Effects of biocide treatments on durability of wood and bamboo/high density polyethylene composites against algal and fungal decay

Abstract

The main objective of this study was to investigate the algal and fungal resistance of biocide‐treated wood flour (WF)/high density polyethylene (HDPE) and bamboo flour (BF)/HDPE composites. The biocides included 4,5‐dichloro‐2‐octyl‐isothiazolone (DCOIT), zinc pyrithione (ZPT), and carbendazim (MBC). Resistance to algae and fungi was evaluated by artificially accelerated tests. Treated and untreated samples were exposed to algae (Chlorella vulgaris, Ulothrix sp., Scenedesmus quadricauda, and Oscillatoria sp.) and fungi (Coriolus versicolor and Poria placenta) for 21 days and 12 weeks, respectively. The volatile components of WF and BF extractives were analyzed by gas chromatography‐mass spectrometry (GC‐MS). The results indicated that incorporation of DCOIT, ZPT, and MBC effectively enhanced the durability of WF/HDPE and BF/HDPE composites against algal and fungal decay. Accordingly, DCOIT, ZPT, and MBC can be used as potential biocides for both WF/HDPE and BF/HDPE composites. GC‐MS analysis suggested that palmitic acid, oleic acid, stigmasta‐3,5‐dien‐7‐one, and vanillin in WF possibly provided some resistance to fungal attack, whereas di (2‐ethylhexyl) phthalate and linoleic acid in BF were responsible for algal resistance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45148.

Experimental study on durability of wood–plastic composites by coupling dry–wet cycles and seawater environment

“…2 Nevertheless, because each material is susceptible to degradation due to aging, the premise that WPC materials can durably perform according to their initial design has been questioned. Because WPC materials are directly affected by aging factors, such as ultraviolet radiation, [3][4][5] biological attack, [6][7][8] freeze-thaw fatigue, 9 and water degradation, 10 thorough research on their durability is necessary.…”

Effects of fungal decay on properties of mechanical, chemical, and water absorption of wood plastic composites

“…Severe changes in the chemical structures of lignin, cellulose, and hemicellulose of wood fillers are always observed after decay fungi exposure, which usually accompanied with substantial losses in weight and strength for the decayed WPCs. [12][13][14][15][16] In general, deterioration of physical and mechanical properties of WPCs by fungi is the result of combined action of both decay and mold fungi.…”

“…10,11,27 It has been proved that the chemical compositions of wood extractives, such as, tannins, fatty acids, aldehydes, ketones, sugars, and starches have significant effects on the susceptibility of WPCs toward fungal attack. 10,11,14,28,29 In our recent work, we have explored the influences of mold susceptibility, total soluble sugar contents and chemical components of wood fibers species on mold resistance of WPCs filled with poplar, moso-bamboo, Chinese fir, Ramin, white pine, and rubber wood. 11 However, we have not yet clarified the effects of these above-mentioned wood species on the resistance against decay fungal of WPCs.…”

“…Meanwhile, the various chemical extractives of wood species are also taken into account while evaluating and predicting the performance of natural durability of wood species 10,11,27 . It has been proved that the chemical compositions of wood extractives, such as, tannins, fatty acids, aldehydes, ketones, sugars, and starches have significant effects on the susceptibility of WPCs toward fungal attack 10,11,14,28,29 …”

Mussel-Inspired Polydopamine as a Green, Efficient, and Stable Platform to Functionalize Bamboo Fiber with Amino-Terminated Alkyl for High Performance Poly(butylene succinate) Composites

“…This disadvantage restricts the potential of BFs as reinforcements, particularly for PBS composites [ 10 ]. In addition, the as-reinforced composite with high fiber content often exhibits low water resistance, which further renders the composite vulnerable to fungi and structural instability, markedly reducing durability and service lifetime [ 11 ]. Thus, surface modification and functionalization of BFs are critical in the fabrication of high-performance PBS composites to obtain good interfacial compatibility and anti-water capability.…”