Chemical Modification Of Polyvinly Chloride (PVC) In Wet Process

Polyvinyl chloride (PVC) is a widely used polymer material in various aspects of our daily life. In this work, we studied the dehydrochlorination of PVC by strong and weak base in THF or DMSO solvent at various conditions. The as-prepared dehydrochlorinated PVC (DHPVC) is characterized using ion chromatography, FTIR, TGA, SEM and GPC. The influencing factors for the dehydrochlorination of PVC were also studied, including temperature, reaction time and water content in the reaction mixture. The results indicate that PVC can be dehydrochlorinated efficiently at appropriate conditions, forming DHPVC with varying chlorine contents.Chemical modification of DHPVC with maleic anhydride was achieved at varying reaction conditions and the resulting products were analyzed and characterized by FTIR, TGA, SEM, GPC and titration method for various purposes. The characterization results indicate clearly the chemical grafting of maleic anhydride to the DHPVC chain, through the massive increase in the average molecular weight of the grafted PVC.Besides, we also studied the chlorosulfurization of PVC by sulfuryl chloride (SO2Cl) via radical reaction in THF solvent with AIBN as catalyst. The synthesized PVC-g-SO2Cl was characterized by using various characterization techniques such as FTIR, TGA, SEM and GPC. The PVC-g-SO2Cl was found more flexible and elastic than PVC precursor.It is concluded from the above results that PVC can be de-hydrochlorinated by strong base as well as weak base, forming DHPVC, which can be further modified by maleic anhydride via radical grafting. Besides, PVC can be directly reacted with sulfuryl chloride, forming PVC-g-SO2Cl with a higher elasticity than PVC.