Entanglement transfer length

We first compute the probability p that at least one entangled chain is left unbroken in a given entanglement transfer length. Since for the assumed random chain scission the probability of a certain number of breaks follows a binomial distribution one finds... 

Fig. 26. The calculated probability that at least one entangled chain remains unbroken in each entanglement transfer length along craze fibrils of total length (total craze thickness) T as a function of x the weight fraction high M PS in the blend...

Figures 1-4 show that when polymerizations were carried out at low concentrations of initiator and/or at low temperatures, the agreement between the model predictions and the experimental data is not so good. This is due to the fact that under those reaction conditions where R is low a large kinetic chain length is expected. When this is so, chain transfer to monomer becomes a reaction to be taken into account, since it markedly influences the chain length of the polymer being formed. A decrease in the instantaneous degree of polymerization, due to chain transfer to monomer, will reduce the concentration of the entangled radicals and, consequently, a decrease in the rate of polymerization is expected.

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