Viscosity-temperature relationships for dilute solutions of cellulose derivatives: I. Temperature dependence of solution viscosities of ethyl cellulose

摘要: Abstract Viscosities of dilute solutions six fractions ethyl cellulose, molecular weight range 40,000–140,000, in solvents have been determined at different temperatures between 25° and 60°C. Log η is very approximately a linear function the reciprocal absolute temperature T. Values Q A expression = Ae RT are obtained. The apparent activation energy viscous flow, Q, linearly related to concentration c M by Q0 + KeMc A0e−KaMαc where A0 values for pure Ke, Ka, α constants particular cellulose-solvent system. Ka may vary slightly with M. An derived giving intrinsic viscosity terms α, M,