Effect of hemicellulose extraction on water absorption and mold susceptibility of wood-plastic composites
- 作者：Omid Hosseinaei ; Siqun Wang ; swang@utk.edu ; Adam M. Taylor ; Jae-Woo Kim
- 关键词：Hemicellulose ; Wood&ndash ; plastic composite ; Water absorption ; Mold susceptibility ; Mechanical properties
- 刊名：International Biodeterioration and Biodegradation
- 出版年：2012
- 期刊代码：37_09648305
- 类别：ms
- 出版时间：July, 2012
- 卷：71
- 期：Complete
- 页码：29-35
- 文件大小：1207 K
摘要
The hygroscopicity of woody materials results in moisture absorption into wood-based composites, including wood-plastic composites (WPC). The objective of this research was to improve the water resistance and mold resistance of WPC by extraction of hemicelluloses from the wood raw material. The treatment may also eliminate extractives such as free sugars, starches, and lipids that can serve as food for fungi. Liquid hot water extraction was performed on southern yellow pine flakes under different temperatures (140, 155, and 170聽掳C) and over a period of 60聽min. Wood flour from extracted or control flakes was compounded with isotactic polypropylene in an extruder, both with and without a coupling agent. Injection molding was used to make tensile test samples. Wood-plastic composite samples were immersed for 5, 10, and 15聽wk in water and the water absorption and tensile properties of the samples were measured. The susceptibility of the WPCs to mold was evaluated also. The water absorption of samples decreased after extraction; this resulted in higher mechanical properties of WPCs from extracted wood flour after different periods of soaking in water. Extraction also resulted in improvement in mold resistance of the WPC.