Study and Characterization of LLDPE/Polyolefin Elastomer and LLDPE/EPDM Blend: Effect of Chlorinated Water on Blend Performance

Abstract

The objective of this study was to investigate the effects of two elastomers, namely ethylene butene copolymer (EBC) and ethylene propylene diene monomer (EPDM), on the physical, thermal and morphological properties of blend after exposure to chlorine. Blends of linear low-density polyethylene (LLDPE), ethylene-butene copolymers (EBC) and ethylene propylene diene ter polymer (EPDM) with different content were prepared by melt mixing in a twin-screw extruder. The LLDPE blend with EBC and EPDM were tested with water containing 50 ppm and 5000 ppm chlorine under static condition for 500 hr at 25°C and 80°C. Highest weight gain was observed for a higher concentration of chlorine for LLDPE/EBC-55 and LLDPE/EPDM-37 blend. It is seen that at 50 ppm chlorine concentration, the mechanical properties of LLDPE, LLDPE/EBC blend and LLDPE/EPDM blend remain unchanged. Chemical changes in the aged sample were checked by Infrared spectroscopy (FTIR), where increase in the O-H and C=O infrared bands was observed. The thermal characteristics of LLDPE, LLDPE/EBC blend, and LLDPE/EPDM blends were investigated using DSC and TGA which shows melting temperature and crystalline melt temperature remains unchanged while percent crystallinity was increased by 10 percent for LLDPE. Scanning electron microscope (SEM) showed that there was no formation of the micro cracks and cavities of LLDPE/EBC 73 blend and LLDPE/EPDM 73 blend after exposure to a higher concentration of chlorine. It indicated the excellent stability of prepared blend against chlorinated water