SYNERGISTIC EFFECT OF LAYERED DOUBLE HYDROXIDE AND EPOXIDIZED OILS ON THE THERMAL STABILIZATION OF POLYVINYL CHLORIDE
ABDUL AHAMAD *
School of Chemical Sciences, North Maharashtra University, Jalgaon-425001, M.S., India.
D. G. HUNDIWALE
School of Chemical Sciences, North Maharashtra University, Jalgaon-425001, M.S., India.
*Author to whom correspondence should be addressed.
Abstract
This work reports the studies on synergistic effect of layered double hydroxide with epoxidized oil (sunflower and soybean oil) on the thermal stabilization of poly(vinyl chloride). For the study Ca-glutarate was prepared and epoxidation of sunflower oil (ESO) was carried out in the laboratory. The Ca/Zn based compounds along with layered double hydroxide (LDH) were used for the stabilization of PVC. Synergistic effect of LDH with Ca/Zn stabilizer on the thermal stabilization of PVC with and without the presence of epoxidized oils was studied. Thermal stability of PVC was determined by Congo red test as a stability time while the discoloration of the PVC sheets were examined in the oven test. Synergistic effect of LDH with epoxidized oils on the thermal stability of PVC was substantially observed with better stability time. The synergism of LDH in presence of both the epoxidized oil (sunflower and soybean oil) results in better stabilizing efficiency of PVC which was comparable for both the oils. It is suggested that the LDH and epoxidized oils react with liberated HCl during the degradation of PVC by ion exchange mechanism. It is also projected that the participation of epoxy ring present in epoxidized oils react during the release of HCl and further prevents the dehydrochlorination reaction of the PVC.
Keywords: Thermal stabilization, synergistic effect, dehydrochlorination, Congo red