In this paper, referring to the experimental observation of Thomas and Pellon, the authors consider the possible features of the development of the inter- and intra-molecular forces of polymer and monomer molecules in the reaction mixture. Then, a critical chain length is proposed to be a criterion for the loci of polymerization for the polymer molecules. The polymer molecules formed initially exist and react in the solution phase. As soon as they attain a chain length longer than the critical chain length, they will separate from the solution phase, and continue their reaction in the precipitation phase by the diffusion-controlled process. The chain transfer to monomer reaction is suggested as the deactivation reaction for the precipitated polymer radicals. In the kinetic treatment, the unsteady- state condition is applied for the precipitation phase, while the steady-state assumption is used for the solution phase. Using the kinetic model proposed above, the authors provide the kinetic parameters for this acrylonitrile polymerization. The simulations of conversion-time, rate-conversion, and molecular weight- conversion obtained fit excellently with the data of Hamielec et al. The critical chain length for this acrylonitrile system is found to be a function of the reaction temperature and the conversion.
|Number of pages||10|
|Journal||Journal of the Chinese Institute of Engineers, Transactions of the Chinese Institute of Engineers,Series A/Chung-kuo Kung Ch'eng Hsuch K'an|
|Publication status||Published - 1984 Apr|
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