engleski

Copolymerization of N-Acryl-N, N’-dicyslohexylurea and N-Methacryl-N, N’-dicyclohexylurea with Styrene

N-Acryl-N, N´-dicyclohexylurea (A-DCU) homopolymers and copolymers with styrene (St) are prepared under the standard free-radical-initiated polymerization. Copolymers of A-DCU with St prepared under different monomer-to-monomer ratios in the feed, have random composition with an azeotropic point at ratio of 0.73 (A-DCU) to 0.27 (St). N-Methacryl-N, N´-dicyclohexylurea (MA-DCU) does not homopolymerize, but copolymerizes with St to randomly composed copolymers. Reactivity ratios determined by the Kelen-Tüdös method are: r1 (A-DCU) = 0.80 ; r2 (St) = 0.50, and r1 (MA-DCU) = 0.18 ; r2 (St) = 4.84. All copolymers decompose under TGA conditions by a two step mechanism. In the first step at temperature of about 200°C separates cyclohexylisocyanate (C6H11NCO) under the formation of thermally stable poly(C6H11-acrylamido-co-St) and poly(C6H11-methacrylamido-co-St) which decompose at temperature of 450°C without the residue.

Poly(acryl-dicyclohexylurea-co-styrene); Poly(methacryl-dicyclohexylurea-co-styrene); Poly(cyclohexylacrylamide); Poly(cyclohexylacrylamide-co-styrene); Poly(cyclohexylmethacrylamide-co-styrene); Reactivity Ratios; Rate of Copolymerization; Mechanism of Th

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