ISSN:
0449-296X
Schlagwort(e):
Physics
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
In the cationic polymerization of 3,3-bis(chloromethyl)oxetane induced by BF3 the solvent polarity (toluene, methylene chloride, ethylene chloride, nitrobenzene, and nitromethane) does not influence the ktr/kp ratio, where ktr stands for the rate constant of chain transfer to polymer. Increase of the overall polymerization rate is due mainly to the increase of ki. The application of the steady-state conditions in which the slow formation of the active centers is compensated by the unimolecular chain transfer to polymer allowed the determination of ktr/kp ratios for several chain-transfer agents of low molecular weight. Alcohols and ethers of different basicities were used. It was established that the ktr/kp ratio is a linear function of -pKa of the chain-transfer agents.
Zusätzliches Material:
6 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pol.1970.150080914
Permalink
