Strong, durable, and aging-resistant bamboo composites were prepared by silver electrochemical and high-voltage electrostatic field (HVEF) treatments. Surface morphology, chemistry, and wettability were investigated after the treatments. Changes of rheological and curing characteristics of resin were determined. After preparation, the aging resistance and mechanical properties of bamboo composites were tested. The results showed that under the HVEF treatment, silver interacted with hemicellulose and lignin of bamboo and nanosized silver particles distributed evenly on the surface of bamboo. On the other hand, nanosilver particles directly interacted with the molecular chain of the resin by strong physical/chemical forces. According to the chemical and rheological results, the cross-linking degree of phenolic resin was proved to be increased by the catalysis of silver. An increment of density along the bonding line as well as mechanical properties of the composites was found. These findings prove that silver electrochemical and HVEF treatments are effective to regulate the structures and properties of bamboo composites and may also be relevant to the development of new bamboo engineering composites.

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In order to improve hydrophobic characteristics which will affect the service performance of fast-growing poplar due to growing bacteria in the humid environment. In this study, a simple method was proposed to treat poplar via the high voltage electric field (HVEF) with copper as the electrode plate. Scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD) and contact angle tester were adopted to evaluate the surface morphology, surface group of poplar, crystallinity and wettability under HVEF. It was found by SEM that a large number of copper particles were uniformly attached to the surface of poplar. In all three sections, the weight percentage of the Cu element was accounting for more than half. The diffraction peaks of copper-containing compounds appeared in the (XRD). FTIR analysis confirmed that the reaction between copper and poplar took place. The surface contact angle of three sections of poplar increased in the following order: cross section < radial section < tangential section (increased by 34°, 45°and 53°, respectively). An environmentfriendly and efficient method of HVEF treating fast-growing wood with copper as the electrode plate can promote its outdoor application.