Theory of Dilute Highhyphen;Polymer Solutions (the Pearl Necklace Model)

摘要

A theoretical expression for the second virial coefficientA2of chain polymer solutions is derived. This accounts for the empirical relation betweenA2and molecular weightM,according to whichA2is proportional toMmdash;agr;. agr; has a value of about 0.23 over a suitable range of molecular weight. According to the theory, agr;ap;frac12;mdash;frac34;middot; (log1.684x), whenx,a variable proportional to the square root ofM,becomes very large. The temperature variation ofA2is also explained. Krigbaum and Flory's data on the molecular weight and temperature dependence ofA2are discussed.