Recycling of crosslinked high-density polyethylene through compression molding

摘要

Crosslinkable high-density polyethylene (XHDPE) is used to manufacture large and rigid products such as fuel tanks using rotomolding. Currently, defective and postconsumer parts are not recycled and sent to landfills. Hence, recycling of this material through compression molding is the objective of this study. Thermal analysis revealed that the extent of crosslinking varied across the thickness of the rotomolded part due to the role played by oxygen in air. Despite the crosslinking, the recycled XHDPE (RXHDPE) could be remelted with higher viscosity than the virgin XHDPE (VXHDPE). Consolidation studies indicated that both the RXHDPE and the VXHDPE could be compression molded to a density of 0.952 g cm(-3). However, higher consolidation stress is required for the RXHDPE when compared to the VXHDPE to realize the same density. The RXHDPE, compression molded at 1.6 MPa and 230 degrees C, had properties similar to those of the VXHDPE molded at 0.32 MPa. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48145.