956556-A is referenced by 2 patents.
Graft or block polymeric materials are made by forming a homogeneous solution of a polymerizable olefinic monomer and a resin having a molecular weight of less than 20,000 and which can be thermoset, and thereafter effecting a free-radical initiated copolymerization of the resin and monomer, and then curing the product. Resins specified are epoxy resins, polyesters, phenol-aldehyde resins, amine-aldehyde resins, coumarone-aldehyde resins, shellac, ester gums, rosin, copal, furfuraldehyde resins, polyethylene glycols, polypropylene glycols, epoxidized oils and polyvinyl acetals.; Monomers specified are acrylic and methacrylic acids and salts, alkyl esters, amides and nitriles thereof, vinyl acetate and caproate, vinyl and vinylidene chlorides bromides and fluorides, N-vinyl pyrrolidone, vinyl pyridines, alkyl vinyl and alkyl isopropenyl ketones, styrene, divinyl benzene and ethylene dimethacrylate. The resin/monomer mixture may contain a co-solvent and may be polymerized in bulk, solution or suspension in the presence of an initiator e.g. benzoyl peroxide.; The examples describe polymerizing a mixture of (1) shellac and methyl methacrylate and curing the product by heating; (2) phenol-formaldehyde resin and methyl methacrylate and curing the product in the presence of hexamethylene tetramine; (3) as in (1) but using wood rosin in place of shellac; (4) an epoxy resin and styrene and curing the product in the presence of hexahydrophthalic anhydride; (6) an epoxy resin and methyl methacrylate, and curing the product in the presence of an anhydride/amine system; and (7) polyethylene oxide and methyl methacrylate and curing the product with toluene diisocyanate.