摘要:

A procedure for determining the ceiling temperature in radical polymerization was proposed. By means of this procedure, the ceiling temperature in radical polymerization of 2, 6-dimethyl-phenyl methacrylate was determined. It was noted that the introduction of the methyl groups in the 2- and 6-positions of phenyl methacrylate lowered remarkably the ceiling temperature as the results of steric hindrance. This polymer was consistently found to undergo easily thermal decomposition into the monomer. These results were explained by increased steric requirement between α-, 2-, and 6-methyl groups in the polymer.

ISSN:0022-233X    

DOI:10.1080/00222338108066450

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The binary systems of N-acyloxyimides with p-toluenesulfonic acid (PTS) were found to serve as effective initiators for the radical polymerization of such vinyl monomers as methyl methacrylate (MMA), methyl acrylate, and acrylonitrile. N-Benzoyloxysuccinimide (NBS), N-acetoxysuccinimide, and N-benzoyloxyphthalimide were used as the N-acyloxyimides. The polymerization of MMA with the NBS/PTS system depended upon the solvents used. The results of copolymerization of MMA with styrene initiated by this system and of the application of the spin trapping technique indicated that polymerization proceeded through a radical mechanism. A kinetic study on the polymerization of MMA with this system in ethanol was also investigated. The observed overall activation energy was 18.2 kcal/mole. The rate of polymerization (Rp) was expressed as Rp= k[NBS]0.2[PTS]0.5[MMA]1.0. From the results obtained, the initiation mechanism of vinyl polymerization by the NBS/PTS system was proposed and discussed.

ISSN:0022-233X    

DOI:10.1080/00222338108066451

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0022-233X    

DOI:10.1080/00222338108066439

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor