Note on the Relationship between Intrinsic Viscosity and Temperature

The Kawai-Ueyama treatment concerning the intrinsic viscosity [η] vs. temperature relationshipis extended to various cases based on the Flory-Fox (F-F), Kurata-Yamakawa (K-Y), andKurata-Stockmayer-Roig (K-S-R) theories. The following equations are obtained from F-Ftreatment_??_(CM* is the extrapolated value of CMat T=0°K) from F-F and K-S-R treatments where Tm is the characteristic temperature at which the vs. temperature curve shows amaximum, and all other notations used here are the same as in the previous paper (T. Kawaiand T. Ueyama: J. Appl. Polymer Sci., 3, 227 (1960)).These three equations mean that T, is higher for higher molecular weight, for higher ηpoint (poor solvent) and for larger flexibility of the chains. It is assured that the previoustreatment was qualitatively valid. From the data in literatures for polyisobutylene and polystyrene, T, is calculated and compared with the sign of d [η]/dT which was determined experimentally.The equations of 1st and 3rd cases can explain the experimental results with agood accuracy. The equation of 2nd case, however, seems to be less successful. The wellknown experimental result that the sign of d [η]/dT is negative for cellulose derivatives, may bemainly due to the polymer-solvent interaction rather than to the semi-flexibility of polymerchains.