Patent ID: 6592990
Filing Date: 2003-07-15
Classification: B01J,C08F,C08L,C09J,Y10T

Abstract:
A microencapsulated adhesive composition wherein an adhesive is formed in situ in microcapsules, the microencapsulated adhesive composition comprising:a substantially water insoluble adhesive-forming core material, said core material comprising at least a first addition polymerizable pre-polymer material whose homopolymer has a Tg of less than about 0Â° C., a flash point of at least 75Â° C., and a boiling point of at least 175Â° C. at one atmosphere, and including in addition a second substantially water insoluble polymerizable pre-polymer which is multi-functional having at least two addition at least two addition polymerizable sites, selected from the group consisting of allyl methacrylate, alkene glycol dimethacrylate, alkyl dimethacrylate, alkyldiol dimethacrylate, alkoxy alkanol diacrylate, trialkanol triacrylate, alkoxy (alkoxy)n alkyl triacrylate, alkoxy (alkoxy) alkyl dimethacrylate, aralkyl dimethacrylate, cycloalkyl dimethacrylate, alkoxy dimethacrylate, bicycloalkyl dimethacrylate, cycloalkoxy dimethacrylate, allyl acrylate, alkene glycol diacrylate, alkyl diacrylate, alkyldiol diacrylate, alkoxy alkanol dimethacrylate, trialkanol trimethacrylate, alkoxy (alkoxy)n alkyl trimethacrylate, alkoxy (alkoxy)n alkyl diacrylate, aralkyl diacrylate, cycloalkyl diacrylate, alkoxy diacrylate, bicycloalkyl diacrylate, and cycloalkoxy diacrylate; wherein the alkyl moieties are of 1 to 16 carbons;wherein the cycloalkyl moieties are of 4 to 8 carbons; and wherein n is an integer from 1 to 6; and,a catalytically effective amount of a substantially water insoluble free radical initiator, said free radical initiator having a half-life of at least 1 hour at 25Â° C., said free radical initiator being soluble in the polymerizable pre-polymer material and solvent, microcapsules obtained by providing an aqueous mixture containing a colloidal dispersion of wall-forming material for forming microcapsules, wherein high shear agitation is applied to the aqueous mixture to achieve a particle size of the core material of less than about 250 &mgr;, wherein stirring at a first temperature effects microcapsule wall formation of the microcapsule wall-forming material, and wherein heating to a second temperature polymerizes the pre-polymer of the core material to form an adhesive in situ in the formed microcapsules.