Study of Wood-Plastic Composites with Reused High Density Polyethylene and Wood Sawdust

In recent years, concerns about environmental preservation have motivated industries to adapt towards more environmentally friendly materials, resorting for this to recycled and waste materials. This has been the center for a growing number of research studies to enable less and less virgin materials waste [1], [2]. The use of recycled thermoplastics has been considered for the production of wood and plastic composites in recent years [3]. New materials have been developed with a view to developing eco-composites, materials with several advantages, both at an environmental level and an ecological level, including natural polymers[4]. Solid plastic waste from polymers such as high density polyethylene is creating new challenges for an industry that is seeking greater waste utilization to ensure products that are efficient ecologically and environmentally friendly [5,6]. The cost and quality of these composites depends on the waste type incorporated, on the material and the processing route used [4]. The sawdust waste produced by the sawdust industry is about 5% per tree log, which makes this an important renewable raw material [2]. The objective of this study was to investigate composite material properties developed from reused HDPE thermoplastic material from the thermoplastics injection industry and pine sawdust from the lumber industry. The materials were developed with three different volume fractions of pine sawdust and two different particle sizes, mixed in a double screw extruder. A validation of a processing route - injection molding - was also performed.