Unperturbed dimensions of polymers revisited through the blob theory: the viscometric expansion factor

作者：Dondos Anastasios^*

来源：E-Polymers, 2013, 13(1): 014.

Plotting log([eta]/M-1/2) versus log(N/N-c) where [eta] is the intrinsic viscosity of the macromolecular chain of molecular mass equal to M and N/N-c is the number of blobs of which this chain consists (N: the number of statistical segment of the chain and N-c : the number of statistical segment of one blob), we obtain the unperturbed dimensions parameter of the blob, K-theta b. This graphical representation in this article is based on a modified, original equation of Han [6] based on the blob theory. The obtained value of K-theta b for a given polymer, dissolved in a good solvent, is lower than the unperturbed dimensions parameter, K-theta, obtained for the same polymer in the Flory%26apos;s theta conditions. Having K-theta b %26lt; K-theta we obtain for the viscometric expansion factors of a polymer, based on K-theta b or K-theta, alpha(eta b) %26gt; alpha(eta). With the obtained values of alpha(eta b) we find alpha(3)(eta b)/alpha(2)(s)alpha(H) approximate to 1, as predicted by Weill and des Cloizeauz [1], where using alpha(eta) we obtain alpha(3)(eta)/alpha(2)(s)alpha(H) approximate to 0.85 (alpha(s) and alpha(H) are the static and dynamical expansions factors).

• 出版日期2013-5-19