Viscosity–temperature relationships for cellulose acetate–acetone solutions

Viscosity measurements were made for dilute solutions of three grades of cellulose acetate (acetyl content 39.8%, molecular weight M̄v30270 to 46250) in acetone in the temperaturetrange of 10° to 35°C. The data satisfied the Mark‐Houwink equation, [η] =KM̄ , where [η] = limiting viscosity number andKand α are Mark‐Houwink constants. The values of [η] and α decreased with increase in temperature, and straight‐line correlations were obtained for −d[η]/dtversus M̄vand log η versus 1/T(absolute temperature). The results are discussed in terms of solution properties of cellulose acetate in acetone and their possible relevance to reverse osmosis membrane science.