Entanglement Effects in Concentrated Polymer Solutions from Viscosity Measurements

摘要

The viscositymdash;molecular weight relation for the system polymethyl methacrylatemdash;diethyl phthalate has been measured. Polymer concentrations of 0.10, 0.15, 0.20, and 0.25 g/cc have been used. No variation in entanglement molecular weightMein the range 30deg;mdash;80deg;C was found. Theoretical predictions for the dependence ofMeon concentration have been confirmed. After correcting the data for variation inTgwith molecular weight, the dependence of viscosity on molecular weight predicted by theory is confirmed. Possible reasons are given for the discrepancy between the present conclusions concerningMeand those arrived at from considerations of dynamic data on the same system.