JP2007511641A - Binary curing reaction product of self-initiated polyfunctional acrylate and alicyclic epoxy compound - Google Patents

Abstract

  A photopolymerizable liquid oligomer composition is disclosed. The oligomer composition was synthesized from polyfunctional acrylates and β-dicarbonyl Michael donors, particularly β-ketoesters, β-diketones, β-ketoamides, or β-ketoanilides, or combinations thereof. It is formed from a Michael addition polyacrylate resin and alicyclic epoxides. The oligomer compositions are provided along with their use and manufacturing methods.

Description

  The present invention generally relates to a photopolymerizable resin. The present invention particularly relates to an oligomer composition comprising an alicyclic epoxide compound and a polyfunctional acrylate and a polyfunctional acrylate oligomer synthesized from a β-ketoester, β-diketone, β-ketoamide or β-ketoanilide.

  The information presented below is not admitted to be prior art to the present invention, but is merely provided to aid the reader's understanding.

  Acrylate, methacrylate, and other unsaturated monomers are widely used in coatings, adhesives, sealants, and elastomers and can be crosslinked by ultraviolet light in the presence of a photoinitiator or by peroxide initiated free radical curing. These photoinitiators and / or peroxides are typically low molecular weight polyfunctional compounds that can be volatile or easily absorbed from the skin and can cause adverse health effects. Functionalized oligomeric photoinitiators can overcome some of these drawbacks; typically polymeric photoinitiators are non-volatile compounds and are not easily absorbed from the skin. However, multi-step synthesis is required, low functionality may be detrimental to reactivity and final properties, and catalysts or initiators may still be needed to crosslink.

  Michael addition of acetoacetate donor compounds to multivalent acrylate acceptor compounds has been described in the literature. For example, Mozner and Rheinberger reported the Michael addition of acetoacetate to triacrylate and tetraacrylate (16 Macromolecular Rapid Communications 135 (1995)). The product formed was a crosslinked gel. As depicted in FIG. 1, in one such reaction, Mozner uses three functional groups of trimethylolpropane triacrylate per mole of polyethylene glycol (molecular weight 600) (PEG 600-DAA) having two functional groups. 1 mole of (TMPTA) was added. (Each acetoacetate “functional group” reacts twice and each mole of diacetoacetate has 4 reaction equivalents.) The resulting network is a “gel, despite the presence of unreacted acrylic functionality. Or “hardened”. While further reaction can proceed, this network cannot be liquefied either by heat or solvent. This is because it is substantially cross-linked.

  The above reaction can be characterized by various ratios to describe the reactants: TMPTA: PEG600DAA = 1: 1, acrylate number to acetoacetate functional group ratio = 3: 2, and reactive equivalent ratio = 3: 4.

Moy et al., US Pat. Nos. 5,945,489 and 6,025,410, assigned to Ashland, the assignee of the present invention, disclose certain soluble liquid uncrosslinked oligomers. Is made by a one-step Michael addition of a β-dicarbonyl donor compound (eg, acetoacetate) to a polyfunctional acrylate and can be further crosslinked using ultraviolet light without the need for expensive photoinitiators. The disclosed oligomer can be described as a self-photoinitiated acrylate resin. In addition, when the correct proportion of polyfunctional acrylate acceptor compound is coupled to the β-dicarbonyl donor compound in the presence of a basic catalyst, a liquid oligomer composition results. If a proportion below the range disclosed in the above cited patent document is used, a crosslinked gel or solid product is produced. In addition, the disclosed liquid oligomer composition can be easily applied to various substrates using conventional coating techniques, such as rolls or sprays, prior to UV curing.
US Pat. No. 5,945,489 US Pat. No. 6,025,410 Mozner and Rheinberger, 16 Macromolecular Rapid Communications 135 (1995) The Encyclopedia of Polymer Science and Engneering, 2nd edition, Wiley-International Publication (1985)

  The term “monomer” is used herein to refer to a molecule or compound that contains carbon, has a relatively low molecular weight, has a simple structure, and is combined with other similar and / or dissimilar molecules or compounds. And can be converted to polymers, synthetic resins or elastomers.

  The term “oligomer” is defined herein as a polymer molecule consisting of only a few similar and / or dissimilar monomer units.

  The term “resin” is defined herein as an oligomer that can be converted to a high molecular weight polymer by combination with other similar and / or dissimilar molecules or compounds.

  The term “thermoset” is defined herein as a high molecular weight polymer product of a resin that solidifies or cures irreversibly when heated.

Co-pending application assigned to the assignee of the present invention, Attorney Docket No. 20435/0141 (
Which is expressly incorporated by reference in its entirety, discloses a dual-cured thiolene system comprising a self-initiated acrylate resin crosslinked with a polyfunctional thiol.

  The use of acrylate-based resin systems is limited by their relatively poor adhesion to metal substrates. Adhesion to metals can be enhanced by using cationically cured aliphatic epoxy compounds.

[Summary of the present invention]
In the presence of a suitable cationic initiator, the addition of a suitable alicyclic epoxide to the polyacrylate resin disclosed above results in better surface hardening with increased adhesion, hardness, and abrasion resistance We disclose to provide a coating having

  The present invention provides a binary curable polymerizable resin composition. Coatings, adhesives, sealants, and inks can be made using the resins of the present invention that cure by two different mechanisms. The first mechanism is UV initiated free radical polymerization of Michael addition resins with pendant acrylate functionality. The second mechanism, so-called cationic curing, results in UV-initiated acid polymerization of epoxy resins catalyzed by strong acids generated by light. In this cationic curing process, the cationic photoinitiator is cleaved by UV light, producing a strong Lewis acid or a strong Bronsted acid. The cationic photoinitiator is preferably a perfluorometalate onium salt.

  The present invention provides a liquid oligomer composition comprising a bifunctional alicyclic epoxide; and an organic soluble, non-gelled, uncrosslinked Michael addition resin, the Michael addition resin comprising a multifunctional acrylate Michael acceptor. And a β-dicarbonyl Michael donor (particularly, β-ketoester, β-diketone, β-ketoamide, cyanoacetate, or β-ketoanilide, or a combination thereof).

  It has a storage stability of more than a month and has residual pendant unsaturated acrylate groups (as opposed to unsaturation in the oligomer "backbone", as obtained in the production of unsaturated polyester resins), which is also UV The present invention provides a liquid oligomer composition that photopolymerizes very quickly upon exposure to radiation.

  The present invention is selected from the group consisting of pigments, gloss modifiers, flow and leveling agents, and other additives suitable for formulating coatings, paints, laminates, sealants, adhesives, and inks. A liquid oligomer composition optionally further comprising at least one additive. An excellent general reference disclosing such additives is The Encyclopedia of Polymer Science and Engneering, 2nd edition, Wiley-International Publication (1985).

  The present invention provides a method of making a liquid oligomer composition having residual pendant unsaturated acrylate groups, the method comprising the following steps: providing a multifunctional acrylate Michael acceptor and a β-dicarbonyl Michael donor Reacting the donor with the acceptor to form a Michael adduct using a base catalyst; adding an acidifying agent to neutralize all remaining basic species, at least one Mixing the alicyclic epoxides.

  In one aspect of the invention, a liquid oligomer composition is provided that further comprises at least one modifying epoxide. The modifying epoxide is selected to improve the film properties of the cured coating (eg, to reduce adhesion of the metal and / or the viscosity of the coating for application purposes). The present Michael polyacrylate resin / epoxide binary curing system can develop "green strength" or "blocking resistance" with a few UV pulses or traces of amine or peroxide catalyst. Once the first stage of curing or the initial extent of curing is achieved, the coating can then be processed by molding, printing, or laminating operations prior to full curing. Thus, the ability of binary curing allows the substrate to be manipulated in ways that conventional systems, including conventional UV curable coatings, could not mimic.

  The present invention relates to a method for using a liquid oligomer composition comprising an alicyclic epoxide and an organic, non-gelled, uncrosslinked Michael addition polyacrylate reaction product, wherein the oligomer composition is applied to a surface. And a method comprising curing the composition in the presence of a cationic photoinitiator and actinic radiation.

  One aspect of the present invention provides a thermoset formed from the oligomer composition of the present invention.

  The present invention provides that the composition comprises pigments, gloss modifiers, fluidizers and leveling agents, and other additives suitable for formulating coatings, paints, laminates, sealants, adhesives, and inks. Provided is a method of using a liquid oligomer composition further comprising at least one additive selected from the group.

  Certain aspects of the present invention provide oligomeric compositions that can be further crosslinked to create coatings (eg, paints, varnishes), inks, laminates, sealants, adhesives, elastomers, and composite matrices.

  The present invention provides a polymerized product comprising an alicyclic epoxide and an organic soluble, non-gelled, uncrosslinked Michael addition polyacrylate reaction product, further crosslinked in the presence of a cationic photoinitiator.

[Explanation of drawings]
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that according to typical practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.
The accompanying drawings illustrate only typical embodiments of the invention and should not be considered as limiting the scope of the invention as the invention allows other similar effective embodiments. You should be careful.

Detailed Description of Preferred Embodiments
Reference is made to the figures to illustrate selected embodiments and preferred methods of practicing the invention. It should be understood that the invention is not limited to the aspects depicted in the figures.

  One aspect of the invention is a liquid oligomer composition comprising a controlled proportion mixture of an alicyclic epoxide, a cationic photoinitiator, and an organic soluble, non-gelled, non-crosslinked Michael addition polyacrylate reaction product. I will provide a. The Michael addition polyacrylate oligomer is formed from a multifunctional acrylate Michael acceptor and a β-dicarbonyl Michael donor. The β-dicarbonyl Michael donor is suitably selected from among β-ketoesters, β-diketones, β-ketoamides, and β-ketoanilides. The multifunctional acrylate Michael acceptor is suitably selected from diacrylates, triacrylates, and tetraacrylates. The breadth of the β-dicarbonyl donor and the multifunctional acrylate acceptor provides the composition designer with the opportunity to use greater breadth of selectivity in the properties of the final product.

  Preferred diacrylates include, but are not limited to: ethylene glycol diacrylate, propylene glycol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate , Tetrapropylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxylated bisphenol A diacrylate, bisphenol A diglycidyl ether diacrylate, resorcinol diglycidyl ether diacrylate, 1,3-propanediol diacrylate, 1, 4-butanediol diacrylate, 1 5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, cyclohexane dimethanol diacrylate, ethoxylated neopentyl glycol diacrylate, propoxylated neopentyl glycol diacrylate, ethoxylated cyclohexane dimethanol Diacrylate, propoxylated cyclohexanedimethanol diacrylate, epoxy diacrylate, aryl urethane diacrylate, aliphatic urethane diacrylate, polyester diacrylate, and mixtures thereof.

  Preferred triacrylates include, but are not limited to: trimethylolpropane triacrylate, glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, tris (2-hydroxyethyl) isocyanurate tri Acrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, pentaerythritol triacrylate, aryl urethane triacrylate, aliphatic urethane triacrylate, melamine triacrylate, epoxy novolac triacrylate, aliphatic epoxy triacrylate, polyester triacrylate, And mixtures thereof.

  Preferred tetraacrylates include, but are not limited to: ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, ethoxylated dipentaerythritol. Tetraacrylate, propoxylated dipentaerythritol tetraacrylate, aryl urethane tetraacrylate, aliphatic urethane tetraacrylate, polyester tetraacrylate, melamine tetraacrylate, epoxy novolac tetraacrylate, and mixtures thereof.

  In a preferred embodiment, the β-dicarbonyl Michael donor is a β-diketone (eg, 2,4-pentanedione). Suitably, the present invention also provides a β-ketoester (eg, ethyl acetoacetate), β-ketoanilide (eg, acetoacetanilide), or β-ketoamide (eg, acetoacetamide), depending on the desired resin quality and end use. Alternatively, it can be carried out with a Michael donor mixture. In a preferred embodiment of the invention, β-dicarbonyl has functionality (N) (N = 2). Higher functionality (ie, N = 4, 6 ...) β-dicarbonyl donors are suitable, but more careful reaction stoichiometry control must be used to avoid undesired gelation of the system. I must.

  Suitable β-dicarbonyl donor compounds having functionality = 2 include, but are not limited to: ethyl acetoacetate, methyl acetoacetate, 2-ethylhexyl acetoacetate, lauryl acetoacetate, t-butyl acetoacetate , Acetoacetanilide, N-alkylacetoacetanilide, acetoacetamide, 2-acetoacetoxylethyl acrylate, 2-acetoacetoxylethyl methacrylate, allyl acetoacetate, benzyl acetoacetate, 2,4-pentanedione, isobutyl acetoacetate, and 2 -Methoxyethyl acetoacetate.

  Suitable β-dicarbonyl donor compounds having functionality = 4 include, but are not limited to: 1,4-butanediol diacetate, 1,6-hexanediol diacetate, neopentyl glycol diacetate Acetate, cyclohexane dimethanol diacetate, and ethoxylated bisphenol A diacetate.

  Suitable β-dicarbonyl donor compounds having functionality = 6 include, but are not limited to: trimethylolpropane triacetoacetate, glycerin triacetoacetate, and polycaprolactone triacetoacetate.

  A suitable but non-limiting β-dicarbonyl donor compound with functionality = 8 is pentaerythritol tetraacetoacetate.

  The Michael addition reaction is catalyzed by a strong base. A preferred base is diazabicycloundecene (DBU), which is strong enough and readily soluble in the monomer mixture. Other cyclic amidines such as diazabicyclononene (DBN) and guanidines are also suitable for catalyzing this polymerization. Group I alkoxide bases, such as potassium tert-butoxide, are usually suitable for facilitating the desired reaction if they have sufficient solubility in the reaction solvent. Quaternary hydroxides and alkoxides, such as tetrabutylammonium hydroxide or benzyltrimethylammonium methoxide, constitute another group of preferred base catalysts for promoting the Michael addition reaction. Finally, strong, organophilic alkoxide bases can be generated in situ by reaction between halogen anions (eg, quaternary halides) and epoxide groups. Such in situ catalysts are disclosed in pending application 10 / 255,541 assigned to Ashland Inc., the assignee of the present application. The entire contents of application 10 / 255,541 are hereby incorporated by reference in their entirety.

  Michael addition of a methacrylate functional β-dicarbonyl compound (eg, 2-acetoacetoxyethyl methacrylate (AAEM)) to a diacrylate monomer produces a liquid polyacrylate with reactive pendant methacrylate groups, which It can be crosslinked in the curing reaction. Since the acrylate and acetoacetate are mutually reactive and the methacrylate is substantially inert under the conditions of the desired Michael addition reaction, it is highly functionalized (one methacrylate per repeat unit), liquid Uncrosslinked oligomers can be obtained in one step, at room temperature and without solvent reaction.

The present invention provides the advantage of not requiring a solvent. However, the high selectivity of the Michael reaction allows the use of monomers such as styrene and methyl methacrylate as inert solvents to provide a low viscosity system that is easily incorporated into various laminating resins. Suitable non-reactive solvents include, but are not limited to, styrene, t-butyl styrene, α-methyl styrene, vinyl toluene, vinyl acetate, allyl acetate, allyl methacrylate, diallyl phthalate, C _1- C ₁₈ -methacrylic acid ester, dimethacrylate, and trimethacrylate are included.

  The present invention provides a resin having residual pendant unsaturated acrylate groups. Residual pendant unsaturated groups mean that polymerizable acrylic groups are retained by carefully controlling the stoichiometry of the reactants. That is, there are more acrylic groups than reactive sites on the Michael donor. The nature of the addition reaction leaves a pendant acrylic group away from the site of Michael addition (as opposed to the pendant being present as part of the “backbone” of the structure attached on the two sides). Pendant acrylic groups can be used for free radical polymerization, further Michael addition cross-linking or “pseudo Michael addition” reactions with, for example, amines. The pseudo-Michael addition reaction by thiol-ene addition with mercaptan in UV irradiation is disclosed in co-pending application Attorney Docket 20435/0141, the entire disclosure of which is practically specifically incorporated by reference. The pendant acrylate group of the Michael polyacrylate resin can also be utilized to crosslink by a free radical mechanism in the presence of a strong acid generating cationic photoinitiator because free radicals are also formed by the photolysis process.

  In the following examples, all parts are by weight (mass) unless otherwise specified.

  An example of the synthesis of a Michael polyacrylate resin (also referred to as Michael oligomer, Michael adduct, or Michael addition product) is shown in FIG. 59.2 g of trimethylolpropane triacrylate (TMPTA) and 0.4 g of diazabicycloundecene (DBU) were weighed into a 500 ml three neck round bottom flask equipped with a mechanical stirrer and dropping funnel. 13.0 g of ethyl acetoacetate (EAA) was weighed into a dropping funnel. TMPTA and DBU were mixed for 5 minutes prior to the addition of EAA. EAA was then added dropwise over 15 minutes to the stirred TMPTA / DBU mixture. After the addition of EAA was complete, the solution was warmed to 54 ° C. After the exotherm had subsided in 100 minutes, a viscous yellow liquid was obtained. This did not gel upon standing.

  The same general method can be used for various combinations of acrylates and β-dicarbonyl Michael donors provided that the equivalent ratio of acrylate: Michael donor is sufficient to produce a liquid uncrosslinked product. it can. Especially for exothermic or large-scale reactions, controlled stepwise addition of Michael donors and / or cooling of the reaction is necessary to prevent premature, heat-initiated crosslinking of the acrylate functionality. It can be said.

  One aspect of the present invention provides a dual cure mechanism. An alicyclic epoxide compound is added to the Michael acrylate resin along with a suitable cationic photoinitiator. Cationic photoinitiators are onium compounds that photodegrade when excited by ultraviolet (UV) light. Photolysis of various onium species yields Lewis or Bronsted acids. (Koleske, J.V., Radiation Curing of Coatings, ASTM Manual 45, (2002)). As part of the photolysis process, free radicals are formed that can catalyze the polymerization of ethylenically unsaturated groups present in the resin. Polymerization of epoxides with ethylenically unsaturated compounds is catalyzed by strong acids dissociated by photolysis of onium photoinitiators.

  The cationic photoinitiator of the present invention is an onium salt that decomposes to produce a strong acid when irradiated with UV. More specifically, photoinitiators include arylsulfonium metal salts, aryliodonium metal salts, and arylphosphonium metal salts. These and other cationic photoinitiators are described in G. Bradley, Wiley / SITA Series in Surface Coatings Technology, Vol. III, John Wiley and Sons Ltd., Chichester, England, 1998, p.329, JVCrivello and K. It is included in Chapter III of “photoinitiators for Cationic Polymerisation” by Dietliker. It is understood that the cited onium salts are non-limiting examples of suitable and preferred cationic photoinitiators. Those skilled in the art are familiar with other suitable cationic photoinitiators or will be able to determine them with minimal experimentation.

  An example of an arylsulfonium cation is a triarylsulfonium (eg, triphenylsulfonium) cation. The triarylsulfonium cation has been found to exist as a complex mixture of arylsulfonium salts. The term “triarylsulfonium” is used herein to mean a complex mixture of arylsulfonium species and / or any one of such species.

  An example of an aryl iodonium cation is a diaryl iodonium (eg, diphenyl iodonium) cation. The diaryliodonium cation has been found to exist as a complex mixture of diaryliodonium salts. The term “diaryliodonium” is used herein to mean a complex mixture of aryliodonium species and / or any one of such species.

  An example of an arylphosphonium cation is a tetraarylphosphonium (eg, tetraphenylphosphonium) cation. The tetraarylphosphonium cation has been found to exist as a complex mixture of tetraarylphosphonium salts. The term “tetraarylphosphonium” is used herein to mean a complex mixture of arylphosphonium species and / or any one of such species.

The undissociated onium cation photoinitiator comprises an onium cation complexed with a pseudo-metal anion (X ⁻ ), preferably a polyarylonium cation. A preferred pseudometal anion is a perfluorometalate anion. Suitable pseudometal anions (X ⁻ ) are known in the art. Non-limiting examples of suitable and preferred pseudometal anions include BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , and B (C ₆ F ₅ ) ₄ ⁻ .

  The cationic photoinitiators of the present invention can also include organometallic compounds such as iron arene salts, zirconocene salts, manganese decacarbonyl salts. Suitable organometallic compounds are disclosed in Koleske, JV, Radiation Curing of Coatings, ASTM Manual 45 (2002).

  Michael addition is catalyzed by strong bases such as diazabicycloundecene (DBU). Following the Michael reaction, the base is preferably reacted and neutralized by the addition of an acidifying agent. Suitable acidifying agents include, but are not limited to, phosphoric acids, carboxylic acids, acid half esters, and inorganic acid esters (eg, hydroxyethyl methacrylate phosphate or hydroxyethyl acrylate phosphate). Preferably, the acidifying agent is added in at least a stoichiometric amount with respect to the base. However, the acidifying agent can also be added in superstoichiometric amounts, which may cause storage stability problems.

  Prior to curing, in the absence of any basic species that can catalyze crosslinking (eg amines, alkoxides, phenoxides, etc.), the reactants are mixed at any time to form a stable and homogeneous mixture. be able to. Storage stability, defined quantitatively as no premature gelation and minimal increase in resin viscosity, ensures that the system is fully acidified and the mixture is not exposed to actinic light. Can be achieved on the condition that There is no established “standard” in this regard. Acceptability criteria are defined by the end user.

  Epoxides suitable for the purposes of the present invention can be selected by those skilled in the art from a wide range of commercially available epoxides. The choice of epoxide is dictated by the properties that the final cured product is desired to have. In order to cause crosslinking, the epoxide must be at least difunctional. A preferred bifunctional epoxide is bis- (3,4-epoxycyclohexyl) adipate. A more preferred bifunctional epoxide is 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate. Compounds having more than two epoxy functionalities are also suitable for the purposes of the present invention.

  Epoxides suitable for the present invention have a Brookfield viscosity of less than about 1000 cP at 25 ° C. Suitable epoxides provide strong adhesion to the metal when cured. One of ordinary skill in the art can readily determine an appropriate value for adhesion by ASTM D3359, which is known in the art, among other methods. Suitable epoxides are clear, single phase liquids at standard temperature and pressure. Furthermore, suitable epoxides are stable as defined by the minimal tendency to separate from or react with the mixed Michael oligomers.

  The properties of the final composition can be altered appropriately by including a “modifying epoxide”. Epoxides suitable as modifiers include limonene monoxide, diglycidyl ether of bisphenol A, and epoxyphenol novolac. The last two cited epoxides are not considered alicyclic epoxides. However, they are suitable for the purposes of the present invention.

  UV photopolymerization is demonstrated by applying a portion of the composition of the present invention to the surface. Spread the composition on the surface to a thickness of about 3 mils or less. The resin is applied to an aluminum or stainless steel substrate by the “stretch” method. The specimens were cured with a Fusion Systems UV curing unit using a 600 Watt H bulb and a belt speed of 40 feet / minute.

  The coating performance characteristics are measured by various test methods well known to those skilled in the art. Hardness and chemical resistance were evaluated on an aluminum panel, adhesion was evaluated on a steel panel, and wear resistance was measured on a white painted aluminum panel.

  hardness. Film hardness is the ability of a coating to resist cutting, shearing, or penetration by a hard object. The method for measuring coating hardness is to scratch the film with a pencil core of known hardness. This result is reported as the hardest core that does not scratch or cut the film to reach the substrate. Although this test is very subjective, it provides a quick and fairly reliable method for determining film hardness. As measured by the pencil method: soft <6B-5B-4B-3B-2B-B-HB-F-H-2H-3H-4H-5H-6H> hard. This method complies with the method of ASTM D3363.

  Solvent resistance. Solvent resistance is the ability of a coating to resist solvent attack or film deformation. Rubbing the coating with a cloth sufficiently soaked with a suitable solvent (rubbing) is one way to assess whether a specific level of solvent resistance has been achieved. All rubbing tests were performed with methyl ethyl ketone (MEK) and used a double rub method, which was a single full back and forth movement on the coated surface. To standardize the test operation, a cheesecloth was secured to the round end of a 16 ounce round head hammer. Since the measurer holds the hammer at the base of the handle, this double rub method utilizes the hammer weight. This test was conducted until the double rubbing action cut into the film or a noticeable film malfunction was evident. This test is a variation from the method of ASTM D4752.

  Gloss (gloss). Measured using a gloss meter. This method complies with the method of ASTM D523.

  Abrasion resistance. Measurements were made using Atlas Crockmeter® and 0000 steel wool. The test method used is in accordance with ASTM D6279, using a black colored panel as a substrate and measuring 20 ° gloss before and after wear, or a variation of ASTM 6279 using a white colored substrate panel And by measuring the 60 ° gloss. Abrasion resistance is reported by% gloss retention, defined as (Gloss of worn coating / Gloss of non-weared coating) X 100.

  Adhesion was performed using phosphorylated steel Q-panels (R) as a test coating substrate (Q-panels (R) is a trademark of Q-Panel Lab Products, Cleveland, Ohio) Is). The adhesion test was performed by a cross-hatch method on a rigid substrate, using a Gardco Blade PA-2054 (11 teeth, 1.5 mm cutter), and using the ASTM D3359 deformation method by test tape method B. The test tape used was Permacel # 99. This ASTM test is reported with values from 0B to 5B, where 0B is fully peeled and 5B is characterized by excellent adhesion.

[Example 1]
New Michael addition polyacrylate resins based on the Michael donors ethyl acetoacetate and 2,4-pentanedione (2,4-PD) are described in US Pat. Nos. 5,945,489 and 6,025, It was synthesized according to the specification of No. 410. The Michael polyacrylate resin was mixed with various alicyclic epoxides at various levels. The resin / epoxide composition was then applied to a phosphorylated steel substrate and cured with a UV dose of 1500 mJ / cm ² . All tests were performed on cured resin coatings 24 hours after UV irradiation to ensure that the so-called “dark cure” of the subsequent epoxy composition was complete. Results are reported together in Tables I, II, and III.

  In Table I, Michael addition polyacrylate resin A comprises hexanediol diacrylate (HDDA) and tris reacted with ethyl acetoacetate such that the total acceptor and donor are in the ratio of 2.2: 1 moles. A 75/25 molar mixture of methylolpropane triacrylate (TMPTA) and further neutralized with Ebecryl 168 (hydroxyethyl methacrylate phosphate). The epoxy compounds are CYRACURE (registered trademark) UVR-6150 and CYRACURE (registered trademark) UVR-6128 (Union Carbide), respectively, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bis- (3 , 4-epoxycyclohexylmethyl) adipate. The photoinitiator used was CD-1010® (Sartomer), a mixture (50%) of triarylsulfonium hexafluoroantimonate salts in propylene carbonate. The leveling agent used was Fluorad® FC4430 (3M).

  Michael addition polyacrylate resin B in Table II is a 94.4 / 5.6 molar mixture of HDDA and Laromer PE 55F (BASF) (polyester acrylate having a molecular weight of about 1000) with 2,4-pentanedione, The reaction was carried out at a molar ratio of 2.2: 1 and neutralized with Ebecryl 168.

  Michael addition polyacrylate resin C in Table III was obtained by reacting dipropylene glycol diacrylate with ethyl acetoacetate in a molar ratio of 2.2: 1 and neutralizing with Ebecryl 168.

  The results in Tables I, II, and III show that the performance benefits of the UV addition cured coating of Michael addition polyacrylate resin and the performance benefits of the UV radiation cured coating of the epoxy compound are combined by combining the two together. It shows that you can get.

[Example 2]
Michael addition polyacrylate resins based on HDDA and TMPTA (75:25 ratio) and ethyl acetoacetate are prepared according to the methods described in US Pat. Nos. 5,945,489 and 6,025,410. Synthesized. This resin was mixed with Uvacure® 1562 (UCB Chemicals), an acrylate-alicyclic epoxide blend having both acrylate and epoxy functionality. This mixture was then applied to a phosphorylated steel or aluminum substrate and cured with a UV dose of 1500 mJ / cm ² . Adhesion, solvent resistance, pencil hardness, gloss, and wear resistance are as shown in the previous examples. As described in Example 1, all tests were performed 24 hours after UV irradiation.

The use of a binary cure or “hybrid cure” coating system is similar to the use of standard coatings, for example for substrate protection and / or modification. However, the usefulness of the dual curing capability allows the development of the best film properties with greater freedom than conventional coating techniques. For example, full cure (characterized by film hardness and solvent resistance) is only about 500 mJ / cm ² UV irradiation (or less) compared to 30 minutes of high temperature “baking” for alkyd or melamine based coatings. Can be achieved in seconds. In direct contrast to conventional UV-based coatings, the present Michael polyacrylate resin / epoxide binary curing system is capable of “initial strength (green strength)” or with very small UV pulses or small amounts of amine or peroxide catalysts. "Blocking resistance" can be expressed. Once the first stage or initial extent of curing has been reached, the coating can then be handled by molding, printing, or laminating operations before achieving full curing. Once fully cured, many coatings are even more difficult to bend and mold and / or they do not adhere during the molding operation. Thus, the possibility of binary curing allows handling of the substrate in a way that conventional systems, including conventional UV curable coatings, cannot mimic.

Monoacrylate can be used to soften the resin properties when needed. For example, the addition of 25 mol% or less of a monofunctional acrylate (eg, isobornyl acrylate, IBOA) allows the coating to be “toughened” without increasing brittleness due to more crosslinking. Other monofunctional monomers, such as 2- (2-ethoxyethoxyethyl) acrylate (EOEOEAA) or dodecyl acrylate, to reduce film adhesion to the substrate or to coating pigments, nanoparticles, waxes, or silicones Can be added to enhance incorporation into the formulation. Suitable monoacrylate, simple _C 1 _{-C 18} acrylates esters, isobornyl acrylate (IBOA), tetrahydrofurfuryl acrylate (THFFA), 2- (2- ethoxyethoxy) ethyl acrylate (EOEOEA), phenoxyethyl Acrylate (PEA), hydroxyalkyl acrylate, monoalkyl polyalkylene glycol acrylate, siloxane acrylate, silane acrylate, silicone acrylate, perfluoroalkyl acrylate, caprolactone acrylate, and mixtures thereof include, but are not limited to.

  All publications, patents, patent application publications, and ASTM test methods cited herein are specifically and individually incorporated by reference for each individual publication, patent, patent application publication, and ASTM test method. In particular, any and practically incorporated herein. In case of conflict, the present disclosure will prevail. In particular, copending applications (not numbered yet; Attorney Docket Number 20435/141; 20435/144; 20435/146; 20435/147; and 20435/148) are hereby incorporated by reference in practice.

FIG. 1 is a synthesis scheme of a crosslinked Michael polyacrylate gel. FIG. 2 is a scheme for the synthesis of UV curable oligomers by Michael addition reaction of trimethylolpropane triacrylate (TMPTA) and ethyl acetoacetate (EAA).

Claims (53)

A liquid oligomer composition comprising: an alicyclic epoxide; and an organic soluble, non-gelled, uncrosslinked Michael addition polyacrylate reaction product.   The liquid oligomer composition of claim 1, wherein the Michael addition polyacrylate product is formed from a multifunctional acrylate Michael acceptor and a β-dicarbonyl Michael donor.   The liquid oligomer composition of claim 1, wherein the β-dicarbonyl Michael donor is selected from the group consisting of β-ketoesters, β-diketones, β-ketoamides, β-ketoanilides, and mixtures thereof.   The liquid oligomer composition of claim 1, wherein the multifunctional acrylate Michael acceptor is selected from the group consisting of diacrylates, triacrylates, and tetraacrylates.   The liquid oligomer composition according to claim 1, wherein the β-dicarbonyl Michael donor is a β-diketone or a β-ketoester.   The liquid oligomer composition according to claim 3, wherein the β-dicarbonyl has an equivalent functionality (N) (N = 2, 4, 6 or 8). The molar ratio of the acrylic functionality of the diacrylate Michael acceptor to the β-dicarbonyl donor is:
When the β-dicarbonyl functionality = 2, ≧ 1: 1;
If the β-dicarbonyl functionality = 4, ≧ 4.5: 1,
≧ 4.5: 1 when the β-dicarbonyl functionality = 6, and ≧ 3.5: 1 when the β-dicarbonyl functionality = 8
The liquid oligomer composition according to claim 4, wherein The molar ratio of the acrylic functionality of the triacrylate Michael acceptor to the β-dicarbonyl donor is:
If the β-dicarbonyl functionality = 2, ≧ 2.25,
If the β-dicarbonyl functionality = 4, ≧ 6.4: 1,
When the β-dicarbonyl functionality = 6, ≧ 7.8: 1, and when the β-dicarbonyl functionality = 8, ≧ 7.4: 1
The liquid oligomer composition according to claim 4, wherein The molar ratio of acrylic functionality of the tetraacrylate Michael acceptor to the β-dicarbonyl donor is:
If the acetoacetate functionality = 2, ≧ 6.6,
When the β-dicarbonyl functionality = 4, ≧ 12.3: 1,
≧ 13.2: 1 when the β-dicarbonyl functionality = 6 and ≧ 12.7: 1 when the β-dicarbonyl functionality = 8
The liquid oligomer composition according to claim 4, wherein   The liquid oligomer composition of claim 1, wherein the alicyclic epoxide has a Brookfield viscosity of less than 1,000 cP at 25 ° C.   11. The liquid according to claim 10, wherein the alicyclic epoxide is selected from the group consisting of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bis- (3,4-epoxycyclohexyl) adipate. Oligomer composition.   The liquid oligomer composition according to claim 1, further comprising a modifying epoxide.   The liquid oligomer composition according to claim 12, wherein the modifying epoxide is selected from the group consisting of limonene monoxide, bisphenol A diglycidyl ether, and epoxyphenol novolac.   The liquid oligomer composition according to claim 11, wherein a preferred alicyclic epoxide is 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate.   The liquid oligomer composition according to claim 1, wherein the Michael addition reaction is performed in the presence of a strong base.   The base was generated in situ by cyclic amidines, guanidines, Group I alkoxides, quaternary hydroxides, quaternary alkoxides, and reactions between halide anions and epoxy groups. 14. The liquid oligomer composition according to claim 13, selected from the group consisting of alkoxide bases.   The liquid oligomer composition according to claim 14, wherein the base is selected from the group consisting of diazabicycloundecene (DBU), diazabicyclo-nonene (DBN), and 1,1,3,3-tetramethylguanidine. .   15. The liquid oligomer composition according to claim 14, wherein the alkoxide is generated in situ by a reaction between a quaternary halide and an epoxide group. The diacrylate is
Ethylene glycol diacrylate, propylene glycol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, tetrapropylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene Glycol diacrylate, ethoxylated bisphenol A diacrylate, bisphenol A diglycidyl ether diacrylate, resorcinol diglycidyl ether diacrylate, 1,3-propanediol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol Diacrylate, 1,6-hexanedio Diacrylate, neopentyl glycol diacrylate, cyclohexane dimethanol diacrylate, ethoxylated neopentyl glycol diacrylate, propoxylated neopentyl glycol diacrylate, ethoxylated cyclohexane dimethanol diacrylate, propoxylated cyclohexane dimethanol diacrylate, acrylic The liquid oligomer composition according to claim 4, wherein the liquid oligomer composition is selected from the group consisting of fluorinated epoxy diacrylates, aryl urethane diacrylates, aliphatic urethane diacrylates, polyester diacrylates, and mixtures thereof. The triacrylate is
Trimethylolpropane triacrylate, glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol tri Claims selected from the group consisting of acrylates, pentaerythritol triacrylates, aryl urethane triacrylates, aliphatic urethane triacrylates, melamine triacrylates, aliphatic epoxy triacrylates, epoxy novolac triacrylates, polyester triacrylates, and mixtures thereof. Item 5. The liquid oligomer composition according to Item 4. The tetraacrylate is
Di-trimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, ethoxylated dipentaerythritol tetraacrylate, propoxylated dipentaerythritol tetraacrylate 5. The liquid oligomer composition of claim 4, selected from aryl urethane tetraacrylate, aliphatic urethane tetraacrylate, polyester tetraacrylate, melamine tetraacrylate, epoxy novolac tetraacrylate, and mixtures thereof. The β-dicarbonyl donor compound having functionality = 2 is
Ethyl acetoacetate, methyl acetoacetate, 2-ethylhexyl acetoacetate, lauryl acetoacetate, t-butyl acetoacetate, acetoacetanilide, N-alkylacetoacetanilide, acetoacetamide, 2-acetoacetoxyethyl methacrylate, allyl acetoacetate, benzyl Acetoacetate, 2,4-pentanedione, isobutyl acetoacetate, and 2-methoxyethyl acetoacetate,
The liquid oligomer composition according to claim 6, which is selected from the group consisting of: The β-dicarbonyl donor compound having functionality = 4 is
Selected from the group consisting of 1,4-butanediol diacetoacetate, 1,6-hexanediol diacetoacetate, neopentyl glycol diacetoacetate, cyclohexanedimethanol diacetoacetate, and alkoxylated bisphenol A diacetoacetate, The liquid oligomer composition according to claim 6. The β-dicarbonyl donor compound having functionality = 6 is
The liquid oligomer composition according to claim 6, selected from the group consisting of trimethylolpropane triacetoacetate, glycerin triacetoacetate, polycaprolactone triacetoacetate, and alkoxylated derivatives thereof.   The liquid oligomer composition according to claim 6, wherein the β-dicarbonyl donor compound having functionality = 8 is pentaerythritol tetraacetoacetate and alkoxylated derivatives thereof.   The liquid oligomer composition of claim 2, wherein the Michael addition reaction occurs in the presence of at least one non-reactive solvent. The non-reactive solvent is styrene, t-butyl styrene, α-methyl styrene, vinyl toluene, vinyl acetate, allyl acetate, allyl methacrylate, diallyl phthalate, C ₁ -C ₁₈ -methacrylic acid ester, dimethacrylate, and The liquid oligomer composition according to claim 24, selected from the group consisting of trimethacrylate.   The liquid oligomer composition of claim 1, wherein the composition is shelf stable for more than 1 month and has residual pendant unsaturated acrylate groups.   The liquid oligomer composition according to claim 2, further comprising an acidifying agent.   30. The liquid oligomer composition according to claim 29, wherein the acidifying agent is selected from the group consisting of phosphoric acids, carboxylic acids, acid half esters, and inorganic acid esters.   Preferred acidifying agents are 2-hydroxyethyl acrylate phosphate ester, 2-hydroxyethyl methacrylate phosphate ester, 2-hydroxypropyl acrylate phosphate ester, 2-hydroxypropyl methacrylate phosphate ester, 4-hydroxybutyl 31. The liquid oligomer composition according to claim 30, wherein the liquid oligomer composition is selected from the group consisting of a phosphate ester of acrylate and a phosphate ester of 4-hydroxybutyl methacrylate.   The liquid oligomer composition according to claim 2, further comprising a monoacrylate. The monoacrylate is a simple _C 1 _{-C 18} acrylate ester, isobornyl acrylate (IBOA), tetrahydrofurfuryl acrylate (THFFA), 2- (2- ethoxyethoxy) ethyl acrylate (EOEOEA), phenoxyethyl acrylate (PEA ), A hydroxyalkyl acrylate, a monoalkyl polyalkylene glycol acrylate, a siloxane acrylate, a silane acrylate or silicone acrylate, a perfluoroalkyl acrylate, a caprolactone acrylate, and mixtures thereof. Composition.   33. The liquid oligomer composition of claim 32, wherein the monoacrylate is present from about 0 to about 50 mol%.   35. The liquid oligomer composition of claim 32, wherein the monoacrylate is present from about 0 to about 25 mole percent.   34. The liquid oligomer composition of claim 32, wherein the monoacrylate is present from about 0 to about 12.5 mol%.   The liquid oligomer composition according to claim 2, further comprising a free radical generator.   The liquid oligomer composition according to claim 37, wherein the free radical generator contains a peroxide. 38. The liquid oligomer of claim 37, wherein the peroxide is selected from the group consisting of benzoyl peroxide, methyl ethyl ketone peroxide (MEKP), tert-butyl perbenzoate (TBPB), cumyl peroxide, and t-butyl peroxide. Composition.
The liquid oligomer composition according to claim 2, further comprising a cationic photoinitiator.   40. The liquid oligomer composition of claim 39, wherein the cationic photoinitiator is selected from the group consisting of perfluorometalate onium salts, iron arene salts, zirconocene salts, and manganese decacarbonyl salts. The perfluoro metalate ^{_{is, BF 4 -, PF 6 -}} , SbF 6 -, and _{B (C 6 F 5) 4} - is an anion chosen from the group consisting of liquid oligomeric composition as claimed in claim 39 .   40. The liquid oligomer composition according to claim 39, wherein the onium is a cation selected from the group consisting of arylsulfonium cations, aryliodonium cations, and arylphosphonium cations.   The liquid oligomer composition according to claim 2, wherein the composition further comprises at least one additive.   The additive is selected from the group consisting of pigments, gloss modifiers, fluidizers and leveling agents, and other additives suitable for formulating coatings, paints, laminates, sealants, adhesives, and inks. 44. The liquid oligomer composition according to claim 43. Alicyclic epoxides;
A polymerization product cured from a liquid oligomer composition comprising a cationic photoinitiator; and an organic soluble, non-gelled, uncrosslinked Michael addition acrylate reaction product.   44. The polymerization product cured from the liquid oligomer composition of claim 43, further comprising a free radical generator.   45. The polymerization product according to claim 44, wherein the free radical generator is light having a chemical action.   46. The polymerization product of claim 45, wherein the free radical generator is a peroxide.   At least one selected from the group consisting of pigments, gloss modifiers, fluidizers and leveling agents, and other additives suitable for formulating coatings, paints, laminates, sealants, adhesives, and inks 46. The polymerization product of claim 45, further comprising: A method for producing a liquid oligomer composition, wherein the oligomer composition has pendant unsaturated acrylate groups and comprises the following steps:
Reacting a polyfunctional acrylate Michael acceptor with a β-dicarbonyl Michael donor in the presence of a strong base to form a Michael adduct;
Adding an acidifying agent to the adduct in at least stoichiometric amount with respect to the base;
Mixing an alicyclic epoxide; and mixing a cationic photoinitiator;
The manufacturing method of the liquid oligomer composition containing this. A method for using a liquid oligomer composition comprising the following steps:
Providing a liquid oligomer composition comprising an alicyclic epoxide, a cationic photoinitiator, and an organic soluble, non-gelled, uncrosslinked Michael addition polyacrylate reaction product;
Applying the oligomer composition to a surface; and curing the composition;
Including methods.   The composition is selected from the group consisting of pigments, gloss modifiers, fluidizers and leveling agents, and other additives suitable for formulating coatings, paints, laminates, sealants, adhesives, and inks. 50. The method of using a liquid oligomer composition according to claim 49, further comprising at least one additive.   46. A substrate coated with the polymerization product of claim 45.

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