Properties of paper mill sludge–wood fiber–HDPE composites after exposure to xenon-arc weathering

Abstract

We used paper mill sludge (PMS) to substitute for part of the wood fibers (WF) used to reinforce high density polyethylene (HDPE). The resulting composites were subjected to xenon-arc weathering. The composite filled with limited PMS (under 10 %) had mechanical properties and aging resistance similar to those without PMS. The composites containing more PMS faded and cracked more readily than those without PMS. Based on the carbonyl index, crystallinity, and wood index, PMS appeared to accelerate the degradation of composites during weathering. Adding PMS to WF–HDPE composites reduced the weathering resistance, and this reduction was not significant if the PMS content did not exceed 20 % of the wood fibers. Therefore, PMS could be used as a reinforcement in wood-plastic composites at levels less than 20 % of the wood fiber content.

Keywords

Wood fiber / Paper mill sludge / HDPE / Composites / Xenon-arc weathering

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