ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Anionic polymerisations of ethyl and butyl cyanoacrylates (ECA and BCA) in THF, initiated by benzyldimethylamine (BDMA), triethylamine (TEA) and tribenzylamine (TBA) were studied between 50 and -78°C. Initiator utilisation was very low, and polymer molecular weights correspondingly high, though believed to be depressed by acid impurities in the monomer samples. Conversion curves reached internal 1st order kinetics, almost instantaneously when the initiator was BDMA, more slowly with TEA, and only after a long acceleration period with TBA, which gave overall rates some two orders of magnitude lower than those induced by the other amines. With BCA initiated by BDMA or TEA, the rate constants increased as reaction temperature was lowered. A general kinetic scheme is suggested, postulating no intrinsic termination reactions, and complex initiation processes, which according to the nature of amine and monomer may involve either one or two pre-initiation equilibria.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1981.021820213
Permalink