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It has been reported that pinewood residue/recycled high density polyethylene composites with 40 wt% of wood were attacked by termites native to the Yucatan Peninsula (Nasutitermes nigriceps). Thus, this article gives account of how effective environmentally friendly borates are (i.e. borax and zinc borate) to protect this kind of composites. Before biotic exposure, composites’ samples were subjected to 1000 and 2000 h of accelerated weathering, using a ultraviolet-type accelerated tester equipped with UVA-340 fluorescent lamps and respectively impregnated with 1, 2, and 3% aqueous solutions of both borates, following the ASTM D 1413 standard test method as reference. A reduction in the treated samples’ weight loss was observed, which indicated that they increased their resistance to termite attack. No weight losses occurred when the solutions with 3% of both borates were respectively used. Additionally, scanning electron microscopy revealed that these solutions did not damage the composites’ surface. The results show that both borates experimented with have the potential to be used as termiticides for wood–plastic composites without damaging the environment. [ABSTRACT FROM AUTHOR]

Although wood–plastic composites (WPCs) are materials widely used in the construction industry, their durability constitutes a serious issue especially when used for outdoor applications. Therefore, this work gives account on the effect of biotic and abiotic degradation agents on two different WPCs prepared from recycled high-density polyethylene (HDPE) and pinewood residues. Two aspects were evaluated, namely mechanical properties and aesthetics. Compression-molded samples obtained from two different formulations based on 40% of wood and 60% of HDPE, containing 0 and 5% of coupling agent with respect to wood content, were subjected to 0, 1000 and 2000 h of accelerated weathering (AW), using an ultraviolet-type accelerated tester equipped with UVA-340 fluorescent lamps. Afterward, the aged specimens were exposed to attack by termites (TA) of the species Nasutitermes nigriceps for 15 and 30 days. Tensile properties after AW and TA were assessed using an Instron 5500R (1125) universal tester. Similarly, the aesthetic aspect was studied to evaluate the color changes on the specimens’ surfaces using a Minolta CR-200 Chroma Meter. The results of this work show drops in the mechanical properties of both composites that were not significant, even after being exposed to 2000 h of AW in combination with 30 days of TA. However, their aesthetics was seriously affected by both degradation agents, as reflected by the variations registered on the total color change and relative lightness of the tested samples. [ABSTRACT FROM AUTHOR]