ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
In order to calculate the average molecular weight, the molecular weight distribution or the branching of low density polyethylene, the individual values of the rate constants of the different reactions involved in the free radical polymerization are required. The method of rotating sector was applied to determine the rate constants of chain propagation and chain termination in a wide range of temperatures and pressures. This first part of the work reports the influence of the pressure. It was found that the rate constant kp of the chain propagation increases with rising pressure whereas the rate constant kt of chain termination decreases. The effect of the pressure on kp can be explained in terms of the activation volume. The decrease of kt with pressure is caused by a diffusion controlled termination reaction.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1983.021840120