Reference

Initiator efficiency of some unsymmetrical azo compounds for radical polymerization

Initiator efficiency of some unsymmetrical azo compounds for radical polymerization. Kodaira, Kazuo; Ito, Toshikuni; Omi, Makoto; Onishi, Yasushi; Ito, Katsukiyo (Aichi Inst. Technol.In this study， 30998-06-2 and 88967-58-2 are also used., Nagoya 464, Japan). Nagoya Kogyo Gijutsu Shikensho Hokoku, 31(6/7), 186-9 (Japanese) 1982. CODEN: NKGSAR. ISSN: 0027-7614. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Polystyrene [9003-53-6], poly(2,2,2-trifluoroethyl methacrylate) [54802-79-8], and poly(1H,1H,5H-perfluoropentyl methacrylate) [30998-06-2] were prepd. at 50-80° by radical polymn. with azo compd. initiators. Isopropylazodiphenylmethane (I) [88967-58-2], cyclohexylazodiphenylmethane (II) [81965-46-0], benzylazodiphenylmethane (III) [81965-47-1], and 1-phenylethylazodiphenylmethane (IV) [81051-17-4] initiators were used. For various monomers the initiator efficiency of I, II, and III was small (0.1-0.22) and that of IV at 50-60° was ~0.5, which was a similar value to that of the conventional initiator, e.g. AIBN. The chain transfer consts. of these azo initiators to radical were ~0.01-0.1, increasing in the order I = II

Some aspects of initiation and molecular weight distribution in the anionic polymerization of styrene

Some aspects of initiation and molecular weight distribution in the anionic polymerization of styrene. Ceausescu, E.; Bordeianu, R.; Cerchez, I. 100-42-5 and 9003-53-6 are also occured in this study.; Buzdugan, E.; Balanescu, M.; Ghioca, P.; Ilie, V. (Chem. Res. Inst., ICECHIM, Bucharest 77208, Rom.). Acta Polym., 34(11-12), 683-9 (English) 1983. CODEN: ACPODY. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) The rate of polymn. of styrene (I) [100-42-5] in PhMe with BuLi [109-72-8] as catalyst was first order and the activation energy was 26.3 kJ mol-1. Kinetic transitions attributed to the formation of intermediate complexes from the reacted and unreacted BuLi with I were obsd. The mol. wt. distribution of polystyrene [9003-53-6] narrowed with increasing reaction temp., indicating the activation energy of the initiation step was higher than that of the propagation step. .