SYNTHESIS AND POLYMERIZATION OF N-ACRYL-DICYCLOHEXYLUREA AND N-METHACRYL-DICYCLOHEXYLUREA AND COPOLYMERIZATION WITH α-METHYLSTYRENE

The title compounds have been prepared by the addition of acrylic acid and methacrylic acid to dicyclohexylcarbodiimide (DCC). N-Acryl-N,N′-dicyclohexylurea (Acryl-DCU) homo-polymerizes and copolymerizes with α-methylstyrene (αMeSt), while Methacryl-DCU does not polymerize under the standard free-radical-initiated polymerization. Copolymers of Acryl-DCU with αMeSt prepared under different monomer-to-monomer ratios in the feed have random composition with an azeotropic point at ratio of 0.75 (Acryl-DCU) to 0.25 (αMeSt). Reactivity ratios determined by the Kelen-Tüdös method are r 1 (Acryl-DCU) = 0.72 and r 2 (αMeSt) = 0.07. Poly(Acryl-DCU) and copolymers with αMeSt decompose under the TGA conditions by a two step mechanism. In the first step between 180 and 250°C, cyclohexylisocyanate separates by degradation of dicyclohexylurea in the side chain, while the thermally stable residue represents the poly(cyclohexylacrylamide) and copolymers with αMeSt.