Effects of ZnAl layered double hydroxide and benzimidazole derivative on the dechlorination of poly(vinyl chloride)

Abstract Layered double hydroxides (LDHs) that are generally used as thermal stabilizers of poly(vinyl chloride) (PVC) can also have catalytic effects on the dechlorination of PVC. In this study, benzimidazole derivative (OBPB) modified ZnAl-LDH (OBPB@ZLDH) was synthesized and incorporated into PVC, and the effects of OBPB@ZLDH and the physical blend of OBPB and ZLDH (OBPB/ZLDH) on the dechlorination of PVC were investigated by Congo red test and discoloration test. The results indicated that OBPB/ZLDH could improve the thermal stability of PVC. The composition and chemical structure of PVC composites after discoloration test were studied by energy dispersive X-ray spectroscopy and attenuated total internal reflectance-infrared spectroscopy. The results revealed that the products derived from the reaction between HCl released in the thermal degradation of PVC and OBPB/ZLDH could accelerate the dechlorination and oxidization of PVC at low temperature. Therefore, it has potential applications in the dechlorination of PVC to prepare hydrochars for use as alternative fuels at low temperature.