✍ Scribed by H. Krik Johnston; S. Sourirajan
No coin nor oath required. For personal study only.
Viscosity measurements were made for dilute solutions of three grades of cellulose acetate (acetyl content 39.8%, molecular weight M̄~v~ 30270 to 46250) in acetone in the temperature t range of 10° to 35°C. The data satisfied the Mark‐Houwink equation, [η] = __K__M̄, where [η] = limiting viscosity number and K and 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]/dt versus M̄~v~ and 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.
📜 SIMILAR VOLUMES
Values of Q and A in the expression ~ = A exp (Q/RT)have been obtained for dilute solutions of fractions of a Bisphenol A polyearbonate in five solvents. The apparent activation energy of viscous flow Q varies with concentration c and molecular weight M according to where Q0 refers to the solvent a