-one. The "propane" is replaced by butane or hexane to describe the corresponding

compounds, and these will further illustrate preferred compounds in this invention. The benzoyl diaryl phosphine oxide

photoinitiators which may be used herein have the

Formula XII:

In Formula XII, R^q is an optional hydrocarbon substituent containing from 1 to 10 carbon atoms and may be alkyl or aryl as previously noted, and each x is independently an integer from 1 to 3. In preferred practice, a 2,4,6-trimethyl benzoyl compound is used, and the two aromatic groups connected to the phosphorus atom are phenyl groups. This provides the compound 2,4,6-trimethyl benzoyl diphenyl phosphine oxide which is available from BASF under the trade designation Lucirin TPO.

When utilized, the photoinitiator is

preferably present in an amount in the range of about 0.01 to about 10.0, more preferably about 0.1 to about 6.0, weight percent based on the total weight of the composition.

Suitable sources of actinic energy includes lasers and other conventional light sources having an effective energy output, e.g., mercury lamps.

The wavelength of the actinic energy suitable for use herein extends from the ultraviolet range through the visible light range and into the infrared range. Preferred wavelengths are about 200 to about 2,000, more preferably about 250 to about 1,000, nanometers (nm).

The amount of actinic energy utilized to solidify a 3 mil thick film is about 0.05 to about 5.0, preferably about 0.1 to about 1, Joules per square centimeter (J/sqcm).

The compositions also can be thermally cured in the presence of a conventional thermal free-radical initiator, e.g., benzoyl peroxide, cyclohexanone

peroxide, N,N' azobis (isobutyrylnitrite), metallic dryer systems, redox systems, and the like.

The use of (meth) acrylate oligomers and the single functionality diluent and/or the dual functional monomer in the compositions of the present invention result in a reduction in toxicity as compared to

conventional compositions that contain only

(meth) acrylate oligomers and diluents. The

(meth) acrylate oligomers result in improved physical properties, e.g., toughness, abrasion resistance, tear resistance and flexibility in products produced from the compositions as compared to non (meth) acrylate

containing compositions. The reduction in toxicity and improved physical properties enhances the performance of the compositions of the present invention as coatings for optical glass fibers, coatings for substrates, e.g., glass, paper, wood, rubber, metal, concrete, fabric, and plastic, inks, flexigraphic printing plates, binders in the manufacturing of composites, and the like. The same results are achieved when the saturated reactant and/or vinyl ether containing oligomer are present in the compositions. The use of the (meth) acrylate oligomers in the compositions of the present invention also lowers the cost of these compositions as compared to similar compositions that do not utilize the (meth) acrylate oligomers.

The following Examples are preeent by way of representation, and not limitation, of the present invention. EXAMPLE 1: Preparation of the Dual Functional Monomer Into a one liter 4-neck flask were introduced 298.3 grams (g) (1.732 equivalents) of diethylmaleate, commercially available from Aldrich Chemical Co.,

Milwaukee, WI, 201.2 g (1.732 equivalents) of

4-hydroxybutyl vinyl ether (HBVE), commercially

available from GAF under the trade designation Rapicure HBVE, 0.5 g of tetraoctyl titanate, a conventional esterification cataylst commercially available from DuPont under the trade designation TYZOR TOT, and 0.22 g of phenothiazine, a conventional inhibitor commercially available from ICI Chemicals, Wilmington, DE. The flask was fitted with a variable speed stirrer, thermometers, a snyder column, a condenser with a trap, a nitrogen sparge and a heating mantle.

The temperature of the contents of the flask and the temperature at the top of the column, i.e., a thermometer is placed in the condenser at the top of the column to measure the temperature of distillate, were set to distill about 80 g of ethanol in a time period of about 2.5 hours. The resultant product was the dual functional monomer that had a viscosity at 25°C. of about 36 centipoise (cP). EXAMPLE 2: Compositions of the Present Invention

Compositions were prepared and tested. Each composition comprised a (meth) acrylate oligomer and at least one of a single functionality diluent and a dual functional monomer of EXAMPLE 1. The formulations of the compositions are present in TABLE I. TABLE I

Compositions

Composition

Equivalent

Component wt. A B C D E F G H I

Oligomer 1¹ 608 83.3 60.8 73.A - - - - - - - - - - - - - - - - - -

Oligomer2² 2030 - - - - - - - - - 92.4 81.9 82.9 - - - - - - - - -

Oligomer 3³ 2829 - - - - - - - - - - - - - - - - - - 80.3 - - - - - -

Cargill

15703⁴ Unreported - - - - - - - - - - - - - - - - - - - - - 75.0 75.0

DVE-3⁵ 101 13.8 10.1 16.3 4.6 8.2 4.1 2.9 8.0 2.5

Diethyl

maleate 172 - - - - - - 6.9 - - - 6.9 - - - - - - 13.6 4.3

Monomer⁶ 243 - - - 26.1 - - - - - - - - - 9.9 13.8 - - - 14.8

Photoinitiator 204 2.9 3.0 3.4 3.0 3.0 3.1 3.0 3.4 3.4

¹ The (meth) acrylate oligomer 1 of this Example.

2 The (meth) acrylate oligomer 2 of this Example

3 The (meth) acrylate oligomer 3 of this Example.

4 An acrylate oligomer that ls a diacrylate ester of Bisphenol A epichlorohydrin epoxide resin and is

commercially available from Cargill, Carpentersville, IL.

5 Triethyleneglycol divinyl ether commericially

available from GAF under the trade designation Rapicure

DVE-3.

⁶ The dual functional monomer of EXAMPLE 1.

7 Irgacure 184, commercially available from Ciba-Geigy Corp. Ardsley, NY.

(Meth) acrylate oligomer 1 was prepared by reacting 80.8 weight percent Adiprene L-200 commercially available from Uniroyal, Middlebury, CT, 0.1 weight percent of dibutyltin dilaurate, 0.1 weight percent butylated hydroxy toluene and 19 weight percent 2- hydroxyethyl acrylate. (Meth) acrylate oligomer 2 was prepared by reacting 3 mols of IDPI and 3 mols of 2-hydroxyethyl acrylate which was then reacted with 1 mol of Jeffamine T5000, commercially available from Jefferson Chemicals.

(Meth) acrylate oligomer 3 was prepared by reacting 18.65 weight percent Desmondur W, commercially available from Mobay Chemical Co., 0.01 weight percent P₂N, 0.03 weight percent butylated hydroxy toluene, 0.07 weight percent dibutyltin dilaurate and 35.9 weight percent NIAX PPG 1025 commercially available from Union Carbide which was then reacted with 4 weight percent hydroxyethyl acrylate which was then reacted with 30 weight percent phenoxyethyl acrylate, 7.3 weight percent N-vinyl pyrrolidone and 4 weight percent Jeffamine D230 commercially available from Jefferson Chemcials.

The results for tests conducted on Compositions A to I, and cured films prepared therefrom, are presented in TABLE II. The test procedures are presented after TABLE II.

TABLE II

Test Results

Property Composition: _A_ B C D E f

Appearance water yellow, water clear, clear, yellow, yellow, straw, yellow, white clear white very very very clear very clear slight slight slight slight

haze haze haze haze

Viscosity (cP) 12,200 2100 9200 8750 2900 4700 5000 8500 19,100

Tensile Properties

Tensile (MPA) 9.4 13 10 2.3 2.0 2.5 6.2 32 37

Elongation (%) 48 34 49 75 51 53 71 3.3 3.0

Modulus (MPa) 25 61 24 3.7 3.6 4.9 7.7 933 1113

Water absorption (%) -2.8 -1.4 -2.5 -1.4 -3.6 -1.0 -0.5 +1.9 ND¹

Water extractables

(%) -4.8 -2.8 -4.7 -1.9 -4.1 -2.1 -2.7 -0.7 ND

1 ND = Not determined.

The films, cured at a dosage of 1 Joule per square centimeter, prepared from Compositions A to I exhibited no odor. Films prepared from Compositions A, B and C were clear and exhibited no tack and good adhesion and toughness. Films prepared from

Compositions D, E and F exhibited slight tack. Film prepared from Composition G exhibited slight tack, good toughness and fair adhesion. Films prepared from

Compositions H and I exhibited no tack, were strong and stiff films.

Appearance

The appearance of the liquid composition was determined visually.

Viscosity

The viscosity, expressed in centipoise (cP), was measured using a Brookfield Model RVTD viscometer operated in accordance with the instructions provided therewith. The temperature of each sample tested was

25°C.

Tensile Properties

A film for determination of the tensile properties, i.e., tensile strength [Megapascals (MPa)], percent elongation at break (%) and modulus (MPa), of the coating was prepared by drawing down a 3 mil coating on glass plates using a Bird bar, commercially available from Pacific Scientific, Silver Springs, MD. An

automatic draw down apparatus like a Gardner AG-3860 commercially available from Pacific Scientific,

Gardner/Neotec Instrument Division, Silver Springs, MD, can be utilized. The coating was cured using a "D" lamp from Fusion Curing Systems, Rockville, MD. The "D" lamp emits radiation having a wavelength of about 200 to about 470 nanometers with the peak radiation being at about 380 nanometers and the power output thereof is about 300 watts per linear inch. The coating was cured at a dose of about 1 J/sqcm which provided complete cure. The film was then conditioned at 23 ± 2°C. and 50 ± 3% relative humidity for a minimum time period of 16 hours.

Six, 0.5 inch wide test specimens were cut from the film parallel to the direction of the draw down and removed from the glass plate. Triplicate measurements of the dimensions of each specimen were taken and the average utilized. The tensile properties of these specimens were then determined using an Instron Model 4201 from Instron Corp., Canton, MA operated in

accordance with the instructions provided therewith. Water Resistance

To determine the water resistance a 10 mil draw-down of the composition was made on a glass plate utilizing a Bird bar. The composition was cured utilizing the "D" lamp at a dose of 1.0 J/sqcm. Three test samples each having dimensions of 1/2" x 1" x 1/2" were cut from the cured coating. Each sample was weighed utilizing an analytical balance to obtain weight measurement A and then immersed in separate containers of deionized water. After a time period of 24 hours, the samples were removed from the water, blotted to remove excess water on the surface and reweighed to obtain weight measurement B. The samples were then placed in aluminum pans and maintained therein at ambient conditions, i.e., ambient temperature (about 20° - 30°C.) and ambient humidity, for a time period of 120 hours. The samples were then reweighed to obtain weight measurement C. The following equations were utilized to calculate the water absorption and the extractables.

(I) % water absorption = [ (B - A) /A] x 100

(II) % extractables = [ (C - A) /A] x 100 It is preferably to have relatively low % water absorption and % extractables.

A negative value obtained for % water absorption indicates water soluble, low molecular weight materials were leached out of the film.

EXAMPLE 3: Toxicity Studies

Toxicity tests were performed on commercially available (meth) acrylate oligomers and diluents and on commercially available vinyl ether and maleate diluents. The results of these toxicity tests are provided in TABLE III. TABLE III

Toxicity Tests

Inhalation Skin Eye

Oral LD₅₀ Skin LD₅₀ Kill Irritation Irritation

Material (mg./kg.) (mg . /kg . ) (animals) (max.=8) (max.=10)

ACTOMER

X-70¹ 23.8 16 0 of 6 2 1

ACTOMER

X-80¹ 20 16 0 of 6 3 1

Neopentylglycol

diacrylate² 5.19 0.35 1 of 6 5 8

2-hydroxyethyl

acrylate 0.65 0.14 1 of 6 6 9

Pentaerythritol

triacrylate 2.46 0 of 6 2 10

2-phenoxyethyl

acrylate 4.66 2.54 0 of 6 3 1

Diethyleneglycol

diacrylate 0.77 0.18 0 of 6 5 9

1,6-hexanediol

diacrylate 4.76 0.71 0 of 6 3 2

Triethyleneglycol

divinyl

ether 7500 72000 NA³ 0.25 none

Dimethyl

maleate 1410 530 NA 5.47 moderate

Diethyl

maleate 3200 4000 NA mi ld mi ld

Dibutyl

maleate 8530 16000 NA mi ld NA

¹ The Actomer products, commercially available from Union Carbide, are acrylate oligomers prepared by the addition of acrylic acid to epoxidized soy or linseed oils. These are relatively high molecular weight materials containing up to three to six acrylic groups respectively per molecule.

² Neopentylglycol diacrylate was found to be an

experimental tumor causing agent.

³ NA = Not available.

The skin irritation and eye irritation tests were conducted according to the procedure to catagorize the compositions under the Federal Hazardous Substance

Labeling Act (16 C.F.R. §1500).

A composition representing the present invention (Composition J) was tested for skin irritation and eye irritation. The test results are presented in TABLE IV, below.

TABLE IV

Toxicity Study of Compositions

Composition Skin irritation (PI)¹ Eye irritation

J 1.8 non-irritant

¹ PI = Primary irritation index. A PI of 1.8 indicates the composition of the present invention (Composition J) is only a mild irritant.

TABLE IV indicates that the present compositions result in a significant reduction in irritation as compared to conventional (meth) acrylate compositions.

The reactant, a branched maleate terminated ester, of Composition J was prepared utilizing a glass flask equipped with a reflux condenser, Dean-Stark tube for azetropic separation of water, a heating mantle, a thermometer, and a mechanical stirrer. A mixture of maleic anhydride (0.8 mols) and butyl carbitol (0.84 mols) was heated in the flask to 80ºC. An exothermic reaction occurred and the temperature rose to 120ºC.

where it was held for a time period of 2 hours.

Trimethylol propane (0.23 mols), 1,6-pentane diol (0.3 mols), azelaic acid (0.2 mols), Fascat 4100 a catalyst commercially available from M & T Chemical Co. (0.3%) and 40 ml of xylene were then added to the flask. The contents of the flask were heated and stirred while the water of reaction was removed by azetropic distillation. When an acid value of 16.5 was reached, the xylene was distilled out. The resulting branched maleate

terminated ester had a Brookfield viscosity of 392 cP.

Composition J comprised Novacure 8805, a urethane acrylate oligomer commercially available from Interez Inc., Louisville, KY (40 parts), Rapicure DVE-3, commercially available from GAF (14.7 parts), the maleate terminated ester described above (55.9 parts), Darocur 1173, commercially available from E & M Company (5.0 parts), and Phenothiazine, commercially available from Eastman (0.2 parts) were blended together at room temperature under yellow safety lights until

homogeneous. The resultant Composition J had a

viscosity of 1,830 cP, a weight per gallon of 8.6 pounds, and a closed cup flash point of greater than 212ºF.

Composition J was drawn down on a paper sheet with a # 20 wire wound rod, placed on a U.V. cure apparatus (commercially available from Fusion Systems) to cure. At an exposure of 1 Joule/square centimeter, the resultant coating was completely cured (125+ MEK Double rubs) with a tough hard surface. The same coating cured with 5 megarads of electron beam exposure. Removal of the Darocur 1173 from Composition J permitted much lower electron beam doses for total cure (about 2-3 megarads). EXAMPLE 4: Comparison of Compositions

A (meth) acrylate oligomer containing composition (Composition K) was compared to a similar composition that did not include a (meth) acrylate oligomer

(Composition L). The formulations of Compositions L and M are provided in TABLE V.

TABLE V

Compositions

Component Composition (wt) : K

Novacure 8805¹ 36.2 - - -

Saturated

Reactant 1² - - - 76.9

Saturated

Reactant 2³ 50.5 - - -

DVE-3⁴ 13.3 19.2

Photoinitiator⁵ 5.0 3.9.

Phenothiazine 0.2 - - -

¹ A urethane acrylate oligomer commercially available from Interez, Inc., Louisville, KY.

² Saturated Reactant 1 of this EXAMPLE.

³ Saturated Reactant 2 of this EXAMPLE.

4 Triethyleneglycol divinyl ether commercially available from GAF under the trade designation Rapicure DVE-3. 5 Darocur 1173, commercially available from E-M Company, Hawthorne, NY. Saturated Reactant 1 was prepared by reacting the diisocyanate commercially available under the trade designation Desmodur W with the butyl cellosolve ester of maleic anhydride which had been reacted with

propylene oxide. Saturated Reactant 2 was prepared by reacting 1,5 pentane diol and maleic anhydride followed by

reacting butyl carbitol therewith.

Properties of Compositions L and M, and coatings produced therefrom, were tested and the results are provided in TABLE VI.

TABLE VI

Test Results

Property Composition: K L

Viscosity (cP) 1,830 3,500

MEK Double Rubs

Cure dose: 0.5 J/sqcm >200 175

1.0 J/sqcm >200 181

Adhesion to

Polycarbonate

substrate (%) 0 0

Flexibility Stiff Stiff with

slight

flexibility

Flask point >212°F 163ºF

Eye irritation non- nonirritant irritant

Skin irritation (PI) 1.8 2.3

(mild) (moderate)

The procedures for determining viscosity, eye irritation and skin irritation have been previously discussed.

The MEK Double Rubs test consists of curing a film of the composition at a cure dose of either 0.5 J/sqcm or 1 J/sqcm. The surface of the film was then rubbed with a cloth soaked in methyl ethyl ketone (MEK). A section of the surface was rubbed in one direction and then in the opposite direction over the same section to constitute one double rub. The number provided is the number of the double rub at which deterioration of the film was first noted. The adhesion to a polycarbonate substrate was determined by curing a film of the composition on the substrate at a cure dose of 1 J/sqcm.

A first adhesion test was conducted by making a cross hatching of 10 parallel cuts, equally spaced apart, in the film down to the substrate. Then, 10 parallel cuts, also equally spaced apart, were made perpendicular to the first 10 cuts. The cut section was then covered with Scotch brand 610 tape commercially available from 3M Company that adhered to the surface. The tape was removed and the number of squares of film remaining adhered to the substrate is the percent adhesion. None of the film adhered to the substrate.

A second adhesion test was conducted but no cuts were made in the film. Again, none of the film remained adhered to the substrate

The adhesion and flexibility of these

compositions can be improved by reducing the cross-link density of the cured films. This reduction can be achieved by increasing the amount of single

functionality diluent and/or dual functional monomer utilized.

EXAMPLE 5: Paper Coating Compositions

Compositions suitable as paper coating compositions were prepared and tested. The formulations of these compositions are presented in TABLE VII.

TABLE VII

Paper Coating Compositions

Component Composition (wt) M N O

Reactant¹ 63.9 63.9 63.9

DVE-3² 23.0 23.0 23.0

Diethyl maleate 13.1 13.1 13.1

Photoinitiator³ 7.0 7.0 7.0

Phenothiazine 0.1 0.1 0.1

N-vinyl pyrrolidone 5.0 - - - - - - DEA⁴ 4.0 4.0 4.0

AM 1908⁵ - - - 10 - - -

DC 57⁶ 0.5 0.5 0.5

¹ The product of the reaction of trishydroxyethyl isocyanurate with the butyl carbitol ester of maleic anhydride.

2 Triethyleneglycol divinyl ether commercially available from GAF under the trade designation Rapicure DVE-3.

³ Darocur 1173, commercially available from E-M Company, Hawthorne, NY.

⁴ Diethyl amine.

5 An acrylate-terminated melamine derivative

commercially available from Monsanto under the trade designation Santolink AM 1908.

⁶ A surfactant available from Dow Corning. The Compositions N to P, and films produced therefrom, were tested. The test results are provided in TABLE VIII.

TABLE VIII

Test Results

Property Composition: M N O

Viscosity (cP) 140 240 210

Adhesion to Paper Substrate:

610 100 100 100

610 Crosshatch 95 85 95

Scotch 100 95 100

MEK Double Rubs

cure dose: 0.5 J/sqcm 64 100 69

1 J/sqcm 60 107 85

The test procedure for determination of the viscosity has been discussed previously

The adhesion to a paper substrate tests was similar to the previously discussed adhesion test. The cure dose for these adhesion test was 0.5 J/sqcm.

Furthermore, a third adhesion test was conducted using scotch tape on an uncross-hatched film.

The MEK Double Rubs test was conducted on a film cured to an aluminum Q panel.

Claims (37)

WE CLAIM:

1. Free-radical curable compositions

comprising a (meth) acrylate oligomer and at least one of a single functionality diluent, a mixuture of single functionality diluents, and a dual functional monomer, wherein the ratio of electron-rich double bonds to electron deficient double bonds in the compositions is in the range of about 5:1 to about 1:5.

2. The compositions in accordance with claim 1 wherein the ratio of electron-rich double bonds to electron deficient double bonds is about 2:1 to about 1:2.

3. The compositions in accordance with claim 1 wherein the ratio of electron-rich double bonds to electron deficient double bonds is about 1:1.

4. The compositions in accordance with claim 1 wherein the (meth) acrylate oligomer has a number average molecular weight of about 1,000 to about 15,000 daltons.

5. The compositions in accordance with claim 1 wherein the (meth) acrylate oligomer has a number average molecular weight of about 1,200 to about 6,000.

6. The compositions in accordance with claim 1 wherein the dual functional monomer has the Formula:

wherein R^a is selected from the group consisting of H, C₁ to C₁₀ alkyl or allyl groups, C₅ to C₁₀ aryl groups, metal ions, heteroatoms and combinations of carbon and heteroatoms; R^b is absent or selected from the group consisting of O, C(R^a)₂, heteroatoms, or substituted heteroatoms; R^c is an aliphatic, branched or cyclic alkyl group or an arylalkyl group that contains 1 to about 10 carbon atoms, and can contain heteroatoms; and Y is selected from the group consisting of:

wherein each R^d is independently selected from the group consisting of H, C₁ to C₄ alkyl groups, C₅ to C₁₀ aryl groups and electron withdrawing groups.

7. The compositions in accordance with claim 6 wherein R^a is a C₁ to C₄ alkyl group, R^b is O, R^c is a C₂ to C₈ alkyl group and each R^d is H.

8. A substrate coated with a composition of claim 1.

9. The coated substrate in accordance with claim 8 wherein the substrate is selected from the group of glass, paper, wood, rubber, metal, concrete, leather, fabric, and plastic substrates.

10. A substrate coated with a cured composition of claim 1.

11. The compositions in accordance with claim 1 that comprise the (meth) acrylate oligomer and the single functionality diluent.

12. The compositions in accordance with claim 1 that comprise the (meth) acrylate oligomer and the dual functional monomer.

13. The compositions in accordance with claim 1 that comprise the (meth) acrylate oligomer, the single functionality diluent and the dual functional monomer.

14. The compositions in accordance with claim 1 that further comprise at least one of an oligomer having an average of at least one electron-rich ethylenically unsaturated group per molecule of oligomer and a

reactant having a saturated backbone and at least one electron deficient ethylenically unsaturated end group per molecule of reactant.

15. The compositions in accordance with claim 14 wherein the (meth) acrylate oligomer has a number average molecular weight of about 1,000 to about 15,000 daltons.

16. The compositions in accordance with claim 14 wherein the (meth) acrylate oligomer has a number average molecular weight of about 1,200 to about 6,000 daltons.

17. The compositions in accordance with claim 14 wherein the oligomer having an average of at least one electron-rich ethylenically unsaturated group has an average of about 1 to about 10 electron-rich

ethylenically unsaturated groups per molecule and the reactant has an average of about 1 to about 10 electron deficient ethylenically unsaturated end groups per molecule.

18. The compositions in accordance with claim 14 wherein the oligomer having an average of at least one electron-rich ethylenically unsaturated group has an average of about 2 to about 5 electron-rich

ethylenically unsaturated groups per molecule and the reactant has an average of about 2 to about 5 electron deficient ethylenically unsaturated end groups per molecule.

19. The compositions in accordance with claim

14 wherein the ratio of electron-rich double bonds to electron deficient double bonds is about 2 : 1 to about 1:2.

20. The compositions in accordance with claim

14 wherein the ratio of electron-rich double bonds to electron deficient double bonds is about 1:1.

21. The compositions in accordance with claim 14 wherein the dual functional monomer has the Formula:

wherein R^a is selected from the group consisting of H, C₁ to C₁₀ alkyl or allyl groups, C₅ to C₁₀ aryl groups, metal ions, heteroatoms and combinations of carbon and heteroatoms; R^b is absent or selected from the group consisting of O, C(R^a)₂, heteroatoms, or substituted heteroatoms; R^c is an aliphatic, branched or cyclic alkyl group or an arylalkyl group that contains 1 to about 10 carbon atoms, and can contain heteroatoms; and Y is selected from the group consisting of: wherein each R^d is independently selected from the group consisting of H, C₁ to C₄ alkyl groups, C₅ to C₁₀ aryl groups and electron withdrawing groups.

22. The compositions in accordance with claim

21 wherein R^a is a C₁ to C₄ alkyl group, R^b is O, R^c is a C₂ to C₈ alkyl group and each R^d is H.

23. The compositions in accordance with claim 14 that further comprise a photoinitiator.

24. A substrate coated with a composition of claim 14.

25. The coated substrate in accordance with claim 24 wherein the substrate is selected from the group of glass, paper, wood, rubber, metal, concrete, leather, fabric and plastic substrates.

26. A substrate coated with a cured composition of claim 14.

27. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer; the single functionality diluent ; and the oligomer having an average of at least one ethylenically unsaturated group.

28. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer; the single functionality diluent; and the reactant.

29. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer; the dual functional monomer; and the oligomer having an average of at least one ethylenically unsaturated group.

30. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer; the dual functional monomer; and the reactant.

31. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer, the single functionality diluent, the dual functional monomer, and the oligomer having an average of at least one

ethylenically unsaturated group.

32. The composition in accordance with claim 14 that comprise the (meth) acrylate oligomer, the single functionality diluent, the dual functional monomer, and the reactant.

33. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer, the single functionality diluent, the oligomer having an average of at least one ethylenically unsaturated group, and the reactant.

34. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer, the dual functional monomer, the oligomer having an average of at least one ethylenically unsaturated group, and the reactant.

35. The compositions in accordance with claim 14 that comprise the (meth) acrylate oligomer, the single functionality diluent, the dual functional monomer, the oligomer having an average of at least one ethylenically unsaturated group, and the reactant.

36. The compositions in accordance with claim

14 wherein the electron-rich ethylenically unsaturated group is a vinyl ether group.

37. The compositions in accordance with claim 14 wherein the electron deficient ethylenically

unsaturated group is a dicarboxylate group.