DRAWING OF POLY (VINYL CHLORIDE) POLYMERIZED AT LOW TEMPERATURE (PART 1)

Abstract

Part. 1) Fiber were prepared from various kinds of polyvinyl chloride (PVC) polymerized at different temperature under various drawing conditions. The following results were obtained from the measurements of the density, the heat shrinkage and the X-ray difraction in these different kinds of fibers.1) The observation of the relation between the temperature and the degree of extention at break. shows the existence of the temperature range where the degree of extension at break becomes. very high. This optimum temperature range for extension coincides with the heat treating temperature range which renders the highest density And as the temperature of polymerizaion is lowerd, that optimum temperature range shifts to the higher temperature.2) Within the optimum temperature range for extention the density increases almost linearly with the degree of extention, but below this almost no density increase was observed up to the degree of extention of 400% and it begins to increase when the degree of extention exceeds 400%. At the temperature range higher than this optium temperature range the increase of the density is observed mainly before the degree of extention reaches 400% and the increase of thedensity over 400% extention was not remarkable.3) Corresponding to the variation in the density, the dimension of the crystallite determined from the X-ray study increases with the increased dgree of extention. And the degree of the increase of the dimension of crystallite is higher in the PVC polymerized at low temperature.