Effect of waste glass reinforcements particle size on some properties of HDPE-based composites

Composites were produced by mixing waste glass powder (WGP) of different particle sizes (from 841 μm to smaller than 177 μm) with high-density polyethylene (HDPE) to determine the effects of WGP particle size on some properties of HDPE. WGP was added into HDPE at a rate of 25 wt. % and then mixed with an extruder. As WGP particle sizes decreased, the densities of the composites increased. Adding WGP to HDPE increased the modulus and hardness values of the composites. The lowest flexural modulus was 1079 N/mm2 in the composite with WGP between 400 and 841 μm, and the highest flexural modulus was determined to be 1671 N/mm2 with WGP smaller than 177 μm. In addition, WGP decreased the flexural and tensile strengths of the composites. The flexural strength of neat HDPE was determined as 37.2 N/mm2, the lowest flexural strength was determined as 31.2 N/mm2 (for WGP size 400 – 841 μm) and the highest flexural strength was determined as 33.2 N/mm2 (for WGP smaller than 177 μm). According to the thermal analysis results, WGP slightly increased the melting temperature of the HDPE. However, the particle size difference of WGP did not affect the melting temperatures of the polymer much. The melting temperature of neat HDPE was 127.7 °C and the highest melting temperature was determined as 131.3 °C for the composite with WGP filler size between 177 and 250 μm.