熔体纺丝法制备UHMWPE纤维及其单丝滤布的性能研究
发布时间：2019-01-27 18:56
【摘要】：超高分子量聚乙烯纤维由于超高的分子量、高缠结度的分子链,以及经过高倍率拉伸产生具有高取向度、高结晶度的伸直链结构,具有极佳的力学性能、化学稳定性、耐磨、低表面性能,是作为高性能滤布的理想材料,这是其它纤维无法比拟的。本课题选用中等分子量MP、小分子物质LP为改性剂,采用熔体纺丝法制备UHMWPE纤维,将制备的纤维织造成2/2斜纹组织单丝滤布。本课题研究了改性剂对UHMWPE原料的改性机理;探究超倍率拉伸的工艺参数(拉伸温度、拉伸倍率、停留时间)对UHMWPE纤维性能的影响,为下一步工厂大规模生产制备UHMWPE滤用纤维提供经验参考;探究热定型工艺参数(定型温度、定型时间、定型张力)对UHMWPE单丝滤布的机械性能、透气性能、尺寸稳定性、鼓泡孔径等性能的影响,建立滤布性能与热定型工艺各因子之间的经验关系;筛选出最佳热定型工艺条件。通过分析,改性剂MP、LP协同改变UHMWPE的流动性和可纺性,LP分子链使UHMWPE晶区片晶解缠,而MP则是降低非晶区的大分子链间的缠结点密度。但添加量达到20份时,会造成纤维的性能下降。在适宜的油浴温度、拉伸倍率、停留时间等条件下,纤维大分子链会沿应力方向的取向,其力学性能会得到极大提高。但长时间在过高的温度会使大分子链热解、产生无效滑移,过高的拉伸倍率使纤维结构的缺陷度增大,一级拉伸最佳温度约为90°℃、最佳倍率约为25倍。在合适的定型温度、时间、经向张力条件下,UHMWPE滤布纤维内的结晶度、结晶完整性会得到提高,滤布的结构变得更加的规整、致密、稳定,孔径也更加均匀。而长时间高温下的定型会使滤布纤维分子链热解、重结晶,加速了滤布的老化,致使滤布的缺陷增大、性能下降。UHMWPE单丝滤布的最佳热定型温度约为100℃,定型时间约为90s,经向张力约为100KN。熔体纺丝法制备出的UHMWPE纤维,完全能满足制作单丝滤布的要求。
[Abstract]:UHMWPE fibers have excellent mechanical properties, chemical stability and wear resistance due to their ultra-high molecular weight, high entanglement molecular chain, and elongation chain structure with high orientation and high crystallinity after drawing at high rate. Low surface performance is an ideal material for high performance filter cloth, which can not be compared with other fibers. In this paper, the medium molecular weight MP, small molecular material LP was selected as the modifier, and the UHMWPE fiber was prepared by melt spinning method. The prepared fiber was woven to make 2 / 2 twill tissue monofilament filter cloth. In this paper, the modification mechanism of modifier on UHMWPE raw material was studied. The effects of the process parameters (drawing temperature, drawing ratio, residence time) on the properties of UHMWPE fiber were investigated, which provided the experience reference for large-scale production of UHMWPE filter fiber in the next step. To explore the effects of heat setting process parameters (setting temperature, setting time, setting tension) on the mechanical properties, air permeability, dimensional stability, bubble diameter and other properties of UHMWPE monofilament filter cloth. The empirical relationship between filter cloth performance and various factors of heat setting process is established. The optimum process conditions of heat setting were screened out. Through analysis, the modifier MP,LP co-changed the fluidity and spinnability of UHMWPE. The LP molecular chain unentrapped the UHMWPE wafers, while MP reduced the entanglement point density between the macromolecular chains of amorphous region. However, the addition of 20 phr will result in the degradation of the properties of the fiber. Under the suitable conditions of oil bath temperature, tensile ratio and residence time, the fiber macromolecular chain will be oriented along the stress direction, and its mechanical properties will be greatly improved. However, when the temperature is too high for a long time, the chain will be pyrolyzed, resulting in invalid slippage. The defect degree of the fiber structure will be increased when the drawing ratio is too high. The optimum temperature of the first order drawing is about 90 掳鈩，
本文编号：2416585
[Abstract]:UHMWPE fibers have excellent mechanical properties, chemical stability and wear resistance due to their ultra-high molecular weight, high entanglement molecular chain, and elongation chain structure with high orientation and high crystallinity after drawing at high rate. Low surface performance is an ideal material for high performance filter cloth, which can not be compared with other fibers. In this paper, the medium molecular weight MP, small molecular material LP was selected as the modifier, and the UHMWPE fiber was prepared by melt spinning method. The prepared fiber was woven to make 2 / 2 twill tissue monofilament filter cloth. In this paper, the modification mechanism of modifier on UHMWPE raw material was studied. The effects of the process parameters (drawing temperature, drawing ratio, residence time) on the properties of UHMWPE fiber were investigated, which provided the experience reference for large-scale production of UHMWPE filter fiber in the next step. To explore the effects of heat setting process parameters (setting temperature, setting time, setting tension) on the mechanical properties, air permeability, dimensional stability, bubble diameter and other properties of UHMWPE monofilament filter cloth. The empirical relationship between filter cloth performance and various factors of heat setting process is established. The optimum process conditions of heat setting were screened out. Through analysis, the modifier MP,LP co-changed the fluidity and spinnability of UHMWPE. The LP molecular chain unentrapped the UHMWPE wafers, while MP reduced the entanglement point density between the macromolecular chains of amorphous region. However, the addition of 20 phr will result in the degradation of the properties of the fiber. Under the suitable conditions of oil bath temperature, tensile ratio and residence time, the fiber macromolecular chain will be oriented along the stress direction, and its mechanical properties will be greatly improved. However, when the temperature is too high for a long time, the chain will be pyrolyzed, resulting in invalid slippage. The defect degree of the fiber structure will be increased when the drawing ratio is too high. The optimum temperature of the first order drawing is about 90 掳鈩，
本文编号：2416585
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