PYROLYSIS OF 1-METHACRYLOYL-3-PHENYLTHIOUREA AND ITS POLYMER - RATE AND MECHANISM

The rates of thermal decomposition of 1-methacryloyl-3-phenylthiourea (1a), 1-methacryloyl-3-(4-nitrophenyl)thiourea (1b), 1-methacryloyl-3 -(4-chloro phenyl)thiourea (1c), 1-methacryloyl-3-(4-methylphenyl)thio urea (1d), 1 - methacryloyl-3-(4-methoxyphenyl)thiourea (1e), poly-1-m ethacryloyl-3-phenylthiourea (2) and 1-acryloyl-3-phenylthiourea (3) h ave been measured between 390 and 465 K. The reactions were homogeneou s and unimolecular with log A = 11.48, 11.48, 11.81, 11.43, 11.11, 11. 21 and 11.87 s(-1) and E(a) = 119.7, 111.93, 120.07, 121.94, 120.84, 1 24.64 and 122.68 kJ mol(-1), respectively. Product analysis was used t o outline feasible pathways for the elimination reaction of the compou nds under study.