Self-photoinitiating water-dispersible acrylate ionomers and synthetic methods

Abstract

The invention detailed herein comprises a family of novel multifunctional acrylate ionomeric resins, which are water-dispersible, and have built-in photoinitiator. The inventive resins are made self-photoinitiating by their reaction with β-keto esters (e.g., acetoacetates), β-diketones (e.g., 2,4-pentanedione), β-keto amides (e.g., acetoacetanilide, acetoacetamide), and/or other β-dicarbonyl compounds that can participate in the Michael addition reaction as “Michael donors.” These water-dispersible resins cure under standard ultraviolet (UV) cure conditions to give tack-free coatings without the addition of traditional photoinitiators. The present invention further relates to the use of these resins in coatings.

1 . An ionomer comprising: 
 an ionic, UV-curable Michael resin,    an amount of water; and    a counter-ion wherein the ionic,    wherein the UV-curable Michael resin comprises:    at least one hydroxy-functional Michael resin and    at least one ionic isocyanate-terminated urethane oligomer    wherein said at least one hydroxy-functional Michael resin comprises a β-dicarbonyl monomer, a hydroxy-functional acrylate monomer and a multifunctional acrylate and    wherein said at least one ionic isocyanate-terminated urethane oligomer comprises an isocyanate-reactive hydrophilic monomer, a polyol and at least one multifunctional isocyanate.    
     
     
         2 . The ionomer of  claim 1 , further comprising at least one additive selected from the group consisting of pigments, gloss modifiers, flow and leveling agents and other additives as appropriate to formulate coatings, paints, laminates, sealants, adhesives, foundry sand binders, and inks.  
     
     
         3 . A polymerized product comprising the ionomer according to  claim 1 , cured with a free radical generator.  
     
     
         4 . The polymerized product, according to  claim 3 , wherein said free-radical generator is actinic light.  
     
     
         5 . The polymerized product, according to  claim 3 , wherein said free-radical generator is electron beam radiation.  
     
     
         6 . The polymerized product, according to  claim 3 , wherein said free-radical generator is a peroxide.  
     
     
         7 . The polymerized product, according to  claim 6 , wherein said peroxide is selected from the group consisting of methyl ethyl ketone peroxide (MEKP), tert-butyl perbenzoate (TBPB), cumyl peroxide, and t-butyl peroxide.  
     
     
         8 . The polymerized product, according to  claim 3 , further comprising at least one additive selected from the group consisting of pigments, gloss modifiers, flow and leveling agents and other additives as appropriate to formulate coatings, paints, laminates, sealants, adhesives, foundry sand binders, and inks.  
     
     
         9 . A method of utilizing an ionic Michael resin comprising: 
 providing a substrate;    applying the ionomer of  claim 1  to said substrate; and    curing said resin.    
     
     
         10 . The method of using an ionic Michael resin, according to  claim 9 , wherein applying comprises a coating method selected from the group consisting of roll-coating, spray-coating, brush-coating, dip-coating, and electrocoating.  
     
     
         11 . A method of fabricating a backbone-ionic, UV-curable ionomer comprising: 
 providing a resin reactor having a dry atmosphere;    providing a polyol to said reactor;    providing an isocyanate-reactive, hydrophilic monomer to said reactor;    providing a urethanation catalyst to said reactor;    providing a polyisocyanate to said reactor;    maintaining a reaction mixture at a reaction-effective temperature; and    providing a hydroxy-functional, multifunctional acrylate Michael oligomer.    
     
     
         12 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 11 , wherein a preferred isocyanate-reactive, hydrophilic monomer is dimethylolpropionic acid.  
     
     
         13 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 11 , wherein said urethanation catalyst is selected from the group consisting of dibutyltin dilaurate, tin(II) octoate, and diazabicyclo[2.2.2]octane.  
     
     
         14 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 11 , wherein providing a hydroxy-functional, multifunctional acrylate d Michael oligomer comprises: 
 providing a resin reactor;    providing a polyol multifunctional acrylate monomer to said reactor;    providing a hydroxyacrylate monomer to said reactor;    providing a β-dicarbonyl monomer to said reactor; and    providing a Michael addition catalyst.    
     
     
         15 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 14 , wherein said Michael addition catalyst is a strong base that is readily soluble in the monomer mixtures.  
     
     
         16 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 14 , wherein said Michael addition catalyst is selected from the group consisting of diazabicycloundecene, diazabicyclononene, 1,1,3,3-tetramethyl guanidine, Group I alkoxide bases, quaternary hydroxides and alkoxides, and organophilic alkoxide bases generated in situ from the reaction between a halide anion and an epoxide moiety.  
     
     
         17 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 11 , further comprising: 
 adding an amount of water; and optionally    adding a counter-ion.    
     
     
         18 . The method of fabricating a backbone-ionic, UV-curable ionomer, according to  claim 17 , further comprising adding at least one additive selected from the group consisting of pigments, gloss modifiers, flow and leveling agents and other additives as appropriate to formulate coatings, paints, laminates, sealants, adhesives, foundry sand binders, and inks.  
     
     
         19 . A method of fabricating a pendant-ionic, UV-curable ionomer comprising: 
 providing a resin reactor having a dry atmosphere;    providing a β-dicarbonyl;    providing a multifunctional acrylate;    providing a Michael addition catalyst; and    maintaining a reaction-effective temperature.    
     
     
         20 . The method of fabricating a pendant-ionic, UV-curable ionomer, according to  claim 19  further comprising: 
 adding an amount of water; and optionally    adding a counter-ion.    
     
     
         21 . The method of fabricating a pendant-ionic, UV-curable ionomer, according to  claim 19  further comprising adding at least one additive selected from the group consisting of pigments, gloss modifiers, flow and leveling agents and other additives as appropriate to formulate coatings, paints, laminates, sealants, adhesives, foundry sand binders, and inks.  
     
     
         22 . An oligomerized pendant-ionic, multifunctional acrylate Michael resin comprising: 
 at least two equivalents of a pendant-ionic multifunctional acrylate Michael resin; and    a primary amine, wherein said amine is disubstituted with said resin.