Synthesis of end-functionalized low molecular weight poly(butyl acrylate) and its elongation using a diisocyanate

Abstract

Bifunctionalized poly(butyl acrylate) and poly(methyl methacrylate) were synthesized by the polymerization of butyl acrylate or methyl methacrylate using an organosamarium complex, [SmMe(C 5Me 5) 2(CH 2–CH–CHCH 2)] 2, as an initiator followed by the insertion of aldehydes. The polymerization proceeds quantitatively to afford the hydroxy-end functionalized polymer ( M n>4120) with narrow molecular weight distributions ( M w/ M n<1.13). The attempted chain elongation of the resulting polymer with 4,4′-methylenebis(phenylisocyanate) has however failed, while the chain extension was realized by the reaction of poly(ϵ-caprolactone- co-butyl acrylate- co-ϵ-caprolactone) ( M n>15,200, M w/ M n<1.23) with a diisocyanate affording the desired high solid paint with M n of 87,600 using a limited amount of THF as a solvent.