Fast-Growing Poplar Wood Modified With Silica Sol/VAE

The fast-growing poplar wood is abundant in resources, high output and good processing performance. It grows rapidly, and growth cycle is short, which led to poor quality, low strength and small hardness, poor wear resistance, low mechanical strength and other shortcomings, restricted the scope of the use in furniture and wood products seriously. Improving and enhancing the related performance of fast-growing poplar wood is an urgent problem in expanding the use of poplar wood.In this article, we took the most important fast-growing plantation species-169poplar as the research object, aiming to improve the strength by modifying it with using silica sol/VAE as the modified liquid, by the method of vacuum pressure, mainly intended to be applied to furniture manufacturers. This article also studied the impregnating performance of modified liquid, and the complex process between liquid and modified poplar and process parameters; in the last, the scanning electron microscopy, infrared spectroscopy, X-ray diffraction analysis was performed to characterize the performance of modified wood, intending to provide a new way for the comprehensive utilization of fast-growing poplar wood:(1) Modified liquid has good film-forming, it is not brittle, and less crack; and it is with good stability and its storage time has been up to more than five months.Under certain conditions, using silica sol and25%of VAE according to certain proportion as modified liquid, the WPG increased by29.12%.(2)When the vacuum time before impregnating was45min, impregnating pressure was1MPa, impregnating time was60min, the average value of WPG of poplar wood impregnated with silica sol/VAE was37.72%, the compressive strength parallel to grain was56.42MPa, the MOR was86.25MPa, the MOE was6626.78MPa, compared with the untreated poplar increased by28.85%,44.2%and19.83%respectively. In the study, impregnation pressure can increase the rate of weight gain, however, higher pressure has adverse effect to wood mechanical properties.(3) Observation by SEM showed that the modified liquid penetrated into the interior of timber, deposited in wood cell lumen and catheter with physical adsorption or chemical binding irregularly after the curing. FT-IR results indicate that the SiO2particles of modified liquid can be combined with active groups of wood. According to the results of XRD, the (002) diffraction peak of modified wood hasn’t changed compared with poplar wood, however, the (004) and (101) diffraction peak has a slight change. It indicated that the modified liquid has certain influence on the crystallinity of modified wood and the effect was small.