双醛纤维素胶合玉米秸秆制备人造板的研究

Preparation of Particleboard by Gluing Corn Stalk with Dialdehyde Cellulose

采用高碘酸钠氧化纸浆纤维制备双醛纤维素。利用双醛纤维素的醛基与玉米秸秆上的羟基,生成半缩醛结构胶合玉米秸秆制备不含甲醛的人造板。研究热压温度、密度和双醛纤维素用量对人造板物理性能的影响。利用扫面电镜观察人造板的弯曲断面形貌,结果表明,静曲强度和弹性模量随热压温度的升高和双醛纤维素用量的增加先上升后降低,而随着人造板密度的增加有显著提高。提高热压温度、增加密度和双醛纤维素用量能够降低人造板的吸水厚度膨胀率,改善人造板的抗水性能。人造板的弯曲断面分析表明,双醛纤维素填充在玉米秸秆之间缝隙之中,将玉米秸秆紧紧胶合在一起,起到了胶黏剂的作用,从而提高人造板的物理机械性能和抗水性能。

Dialdehyde Cellulose was prepared through oxidation of pulp fiber with sodium periodate.The formaldehyde free particleboard of corn stalk was prepared by gluing the corn stalk with hemiacetal structure,which was formed from aldehyde groups of dialdehyde cellulose and hydroxyl groups of corn stalks.The effects of the hot pressing temperature,density and the amount of dialdehyde cellulose on the physical properties of the corn straw particleboard were investigated.The bending section morphology of the particleboard was observed by scanning electron microscope（SEM）.It was found that MOR and MOE first increased and then decreased with the increase of the hot pressing temperature and the amount of dialdehyde cellulose,but increased significantly with the increase of density.The increase of the hot pressing temperature,the density and the amount of dialdehyde cellulose could reduce TS of the particleboard,and improved the water resistance of the particleboard.The bending section analysis of the particleboard showed that the dialdehyde cellulose filled in the gaps between the corn stalks,and tightly bonded corn stalks,which acted as an adhesive,thereby improving the physical and mechanical properties and water resistance of the particleboard.