杨木横向碱浸渍扩散的研究

通过自制的碱浸渍扩散装置对杨木横向碱浸渍扩散过程进行了研究。原料微观结构电镜分析发现,杨木边材的浸渍扩散性能优于心材。浸渍实验表明,杨木横向碱浸渍扩散过程可分为反应主导、反应与扩散并存、扩散主导3个阶段; 同时,通过单因素实验分析了温度、NaOH浓度、试样厚度、试样含水率等4个因素对碱浸渍扩散过程的影响。结果表明,温度与厚度对碱浸渍过程影响最大,NaOH浓度对与浸渍反应过程紧密相关的拐点值有一定影响,而含水率对碱浸渍扩散过程影响较小,但含水率饱和条件下的拐点值明显低于非饱和条件下的拐点值。

Study on the transverse alkali impregnating diffusion of poplar

The transverse alkali impregnating diffusion of poplar was studied with the self-made equipment. According to the scanning electron microscopy(SEM)analysis of the microstructure of raw material, impregnating diffusion performance of sapwood was better than the performance of heartwood. It was showed that there were three stages in the process of the transverse alkali impregnating diffusion of poplar, namely reaction-driven stage, reaction and diffusion coexistence stage and diffusion-driven stage. Meantime, the effects of main factors, which included temperature, concentration of NaOH, thickness of sample and moisture of sample, were investigated. The results showed that temperature and thickness of sample had significant effects on the alkali impregnating diffusion process. While, the concentration of NaOH influenced the inflection point mainly which had close link with reaction rate in the impregnating process. The moisture of sample had not remarkable influence on the process. But the inflection point value of water saturated sample was higher than that of water unsaturated samples in the moisture factor experiment.