p-Nitrobenzyl Triphenyl Phosphonium Ylide as New Initiator in Polymerization of Ethylacrylate

Abstract

1,2-Dipolar compound containing phosphorus ylide (p-NBTPY) initiated radical polymerization of ethylacrylate in dioxane yielding syndiotactic polyethylacrylate, as evidenced by FTIR and ¹H NMR. It was investigated dilatometrically at 65 ± 0.1 ºC for 1 h under nitrogen atmosphere. The kinetic expression is R_p µ µ [I]^0.4 [M]^1.2. The system follows non-ideal kinetics because of primary radical termination. The activation energy and kp 2/kt were calculated as 53 kJ/mol and 0.15 × 10^-2 mol L^-1 s^-1, respectively. Thermal properties of polymer have been established with the help of DSC and TGA technique. The polymer has been characterized by MALDI-TOF. The absence of phosphorus in polymer matrix is confirmed from the scanning electron microscopy. The initiation is brought about by phenyl radical as evidenced from six hyperfine lines in electron spin resonance spectrum.