超微竹炭增强聚丙烯基复合材料性能研究

发布时间：2018-09-07 19:03

【摘要】：为提高聚丙烯基复合材料的性能,利用毛竹及其加工剩余物制备的超微竹炭(UFBC)作为增强材料引入聚丙烯(PP)基体,制备复合材料。探索了不同成型工艺、不同超微竹炭添加量及超微竹炭粒径对PP/UFBC复合材料力学性能、耐湿性能及热特性等性能的影响;通过表征聚丙烯与超微竹炭二元体系结构,揭示其界面结合与强化机理;同时探讨了竹颗粒(BP)、超微竹炭与聚丙烯三元复合材料的制备、结构与性能,明确三元复合材料中三元质量配比对材料性能的影响,表征三元体系结构,探明了超微竹炭与竹颗粒对聚丙烯基复合材料的协同增强效果。(1)采用超微竹炭增强聚丙烯基复合材料,对比研究不同成型工艺与超微竹炭添加量对PP/UFBC复合材料性能的影响。采用混炼挤出与注塑成型制备复合材料,在超微竹炭添加量为30%时材料的拉伸强度达到较大值26 MPa;在超微竹炭添加量为40%时材料的拉伸模量达到较大值450 MPa。熔融混炼与热压成型法制备PP/UFBC复合材料,超微竹炭添加量为40%-50%时,材料拉伸强度较优。在超微竹炭添加量为30%时材料的拉伸模量达到较大值370 MPa。注塑成型工艺制备的材料拉伸性能与耐湿性能较热压成型工艺制备的材料更优,在超微竹炭添加量为20%时,注塑成型复合材料的拉伸强度较热压成型材料提高了 5MPa;注塑成型较适于超微竹炭含量较低复合材料的制备,热压成型较适于超微竹炭含量较高的复合材料制备。两种不同成型工艺制备复合材料时,超微竹炭的添加对材料耐湿性能的影响不明显;超微竹炭能较好地提升材料的结晶温度和熔融温度,改善了材料的加工性和耐热性,但不同工艺对材料热特性的影响并不明显。(2)采用混炼挤出与注塑成型工艺制备了两种粒度超微竹炭与聚丙烯复合材料,两种不同粒度超微竹炭对聚丙烯基复合材料的拉伸性能均有较好的增强作用。在粒度1超微竹炭含量为30%时材料的结晶温度达到较大值120.5℃,较聚丙烯提高了 10.4℃。随着粒度2超微竹炭添加量的增大,复合材料的拉伸强度与拉伸模量不断增大,断裂伸长率不断减小,超微竹炭添加量为40%时,复合材料的拉伸强度达到了 33 MPa,拉伸模量达到了500 MPa;对比两种粒度超微竹炭对聚丙烯基复合材料性能的影响,粒度2超微竹炭对复合材料力学性能、耐湿性能、热特性的增强作用均要优于粒度1超微竹炭,较细粒度的超微竹炭对复合材料的增强效果较优。PP/UFBC复合材料的吸湿率均小于0.1%,材料的耐湿性能较优,超微竹炭的加入对复合材料耐湿性能的影响不明显。超微竹炭的添加对材料的结晶温度和熔融温度均有较大的提升作用;微观形态分析表明,超微竹炭在基体中分散均匀,两者界面结合良好。(3)同时引入竹颗粒、超微竹炭作为增强体与聚丙烯基体制备了三元复合材料。超微竹炭与竹颗粒通过促进分散性与形成稳定的三元晶核结构对三元复合材料的力学性能、热特性等有较优的协同增强作用,达到了较好的增强效果。在PP/BP/UFBC质量配比为70/25/5时,复合材料的拉伸强度达到较大值30 MPa,较纯聚丙烯材料提高了 30%;在PP/BP/UFBC质量配比为70/20/10时,三元复合材料的拉伸模量达到较大值为460 MPa;密度达到较小值0.96 g/cm3;耐湿性能达到较优值,吸湿率较小为0.05%;熔融温度也达到较大值166.6℃,较纯聚丙烯材料提高了 5.9℃。PP/BP/UFBC三元复合材料的力学性能、热特性等较纯聚丙烯与二元复合材料均有所提升。PP/BP/UFBC质量配比为70/20/10时,三元复合材料的拉伸模量较PP/BP(70/30)、PP/UFBC(70/30)二元复合材料和聚丙烯分别提高了 35%、24%和 109%。
[Abstract]:In order to improve the properties of polypropylene matrix composites, ultrafine bamboo charcoal (UFBC) was used as reinforcing material to introduce into polypropylene (PP) matrix to prepare composites. The interfacial bonding and strengthening mechanism was revealed by characterizing the binary structure of polypropylene and superfine bamboo charcoal, and the preparation, structure and properties of bamboo particle (BP), superfine bamboo charcoal and polypropylene ternary composites were discussed. The synergistic reinforcing effect of superfine bamboo charcoal and bamboo particles on PP matrix composites was investigated. (1) The effects of different molding processes and the amount of superfine bamboo charcoal on the properties of PP/UFBC composites were compared. The composites were prepared by mixing extrusion and injection molding. The tensile strength of PP/UFBC composites was 26 MPa when the carbon content was 30% and 450 MPa when the superfine bamboo carbon content was 40%. The tensile strength of PP/UFBC composites was better when the superfine bamboo carbon content was 40%-50%. The tensile modulus is 370 MPa. The tensile properties and moisture resistance of the materials prepared by injection molding process are better than those prepared by hot-pressing process. The tensile strength of the composites prepared by injection molding is 5 MPa higher than that of hot-pressing materials when the content of Ultra-micro bamboo charcoal is 20%. The addition of superfine bamboo charcoal has no obvious effect on the moisture resistance of the composites. The superfine bamboo charcoal can improve the crystallization temperature and melting temperature of the materials, and improve the processability and heat resistance of the materials. (2) Two kinds of ultra-fine bamboo charcoal and polypropylene composites were prepared by mixing extrusion and injection molding, and the two kinds of ultra-fine bamboo charcoal had better reinforcing effect on the tensile properties of polypropylene matrix composites. When the content of ultra-fine bamboo charcoal was 30%, the composites were prepared by mixing extrusion and injection molding. The tensile strength and modulus of the composites increased with the increase of the addition amount of 2-ultrafine bamboo charcoal, and the elongation at break decreased. When the addition amount of 40% ultrafine bamboo charcoal was added, the tensile strength of the composites reached 33 MPa and the tensile modulus reached 500 MPa. Comparing the effect of two kinds of ultrafine bamboo charcoal on the properties of polypropylene matrix composites, the mechanical properties, moisture resistance and thermal properties of the composites reinforced by ultrafine bamboo charcoal with particle size 2 are better than those by ultrafine bamboo charcoal with particle size 1, and the reinforcing effect of the composites reinforced by ultrafine bamboo charcoal is better. The addition of ultrafine bamboo charcoal can greatly improve the crystallization temperature and melting temperature of the composites. The microscopic morphology analysis shows that ultrafine bamboo charcoal disperses evenly in the matrix, and the interface between the two is well bonded. (3) At the same time, the introduction of bamboo particles, super-fine bamboo charcoal. Micro-bamboo charcoal was used as reinforcement and polypropylene matrix to prepare ternary composites. The micro-bamboo charcoal and bamboo particles had better synergistic reinforcing effect on the mechanical properties and thermal properties of the Ternary Composites by promoting dispersion and forming stable ternary nucleus structure. The mass ratio of PP/BP/UFBC was 70/25/5. When the mass ratio of PP/BP/UFBC is 70/20/10, the tensile modulus of the ternary composites is 460 MPa, the density is 0.96 g/cm 3, the moisture resistance is better, the moisture absorption is less than 0.05%, and the melting temperature is higher. The mechanical properties and thermal properties of PP/BP/UFBC ternary composites were improved compared with those of pure PP and binary composites. The tensile modulus of PP/BP/UFBC ternary composites was higher than that of PP/BP(70/30), PP/UFBC(70/30) binary composites and polypropylene respectively when the mass ratio of PP/BP/UFBC was 70/20/10. It's 35%, 24% and 109%..
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332

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