Flow-Induced Crystallization of Syndiotacticity-Rich Polyvinyl Alcohol) From Dimethyl Sulfoxide-Water Solution

The flow-induced crystallization of syndiotacticity-rich poly (vinyl alcohol) from the dimethyl sulfoxide (DMSO)/water solutions was studied. With the DMSO content of ca. 5 vol%, the rate of crystallization was highest and fibrillar crystals formed near the surface of the solution at the initial stage of stirring. An expansion of polymer coil due to an increased solvation is considered to enhance the rate of crystallization. A stretching of the polymeric chains at the surface due to adsorption is also considered to accelerate the formation of nucleus.