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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]

Solid urban wastes are a primary source of local and global contamination. One approach to slow their accumulation is by using them to obtain addedvalue products. One common example of these waste materials is the fiber from the husks of coconuts, i.e. coir. However, it is also known that microorganisms such as fungi can attack products containing natural fibers. In this respect, this study aimed to evaluate how the mechanical properties of an extruded composite made of 60% recycled HDPE and 40% discarded coir were affected due to accelerated weathering and Phanerochaete chrysosporium attack. The effect of P. chrysosporium on the materials' mechanical properties before and after weathering, using an accelerated weathering (AW) test device, was evaluated by means of tensile and flexural analysis following ASTM standards. Samples were also characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). FTIR spectroscopy and SEM showed that both types of treatment degraded the surfaces of the tested samples. However, the mechanical performance was not seriously affected, which means that other fungal species would affect the composites to a lesser extent. [ABSTRACT FROM AUTHOR]

Wood-plastic composites (WPCs) are considered to be highly durable materials and immune to any type of biological attack. However, when one of these composites is exposed to accelerated weathering, its surface is affected by the appearance of cracks, which constitute an ideal access route for biotic agents. Although the destruction of wood caused by termites is recognized worldwide, information on their effects on WPC-based products is scarce. Thus, in this study, we aimed to examine the effects of termite attacks on weathered and nonweathered pinewood residue/recycled high-density polyethylene composites. In this study, WPCs with 40 wt % wood were prepared. Test samples obtained by compression molding and profile extrusion were subjected to weathering cycles for 1000 and 2000 h with a UV-type accelerated tester equipped with UVA-340 fluorescent lamps. Afterward, specimens were exposed to the attack of higher termites ( Nasutitermes nigriceps) native to the Yucatan Peninsula. Subsequently, flexural mechanical essays, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) analyses were performed. FTIR spectroscopy and DSC showed that the surfaces of the compression-molded specimens were degraded to a higher extent because of the accelerated weathering. The microscopy results revealed that severe damage was caused by the termites on the surface of the compression-molded samples. Statistical analysis of the mechanical test results showed that biotic attack produced significant changes in the samples previously exposed to accelerated weathering. The results show that the processing method directly affected the sample performance because of differences in the surface composition. The profile-extruded composites seemed to better resist termite attack. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]