ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
In the first part of this series the individual rate constants of the radical polymerization of ethylene are reported in dependency of pressure at 405 K. By further measurements under 500 - 1750 bar and 400 - 470 K, using again the method of the rotating sector, the dependency of the rate constants on both pressure and temperature was determined. With increasing temperature the rate constant of chain growth kp as well as that of chain termination kt increases. With increasing pressure, kp increases, whereas kt decreases because of the diffusion controlled termination reaction. For the chain growth an activation energy of Ep = 37 kJ/mol and an activiation volume of Δvp≠ = -25,5 ml/mol was found. The activiation parameters of the chain termination are Et = 9,9 kJ/mol and Δvt≠ = 7 ml/mol. Based on these results and literature data the rate constants of different chain transfer reactions involved in the high pressure polymerization of ethylene and their dependency on temperature and pressure were evaluated.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1983.021840419
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