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The focus of this study was to observe the properties of bamboo plastic composites modified with a self-made modifier, 18 acyl-dopamine (0, 0.25, 0.50, 0.75, 1.00, and 1.25 weight percent [wt%] based on the dry weight of bamboo powder). The effects of the modifier were demonstrated by measures of mechanical properties, water absorption, thermal stability, and scanning electron microscopy (SEM). The results revealed that 18 acyl-dopamine could be used as an effective modifier of bamboo powder/high-density polyethylene composites. When the modifier was increased, the toughness of the composite deteriorated, and the strength and rigidity improved. This indicated that when the dosage became higher, the compatibilization became stronger, and the toughening effect became worse. Based on the experimental data, a small dosage modifier acted as a toughening agent; as the dosage increased to 1.0 wt%, the compatibility began to appear. The modifier reacted with the hydroxyl groups on the surface of the bamboo powder, which caused the bamboo powder to absorb less water, so the thickness expansion rate was lowest at 1.25 wt%. The pyrolysis peak of bamboo powder and plastic showed a tendency to be close to each other, indicating that the interface was improving. Based on the equation of Flynn-Wall-Ozawa, as the dosage of the modifier increased from 0.50 to 1.25 wt%, the apparent activation energy also increased. The SEM analysis showed the binding between bamboo powder and the plastic matrix was strongest when the modifier dosage was 1.25 wt%., Bamboo plastic composites have many advantages. Compared with traditional glass fiber and mineral filler reinforced material, bamboo is an environmentally friendly natural filler for composites with lower density and cost, [...]

Formaldehyde-based resin and petroleum-based plastic are often used as an adhesive in plywood manufacturing, which has an adverse effect on people's health and the global environment. We have investigated the plywoodlike composite with wood veneer (WV) and poly-[beta]-hydroxybutyrate film (PHBF) as a novel formaldehyde-free and environmentally friendly composite (WV-PHBF). The composite was prepared with three veneers, and the PHBF placed between adjacent veneers varied from 22.5 to 112.5 g/[m.sup.2]. The composite was hot pressed at 170[degrees]C for 70 s/mm under a pressure of 1.0 MPa. Furthermore, the WV-PHBF with an adhesive dosage at 67.5 g/[m.sup.2] was modified with three modification methods: silane coupling agent (KH-550), alkaline solution (NaOH), and polydiphenylmethane diisocyanate (p-MDI). Results showed the following: (1) under the untreated condition, a composite with more than 67.5 g/m adhesive will meet the Chinese National Standard (GB/T) 9846-2015 of bonding and bending strength requirements, and 90.0 g/[m.sup.2] was the best; (2) the KH-550 and p-MDI treatment had a positive effect on WV-PHBF, but NaOH mainly had an adverse effect; (3) the physical--mechanical properties of the composite with 67.5 g/m adhesive content being processed by 1 percent by weight (wt%) KH-550 or 2 wt% p-MDI was better than WV-PHBF with 90 g/[m.sup.2] adhesive content, especially in bonding strength; (4) statistical analysis shows that 1.0 wt% KH-550 significantly improved the bonding strength properties of WV-PHBF, and water-resistance properties were significantly improved by 2.0 wt% of p-MDI also; and (5) morphological observation shows that KH-550 and p-MDI treatments increase the interfacial compatibility between WV and PHBF of the composites., With people's awareness of environmental protection, the impact of the living environment on health status is gaining increasing attention. Plywood, as a main product of China's wood-based panel industry (Wang [...]

The purpose of this paper is to discuss the influence of different proportions of bamboo pulp residue on the bending strength, the static bending strength, the water absorption rate, and the microstructure of wood flour/phenolic resin composites. The level of bamboo pulp residue ranged from 0 to 30 percent. According to the optimum technological parameters of the pretest, the resin content, the molding temperature, and the molding time were controlled within 51 to 54 percent, 152[degrees]C to 160[degrees]C, and 51 to 60 s/mm, respectively. Compared with the control group, there were remarkable improvements in the mechanical properties, indicating that the bending strength, the static bending strength, and the water absorption rate increased by 39, 31, and--6 percent, respectively. The greatest level of bamboo pulp residue was 20, 20, and 10 percent for the bending strength, the static bending strength, and the water absorption rate, respectively. All of the above proved that the wood flour/phenolic resin composites can be modified by adding bamboo pulp residue., According statistics from 2016, the forest coverage rate in China is approximately 21.93 percent, far below the world's overall forest coverage of 30 percent (Yi 2017). Also, China is one [...]