화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.36, No.10, 1501-1508, 1998
Effects of complex formation and cyclization in radical copolymerization of allyl(metha)acrylates with maleic anhydride
Radical copolymerization of allyl acrylate (AA) and allyl methacrylate (AMA) as bifunctional monomers of donor (allyl)-acceptor (acryl) type with maleic anhydride (MA) as an acceptor monomer were carried out in metrhyl ethyl ketone (MEK) at 50-70 degrees C in the presence of 2,2'-azoisobutyronitrile (AIBN) as initiator. Constants of complex formation (K-c), cyclization (k(cl)), and copolymerization (r(1), r(2), r(1c), r(1c1), and r(1c2)) as well as energies of activation for cyclization (E-ac) and copolymerization reactions (E-a), and orders for the monomer (m) and initiator (n) concentrations were determined. The following values were found, for AA and AMA, respectively : K-c = 0.038 and 0.11 L/mol in deutered acetone at 35 +/- 0.1 degrees C, k(cl) = 6.45 and 6.53, r(1) = 0.083 +/- 0.005 and 0.028 +/- 0.002, r(2) = 0.027 +/- 0.002 and 0.063 +/- 0.003 (by the Kelen-Tudos method), r(1c) = 0.04 and 0.025, r(1c1) = 0.128 and 0.176, r(1c2) = 0.127 and 0.177 (by the Seiner-Litt equation), E-ac = 28.9 and 28.7 kJ/mol, E-a = 67.0 and 87.9 kJ/mol, m = 1.53 and 1.45, and n = 0.50 and 0.52. The presence of cyclic, unsaturated, and anhydride fragments in the macromolecules was confirmed with FTIR data and chemical (iodometrical and potentiometric titrations) analysis. It was established that complex formation in the monomer systems studied is the main factor for alternating cyclocopolymerization leading to formation of copolymers containing lactone and linear-unsaturated fragments in the macromolecular chain.