Coal-Filler-Based Thermoplastic Composites as Construction Materials: A New Sustainable End-Use Application

Abstract

This paper reports investigations into coal's viability as an alternative filler to wood flour in wood plastic composites (WPCs)a class of materials used in building applications in lieu of pressure-treated wood coal plastic composites (CPCs) were fabricated with 15−60 wt % coal combined with high-density polyethylene and their physical (mechanical, water absorption, and metal leaching) and chemical (oxidative degradation and flammability) properties were compared with commercial WPCs. In addition, mass and energy balances (10 ton/h basis) and life cycle analyses (60 wt % filler and 1 ton basis) were conducted on CPCs and WPCs to assess environmental impact during manufacturing. At 60 wt %, CPCs had higher flexural strength, slower oxidative degradation and burn rate, and lower water absorption in comparison to commercial WPCs, suggesting better performance and stability in building applications. Furthermore, CPC manufacturing showed 44% lower greenhouse gas emissions and 62% less energy usage in comparison with WPC. These results indicate that the direct utilization of coal as a filler in construction composite applications may yield lower-cost products with lower associated emissions and energy demand compared to that of existing WPC materials, potentially yielding a more sustainable end use for coal than current uses such as power production.

Flammability and thermal stability of thermoplastic-based composites filled with natural carbon

“…Note, a previous study highlighted the antioxidation impact of coal on polymer composites. 14 Similar mechanisms for WPC decomposition under air were proposed in the literature. 13,28 Ignition temperatures of CPC FIT is the minimum temperature at which flammable volatiles released, due to heating of a material, ignites with the presence of a pilot flame.…”

“…Recently, several types of coal have been investigated to replace wood flour used in polymer composites. 14,15 A former study has shown that coal plastic composite (CPC) outperformed several commercially available WPC products in strength, oxidation, burn rate, ignition, and water absorption. 14 In addition, a preliminary life cycle analysis also indicated CPC manufacturing requires less energy and generates less greenhouse gas emissions than WPC manufacturing.…”

“…14,15 A former study has shown that coal plastic composite (CPC) outperformed several commercially available WPC products in strength, oxidation, burn rate, ignition, and water absorption. 14 In addition, a preliminary life cycle analysis also indicated CPC manufacturing requires less energy and generates less greenhouse gas emissions than WPC manufacturing. 14 The United States possesses millions of tons of previously mined coal resources stored in coal waste impoundments.…”

“…14 In addition, a preliminary life cycle analysis also indicated CPC manufacturing requires less energy and generates less greenhouse gas emissions than WPC manufacturing. 14 The United States possesses millions of tons of previously mined coal resources stored in coal waste impoundments. 16 Coal waste impoundments contain fine coal particles and other mineral matter generated at a mining facility.…”

The effect of thermal, flammability, and mechanical properties of wood plastic composites made from recycled food-packaging LDPE and eco-friendly phytic acid

“…Among all composites, the 30L55WF-PA(N), containing 55% WF-PA(N) in the LDPE matrix, presented a flame spread rate of 16.06 mm/min. Generally, such phenomenon could be ascribed to the fire retardant fillers(WF-PA(N)) in polymer matrix (LDPE) that restrain composite combustion associated with char layer formation on the surface inhibiting internal layers from the external heating environment (Nicole et al, 2010;Umemura et al, 2014;Al-Majali et al, 2019). Therefore, it is clear that the addition of phytic acid modified wood (WF-PA(N)) not only can significantly improve in flame retardant properties, but help to reduce the carbon footprint of plastics through reusing wood flours to meet the environmental protection trends.…”