木橡塑三元复合材料的制备及性能研究

发布时间：2018-04-03 00:25

本文选题：废旧橡胶　切入点：复合材料　出处：《南京林业大学》2015年硕士论文

【摘要】：利用废旧橡胶粉、塑料(HDPE)和木粉制备木橡塑三元复合材料(WRPC)是木质多元复合的新探索,在该体系中,木质材料作为增强相,起到“骨架”作用,橡胶则起到弹性增强作用,塑料基体充当复合材料中的“胶黏剂”成分,将三相材料结合在一起。本文采用挤出成型方法制备三元复合材料,系统探究了木橡塑三元复合材料的原料配比、界面改性及橡胶增韧效果评价等问题,为制备木橡塑三元复合材料提供理论基础。研究结果表明:1、三种原料之间的配比比例对材料力学性能影响显著。橡胶的加入,改善了材料的冲击强度,但削弱了材料的拉伸强度和弯曲强度。木粉与废旧橡胶粉在力学性能上具有明显的互补性。三元复合体系中,木粉用量宜在30%以上,且塑料/橡胶不小于4/6方能获得一定的强度,同时保证成型。2、研究橡胶的增韧效果时发现,将废旧橡胶粉添加到纯木塑复合材料中,在原料表面未经处理情况下,橡胶添加量为10%时,复合材料表现出较好的压缩回弹性,而冲击强度随橡胶用量在0-15%范围内的增加而增加,同时,橡胶用量为10%组,复合材料的阻尼性能最优,阻尼比较未添加橡胶组增大了67%(时域法)。3、采用马来酸酐接枝聚乙烯(MAPE)与硅烷(Si69)偶联剂改善复合材料的界面结合特性。MAPE添加量(占木粉)为3%、5%和8%,Si69添加量(占橡胶粉)为0.5%、1%、3%、5%。红外分析表明,经不同含量硅烷偶联剂处理后的废旧橡胶粉,其表面的羟基基团数量增多,极性增强。两种偶联剂对复合体系的流变特性的影响呈两极化趋势,5%MAPE用量下材料的剪切应力和表观黏度值最小,加工性能最优,硅烷偶联剂的用量则在3%时为最佳。两种偶联剂的配合使用可以达到较好的协同作用,提高复合材料的力学性能。MAPE用量越高,材料力学性能越好。Si69用量的选取宜与MAPE间形成良好配合,较低MAPE用量下,复合材料的力学性能随Si69添加量的增大而增大,而当MAPE用量较高时,综合考虑材料的力学性能与胶粉表面处理的方便性,Si69的用量以0.5%为宜。4、氙灯老化试验结果显示,在0-480h的老化时间内,复合材料的抗弯强度呈现先降后增最后再降的过程,橡胶改变了复合材料的老化过程,但不加速老化。偶联剂MAPE、Si69均能提高复合材料耐老化性,主要体现在老化后期材料强度的保持上。5、采用热重分析法(TGA)研究各组分材料及WPC和WRPC的热解动力学特性发现,WRPC的热解出现两个显著的失重区(230℃~380℃和430℃~580℃),分别对应木粉/废旧橡胶和HDPE的热降解。采用Flynn-Wall-Ozawa模型计算出木粉、废旧橡胶粉和HDPE热解过程平均活化能值分别为179.2KJ/mol、243.8KJ/mol和246.8KJ/mol,WPC为239.3KJ/mol,而WRPC活化能值比WPC低(200.3 KJ/mol~208.4 KJ/mol)。活化能的变化表明木、橡、塑三种原料在复合材料的热解过程中具有协同效应,废旧橡胶的掺入对复合材料的热降解特性发挥了显著的调控作用。6、采用锥形量热仪测定复合材料燃烧过程中的点燃时间(TTI)、热释放速率(HRR)、总热释放量(THR)、质量损失速率(MLR)、发烟总量(TSP)以及CO、CO2的释放速率等燃烧降解性能指标。结果表明:与木塑复合材料相比,WRPC材料的点燃时间缩短,CO2释放量有所减少,而热释放速率、总热释放量及发烟总量均有所提高。因此,废旧的木橡塑复合材料可作为优良的燃料予以回收利用,废旧橡胶则能发挥助燃作用。
[Abstract]:The use of waste rubber powder (HDPE), plastic and wood powder three yuan composite wood plastic (WRPC) is a new exploration of wood complex, in this system, the wood material as reinforcing phase, play a "skeleton", plays the enhancement effect of elastic rubber, plastic matrix composites when filling the "adhesive" component, three-phase materials together. The preparation of three element composite material forming method for extrusion system on the ratio of raw materials three Yuan wood rubber composite, interfacial modification was evaluated and the effect of rubber toughening and other issues, to provide a theoretical basis for the preparation of the three element composite wood plastic. Results 1, show that the effect of three kinds of raw materials between the proportion of material mechanical properties remarkably. The addition of rubber to improve the impact strength of the material, but weaken the tensile strength and the flexural strength of the composites. The wood powder and waste rubber powder on the mechanical properties Has the obvious complementary. The three element composite system, the content of wood powder is over 30%, and the plastic / rubber is not less than 4/6 in order to obtain a certain strength, at the same time ensure molding.2, found that the research of rubber toughening effect, adding rubber powder to pure wood plastic composite materials, raw materials in the surface the case, rubber dosage is 10%, the composite exhibits better compression resilience, while the impact strength with the rubber content in the range of 0-15% increases, at the same time, the amount of rubber into 10% groups, the optimal damping properties of composite materials, the damping is not added Rubber Group increased 67% (time domain method.3), using maleic anhydride grafted polyethylene (MAPE) and silane coupling agent (Si69) to improve the interfacial binding characteristics of the amount of.MAPE (for wood powder) was 3%, 5% and 8%, adding Si69 (for rubber powder) was 0.5%, 1%, 3%, 5%. infrared analysis showed that the Waste rubber powder with the content of silane coupling agent treatment, the surface hydroxyl group number and polarity enhancement. Influence of rheological properties of two kinds of coupling agents on the composite system of the trend was polarized, the amount of 5%MAPE material under shear stress and apparent viscosity of the minimum processing of optimal, silane coupling agent the amount in 3% was the best. Two kinds of coupling agents can achieve good synergistic effect, improve the mechanical properties of composite materials.MAPE was higher, the better mechanical properties of the material selection should form a good amount of.Si69 with MAPE, the lower the amount of MAPE, the mechanical properties of composite materials and the increase of the amount of with the increase of Si69, but when the content of MAPE is high, considering the mechanical properties of materials and powder surface treatment convenience, the dosage of Si69 was suitable for 0.5%.4 xenon test results showed that in the 0-480h age In between, the bending strength of the composites showed increased after the first drop finally lower, rubber changed the aging process of composite materials, but not accelerated aging. Coupling agent MAPE, Si69 can improve the aging resistance of composite materials, mainly reflected in the strength of materials keep on aging late.5 by thermogravimetric analysis (TGA) found that the pyrolysis kinetics characteristics research materials and components WPC and WRPC, WRPC showed two significant weight loss of the pyrolysis zone (230 DEG ~380 DEG and 430 DEG ~580 DEG), corresponding to thermal degradation of wood powder / rubber and HDPE. Using Flynn-Wall-Ozawa model to calculate the energy value of wood powder, respectively. The average 179.2KJ/mol activated waste rubber powder and HDPE pyrolysis process, 243.8KJ/mol and 246.8KJ/mol, WPC 239.3KJ/mol, and the WRPC value of the activation energy is lower than that of WPC (200.3 KJ/mol~208.4 KJ/mol). The activation energy of the wooden table changes, rubber, plastic raw materials in three kinds of composite heat The synergistic effect of the solution process, the incorporation of waste rubber thermal degradation characteristics of composite materials play a significant regulatory role of.6, the determination of ignition time in combustion process of composite materials by cone calorimeter (TTI), heat release rate (HRR), total heat release (THR), mass loss rate (MLR), smoke volume (TSP) and CO, the release rate of CO2 combustion performance degradation. The results showed that: compared with wood plastic composite material WRPC, ignition time is shortened, the release amount of CO2 decreased, and the heat release rate, total heat release and the total smoke were improved. Therefore, wood waste rubber plastic composite material can be used as excellent fuel to recycling, waste rubber can play the combustion effect.

【学位授予单位】：南京林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

【参考文献】