Observation and Analysis of Gypsum Particleboard using SEM

The microstructures of gypsum board and gypsum particleboard were observed by SEM. The effects of retarder and waterproof agent on the shape and the average dimension of the gypsum crystal were discussed. The mechanism was investigated as well. Four typical instances, i e, the gypsum crystal shape, the gypsum combined with particles on the particles surface, the gypsum combined with particles on the wood cross section and the gypsum combined with particles inside the wood cell cavity were selected and observed. Furthermore, the agglomeration and cementation mechanism between gypsum and particle were studied.     

Mechanical properties of nano SiO2 filled gypsum particleboard

Nano SiO2 was filled into gypsum particleboard. Effect of the amount of nano SiO2 particles filled, ultrasonic dissipating duration and treating the nano particles with different coupling agents on the mechanical properties of the board were studied respectively. The results show that nano SiO2 is helpful for the improvement of the properties. Adding 3%（mass fraction） nano SiO2 is the best for the improvement of both modulus of rupture（MOR） and modulus of elasticity（MOE） of the boards formed at 30 ℃ or 40 ℃. For the boards formed at 30 ℃, their MOR and MOE can be improved by 8.77% and 12.24%, and MOR and MOE of the boards formed at 40 ℃ can be improved by 44.44% and 108.38%.3% is also the best addition proportion to improve internal bond（IB） of the boards formed at 30 ℃, while 5% is the best for that of the boards formed at 40 ℃. At room temperature, dissipating nano Si02 into flake by ultrasonic has better effect on the properties of the final products. Through ultrasonic treating for 1 h and the best treating duration, the MOR and MOE can be increased by 41.99% and 47.80%. In addition, different coupling agents have different effects on the final properties too, and silane coupling agent KH570 is better for the improvement of properties of the boards formed at room temperature.     

Effects of dowels produced from various materials on withdrawal strength in MDF and Pb

Wood dowels are commonly used in the construction furniture, but little information is available about the additive effects of dowels on the ultimate withdrawal strength of single or multidowel joints. This study was carried out to determine the tensile strength of 10‐mm‐diameter dowels produced from medium‐density fiberboard (MDF), plywood, scotch pine (Pinus sylvestris L.), and beech (Fagus orientalis lipsky), bonded parallel and vertical to the surface of MDF and particleboard (Pb) with poly(vinyl acetate) (PVAc) and Desmodur‐VTKA (D‐VTKA). Tensile strength was applied to the dowels according to the procedure in the ASTM‐D 1037 standard. The effects of dowel species, direction of tensile, composite material, and type of adhesive on tensile strength were determined. The results showed that the highest tensile strength was obtained in beech dowels bonded vertically with PVAc adhesive to the surface of MDF at 7.91 N/mm². If the dowels used in furniture production are subjected to great tensile strength, beech dowels bonded with PVAc adhesive on MDF should be used. However, when dowels produced from MDF and plywood waste are used, they also can produce positive results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 531–535, 2003     

喷水工艺对木质素胶黏剂刨花板性能影响的研究

就板坯制备工艺对采用木质素胶黏剂制备刨花板进行试验研究,通过设计正交试验,获取和分析所制备刨花板的物理力学性能,探讨制板工艺过程对木质素胶黏剂刨花板性能的影响.试验结果表明,制板过程中,采用喷水工艺对木质素胶黏剂刨花板的静曲强度和弹性模量影响最大,对24 h吸水厚度膨胀率影响次之,对内结合强度影响较小;随着喷水量的增大...     

利用废弃刨花板制造再生刨花板的工艺研究

以废弃刨花板再生刨花为原料,用正交试验法压制再生刨花板,研究再生刨花的使用比例、施胶量、热压时间对再生刨花板静曲强度和内结合强度的影响,并提出了生产再生刨花板的最佳热压工艺。     

刨花板翘曲变形产生的原因及其解决办法

对当前刨花板产品质量状况进行了简单评述,对刨花板翘曲变形产生的原因进行了详细分析,并提出了相应的解决办法。     

谈谈E1级刨花板生产过程中的几点体会

介绍在采用E_1级脲醛树脂胶的情况下,生产E_1级刨花板对设备、胶粘剂、刨花制备、热压工艺及检测的要求。     

E1级刨花板制备工艺的研究

研究讨论了热压温度、热压时间、板坯含水率、固化剂种类及用量等刨花板生产工艺参数对刨花板中游离甲醛含量的影响,从而对刨花板的生产工艺进行优化,得出了最佳工艺参数,并在工厂的批量生产中得到了验证。     

不同密度和厚度对蓖麻秆刨花板性能的影响研究

在蓖麻秆刨花板最佳工艺条件下,研究了不同厚度和密度对板材性能的影响,结果表明,当板材的厚度为10mm时,板材的各项性能随板材密度的增加而增大,当板材的密度大于0.64g/cm3时,板材的各项性能除吸水厚度膨胀率以外,其余各项性能均可满足国家普通刨花板标准对室内装饰和家具用材的要求。在设定板材密度一定的情况下,板材性能随厚度的增加而先增加后减小。     

漫谈高浓度甲醛在刨花板用胶黏剂生产中的应用

分析了高浓度甲醛溶液在刨花板用胶生产中的应用,探讨了该生产技术没有得到广泛应用的主要原因,并提出了高浓度甲醛供应问题的解决办法。