【作者】 龙超；

【导师】 高志悦；

【作者基本信息】 内蒙古农业大学 ， 木材科学与技术， 2004， 硕士

【摘要】 本文以生长在我国西部沙漠地区的沙柳为原料，石膏为胶粘剂，通过调整添加剂的掺量，板坯的断面结构形式，原料配比以及成型压力等手段来改善沙柳石膏刨花板的性能。主要研究添加剂的掺量，板坯的断面结构形式，原料配比以及成型压力对板的静曲强度，平面抗拉强度，吸水厚度膨胀率等性能的影响,探讨改善沙柳石膏刨花板的性能。结果表明：1. 硼砂是石膏的缓凝剂，起着延长石膏水化时间的作用。因此，用沙柳生产石膏刨花板，可以通过添加硼砂的方法来改变石膏的水化过程。硼砂作为一种缓凝剂会影响石膏刨花板的强度，但为了保证正常生产，它又是一种不可缺的物质，因此我们应尽量将其用量控制在较小范围内。2. 加入适量的白水泥可以提高石膏本体的抗折强度，掺量为10%（白水泥/石膏粉）时增强效果最佳。白水泥对石膏水化的影响不大，有利于降低板的吸水厚度膨胀率。3. 加入适量的脲醛树脂胶可以提高板材的静曲强度、平面抗拉强度和握钉力，对吸水厚度膨胀率影响不大。4. 与单层结构板材相比，三层结构板材的综合性能指标较低。如采用三层结构板材，则对铺装的均匀程度要求相对较高，为了获得较高的强度，可以考虑用中刨花作表层原料，而用大刨花作芯层原料。5. 随着木膏比的增加，板材的静曲强度、握钉力和吸水厚度膨胀率均上升。6. 随着水膏比的增加，板材的静曲强度、平面抗拉强度和握钉力上升，弹性模量下降。7. 随着成型压力的增加，板材的静曲强度和弹性模量都上升。8. 根据试验结果，采用下列参数即可生产出高质量沙柳石膏刨花板。硼砂的掺量： 0.5%白水泥的掺量：10%脲醛树脂胶的掺量：6%板坯的断面结构形式：单层木膏比：0.30水膏比：0.30成型压力：2.0 MPa更多还原

【Abstract】 By adjusting the amount of addtive,the structure pattern on the board’s cross section , ratio of materials as well as the value of molding pressure ,the paper mainly studys on how to improve the quality of Salix Gypsum Particleboard (SGP),which is composed of gypsum as adhesive and Salix,a kind of shrub inhabitating western desert region of our country.To circumstantiate, the effects of above elements on the board’s property,such as Tensile Strength（MOR）,Inner Bond(IB) ,Thickness Swelling(TS) are focused on in this paper in order to improve the quality of Salix Gypsum Particleboard .The result shows that, 1. Borax is a sort of retarder during the hydration of gypsum,which can prolong this process. As a consequence, the hydration of gypsum can be changed by putting into borax when making Salix Gypsum Particleboard.As an essential substance in actual production,borax has negative effect on board’s strength,as a result, in order to ensure normal production,the amount of borax added must be controlled in a certain scope as small as possible. 2. Appropriate amount of white cement can increase the bending strengthen of gypsum itself ,which can reach its peak at 10 percent(white cement to gypsum).On the other hand, white cement has little effect on the hydration of gypsum ,but it does have good on TS. 3. To add proper amount of Urea Formaldehyde(UF)can enhance the MOR,IB, Screw Holding Power(SHP) of the board,while affecting little on TS. 4. The three-layer board’s comprehensive property is superior to that of the single –layer board .The degree of eveness while paving is highly demanded if three-layer board is adopted .Under such circumstances,it is preferable to use middle-sized particles as surface materials and large-sized ones for the inner so as to obtain high strength.5. The board’s MOR, SHP and TS climb with the increasing wood gypsum ratio.6.The board’s MOR,IB and SHP climb with the increasing wood gypsum ratio,while drop down with the MOE . 7. The board’s MOR and MOE rise with the increasement of molding pressure . <WP=4>8. According to the results of the experiments, Salix Gypsum Particleboard of high quality can be made using following parameters, the amount of borax added：0.5%the amount of white cement added：10%the amount of UF added：6%the structure pattern on the board’s cross section：single-layerthe ratio of wood to gypsum：0.30the ratio of water to gypsum：0.30molding pressure：2.0 MPa更多还原