钛酸钾晶须增强聚醚醚酮复合材料的制备与性能研究

发布时间：2018-01-19 22:14

  本文关键词： PEEK PTW PTFE 力学性能 摩擦学性能　出处：《湖南工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：本论文研究了用六钛酸钾晶须(PTW)和聚四氟乙烯(PTFE)填充改性聚醚醚酮(PEEK),制得PTW/PEEK和PTFE/PTW/PEEK复合材料,并探讨了复合材料的力学及摩擦学性能。先用偶联剂对六钛酸钾晶须进行活化处理,筛选确定了合适的偶联剂类型并确定了其最佳用量,用经过活化处理后的PTW填充改性PEEK制得复合材料,并通过注塑成型制备检测试样。采用MM200摩擦磨损试验机和45#钢环配副研究了PTW质量分数对复合材料摩擦学性能的影响以及PTW和PTFE对复合材料的协同作用效果。利用扫描电子显微镜观察分析了复合材料断口表面和磨损表面形貌,并分析了磨损机理。研究结果表明,钛酸酯偶联剂TM38-S适合用于活化处理PTW,且当TM38-S用量为PTW质量分数的1%时,活化效果最好。对PTW/PEEK复合材料注塑成型条件研究表明,注塑温度及模具温度对复合材料的力学性能影响极大:随着注塑温度的升高,制品的拉伸强度和弯曲强度呈现先升后降的趋势,当注塑温度过高时,PEEK的热分解现象加剧,在注塑制品中容易生成大的球晶,从而使制品易碎,力学性能降低;随着模具温度的升高,制品的拉伸强度和弯曲强度也随之升高,但是当模具温度过高时,制品的内部会产生气孔,容易产生产品塌陷现象。故控制模具温度为(180±10)℃,在此温度下,熔体有较好的充模特性,材料的结晶度高,并且无再结晶峰,力学性能优良;另外通过对PTW/PEEK制品进行退火处理后,PTW/PEEK制品的力学性能进一步得到提高。在注塑温度由前到后依次为390℃、380℃、365℃,模具温度为180℃,对PTW/PEEK制品进行注塑成型后,并在退火处理条件为200℃,1h下对试样进行退火后,所制得的复合材料的综合性能最优。在干摩擦条件下,填充PTW可明显降低PEEK基复合材料的摩擦系数,随着PTW含量增加,PTW/PEEK复合材料摩擦系数先降低后略有升高,复合材料的磨损量也随PTW含量的增加而降低,当PTW含量为15%时耐磨性能最佳。PTFE以一定的质量比添加进PTW/PEEK复合材料时可降低复合材料摩擦系数,也使复合材料的耐磨性显著提高,且随着PTFE质量分数增加,PTFE/PTW/PEEK复合材料的耐磨性能随之提高,但复合材料的力学性能降低,这是由于组分间相容性不佳造成的。分析认为,PTW晶须提高了复合材料的表面承载能力,摩擦过程中减少摩擦副表面粘着和剥层,阻止基体树脂的热塑性变形,同时PTFE的优先粘着转移使得PTW/PTFE/PEEK复合材料在对偶表面形成的转移膜最薄,连续性与均匀性最好,两者协同有效提高复合材料的摩擦学性能。综合考虑复合材料耐磨性能、力学性能与配方成本,本文研究得出复合材料中PTW:PTFE:PEEK最佳质量配比为15:8:77。
[Abstract]:In this paper, the modified polyether ether ketone (PEEK) was filled with potassium hexatitanate (PTW) and PTFEs (PTFEs). PTW/PEEK and PTFE/PTW/PEEK composites were prepared, and the mechanical and tribological properties of the composites were discussed. Firstly, potassium hexatitanate whiskers were activated by coupling agent. The suitable type of coupling agent was selected and the optimum dosage was determined. The composite material was prepared by filling the modified PEEK with activated PTW. The effect of PTW mass fraction on the tribological properties of composites and the effects of PTW and PTFE on the tribological properties of composites were studied by MM200 friction and wear test machine and 4 steel ring matching pair. Scanning electron microscope (SEM) was used to observe and analyze the fracture surface and wear surface morphology of the composites. The wear mechanism was analyzed. The results showed that the titanate coupling agent TM38-S was suitable for the activation treatment of PTW, and when the amount of TM38-S was 1% of PTW. The research on injection molding conditions of PTW/PEEK composite shows that injection temperature and mold temperature have great influence on the mechanical properties of the composite: with the increase of injection temperature. The tensile strength and bending strength of the products increased first and then decreased. When the injection temperature was too high, the thermal decomposition of peek was intensified, and the large spherulites were easily formed in the injection molding products, thus making the products fragile. Reduction of mechanical properties; With the increase of mold temperature, the tensile strength and bending strength of the product also increase, but when the mold temperature is too high, the internal pores will be produced. It is easy to produce product collapse, so the mold temperature is controlled at 180 卤10 鈩，

本文编号：1445700