超高分子量聚乙烯的加工与应用

超高分子量聚乙烯(UHMWPE)是指分子量在100万～500万以上的线型结构聚乙烯,由于其巨大的分子量,使之具有一些普通PE、其它工程塑料和一些金属材料所不及的优异的综合性能。本文阐述了超高分子量聚乙烯的基本性能,介绍了主要的成型加工方法及其在各方面的应用情况。     

超高分子量聚乙烯(UHMWPE)的性能、成型加工及其应用

<正> 超高分子量聚乙烯(UHMWPE)的分子结构和普通高密度聚乙烯完全相同,但普通高密度聚乙烯的分子量较低,约在(5～30)×10~4的范围内,而超高分子量聚乙烯则具有10~6以上那样极大的分子量,因此具有普通高密度聚乙烯及其它一些工     

超高分子量聚乙烯发展前途佳

超高分子量聚乙烯(UHMPWE)是一种新型热塑性工程塑料,它的分子结构和普通聚乙烯完全相同,普通聚乙烯的分子量一般在4万～12万,而UHMWPE可达到100万～400万。随着分子量的大幅度升高,树脂的某些性能会发生突变,比如耐磨性佳、抗冲击性强,而且在低温时抗冲击仍较高,自润滑性好等。UHMWPE可以取代碳钢、不锈钢、青铜等,用于纺织、造纸、食品机械、运输、陶瓷、煤炭等领域。目前,世界上UHMWPE年生产能力为8万t。我国UHMWPE年生产能力为1万t。     

对超高分子量聚乙烯的研究

超高分子量聚乙烯(UHMW PE)是指分子量在100万～500万以上的线型结构聚乙烯,由于其巨大的分子量,使之具有一些普通PE、其它工程塑料和一些金属材料所不及的优异的综合性能。本文阐述了超高分子量聚乙烯的基本性能,介绍了主要的成型加工方法及其在各方面的应用情况。     

超高分子量聚乙烯膜的改性方法及其在医用材料中的应用

聚乙烯(PE)为热塑性树脂,由乙烯聚合制备,已经成为产量最大的塑料品种,且聚乙烯相关塑料、膜材的产品产量逐年增加。超高分子量聚乙烯(UHMWPE)是典型的生物材料,具有优异综合性能且具有良好热塑性。超高分子量聚乙烯(UHMWPE)产品及膜材质量优良、价格相对便宜且用途十分广泛,但UHMWPE也具有一些缺陷与不足,比如表面硬度较低、弯曲强度较差等,这些缺陷和不足在一定程度上限制了UHMWPE的实际应用。因此,应对UHMWPE进行表面改性,以提高UHMWPE的性能。对UHMWPE的常用改性方法进行研究,包括物理改性、化学改性、光接枝改性以及表面活性剂改性等,然后分析了UHMWPE在医学材料中的具体应用。     

应用超高分子量聚乙烯,解决落煤斗堵煤难题

超高分子量聚乙烯是一种新型的高分子聚合物 ,它所具有的一些优良特性使得用其制成的衬板在湿煤和粘煤经过时不会堵煤 ,而且耐磨性和抗冲击能力极好。本文主要介绍超高分子量聚乙烯的性能、特点以及用它制成的衬板在解决落煤斗堵煤这一难题中的作用。1　超高分子量聚乙烯性能超高分子量聚乙烯 (ＵＨＭＷＰＥ)是国际上最新的工程塑料 ,其分子结构和普通聚乙烯 (ＰＥ)相同。所不同的是普通ＰＥ分子量较低 (几万至几十万 ) ,而ＵＨＭＷＰＥ的分子量一般均超过 10 0万 ,巨大的分子量使其具有一些普通ＰＥ及其他工程塑料所没有的独特性能。1 1　…     

UHMWPE的近熔点挤出技术及制品性能与应用

概述超高分子量聚乙烯(UHMWPE)材料改性和加工技术的进展,提出了近熔点挤出的理念,着重介绍了江苏联冠科技发展有限公司推出的分子量在250万以上的UHMWPE挤出制品的生产新技术及其制品性能检测结果,展望了UHMWPE管材的应用领域。     

超高分子量聚乙烯纤维/有机玻璃复合材料摩擦磨损性能研究

用真空浸渍法成功制备出了超高分子量聚乙烯纤维／有机玻璃(UHMWPE／PMMA)复合材料，并对基体材料PMMA，单向超高分子量聚乙烯纤雏／有机玻璃复合材料以及三维编织超高分子量聚乙烯纤维／有机玻璃(即UHMWPE3D／PMMA)复合材料的摩擦磨损性能进行了研究。实验证明UHMWPE／PMMA复合材料具有优良的摩擦磨损性能。经过纤维增强的复合材料的摩擦磨损性能优于基体材料，三维编织纤维增强的复合材料其磨损远小于单向纤维增强的复合材料，但其摩擦系数没有显著变化。     

凝胶纺丝法制备超高分子量聚乙烯/高分子量聚乙烯纤维延伸性能的研究

用凝胶纺丝法制备了超高分子量聚乙烯(UHMWPE)/高分子量聚乙烯(HDPE)纤维,探讨了添加不同种类高分子量聚乙烯对凝胶初生纤维在后续延伸过程中延伸性能的影响。结果表明在固定制备条件时,当超高分子量聚乙烯(UHMWPE)/高分子量聚乙烯(HDPE)的质量比在最适当质量比时,高分子量聚乙烯的分子量为1.5～2.0×104时,所制备的凝胶初生纤维的可延伸比达最大值。     

超高分子量聚乙烯的特性加工方法及其应用

1 前言超高分子量聚乙烯(UHMWPE)是德国Hoechst公司于1958年作为商品最早在世界上出售的。继该公司之后,美国Hercules公司、日本三井石油化学工业股份有限公司相继从出售树脂开始,逐步发展UHMWPE塑料制品生产,并着力开拓应用领域。超高分子量聚乙烯的分子结构和普通高密度聚     

超高分子量聚乙烯材料的研究进展

超高分子量聚乙烯（UHMWPE）是高性能聚烯烃材料的典型代表,稳定的线性长链结构使其具有高强度、耐冲击、耐磨损、自润滑、耐化学腐蚀、耐低温等诸多优异性能。近年,UHMWPE加工、改性技术日益扩展、优化,形成了多种多样的UHMWPE制品,广泛应用于军民各项领域。本文综述了UHMWPE在催化聚合、纤维、膜、管材、板材及型材等方面的最新进展,重点介绍在各领域应用、加工、改性等方面的研究成果和发展趋势。     

Study on molding process of UHMWPE microporous filter materials

A method called loose sintering was first introduced to prepare ultrahigh‐molecular weight polyethylene (UHMWPE) microporous materials. The pore size was predicted by the face‐centered cubic structure model while considering the particles' arrangement and melt. The results showed that the experimental pore diameter was close to that calculated by the present model. The effects of UHMWPE molecular weight, particle diameter, packing density, sintering temperature, and sintering time on pore size, compressive strength, pore diameter distribution, and density were presented. The morphology of micropore and the uniformity of pore distribution were analyzed by scanning electron microscopy and fractal geometry. The results showed that average pore diameter and porosity both increased with the UHMWPE particle diameter while decreased with compressive strength and bulk density. Sintering temperature and sintering time determined whether the heat was redundant to melt the particles. They also determined the pore size and the uniformity. UHMWPE microporous materials could be successfully prepared with suitable processing conditions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Exploring the entangled state and molecular weight of UHMWPE on the microstructure and mechanical properties of HDPE/UHMWPE blends

Three types of ultra-high molecular weight polyethylene (UHMWPE) with different entangled state and molecular weight were blended with high-density polyethylene (HDPE) matrix by melt blending. Rheology, 2D-SAXS, 2D-WAXD, DSC, and mechanical tests were used to study the evolution and difference of microstructure and mechanical properties of the blends. The addition of weakly entangled UHMWPE enhanced the chain diffusion and chain orientation ability under a specific flow field. Thus, the rheological properties and mechanical properties of the blends were improved with the mix of weakly entangled UHMWPE. The mechanical properties enhancement effect of HDPE/UHMWPE blends with weakly entangled UHMWPE was owing to the shish-kebab structure formed in the injection molding process. The molecular chains of UHMWPE with a low degree of entanglement and high molecular weight increased the lamella size and crystallinity of the blends during processing. This leads to the formation of more oriented shish structures and more kebab lamella. Besides, the molecular chains of weakly entangled UHMWPE were better interlocked and intertwined with other polyethylene chains in the amorphous region, acting as the tie molecules, significantly improving the impact resistance.     

Electrical properties of polyethylene and carbon black particle blends prepared by gelation/crystallization from solution

Composite materials based on low molecular weight polyethylene (LMWPE), ultra-high molecular weight polyethylene (UHMWPE) and carbon black (CB) particles were prepared by gelation/crystallization from solution. The positive temperature coefficient (PTC) intensity for the 90/10 (LMWPE/UHMWPE) composition exceeded five orders of magnitude for the specimens heat-treated at a suitable temperature, which was almost equal to that observed with LMWPE-CB blends prepared by a kneading method. In comparison with LMWPE-CB blends, much promoted reproducibility of PTC effect and inhibition of the negative temperature coefficient (NTC) effect were achieved.     

同心双螺杆成型纯超高分子量聚乙烯管材新方法

介绍了一种采用同心双螺杆挤出机实现流动性差纯UHMWPE管材连续挤出成型的新技术;该技术解决了流动性差这类高分子材料管材螺杆挤出成型的技术难题.     

抗氧剂在UHMWPE溶解过程中的作用

采用相对分子质量比较了抗氧剂1010和Ciba Irganox B 225混合抗氧剂在超高相对分子质量聚乙烯(UHMWPE)溶解过程中的抗降解作用。结果表明:在UHMWPE溶解过程中,随着温度的升高,加热时间的增长,UHMWPE的相对分子质量有明显的下降;而抗氧剂能有效抑制UHMWPE的降解,其用量增加,抑制 UHMWPE降解的作用也随之增大;当加热110 min,温度升至180℃时,加入质量分数为2％的混合抗氧剂, UHMWPE的相对分子质量下降33．9％,而未加混合抗氧剂时,UHMWPE的相对分子质量下降70．2％。相同用量时,混合抗氧剂效果比抗氧剂1010好。     

超高相对分子质量聚乙烯纤维及其应用

本文介绍了超高相对分子质量聚乙烯(UHMWPE)纤维的制备方法及其发展现状，并简要概述了该纤维的结构、性能、改性方法及其在各领域中的应用。     

Extrusion processing of ultra-high molecular weight polyethylene; a new method for the production of high performance structures

We report preliminary findings relating to a method of processing ultra-high molecular weight polyethylene (UHMWPE) in order to obtain extrusions that possess significant molecular orientation and improved mechanical properties. We also show that the method can be used to produce oriented extrusions of composite materials consisting of glass or carbon fibres in a matrix of UHMWPE.     

Effect of gamma ray irradiation on processability and properties of ultra high molecular weight polyethylene

Ultra high molecular weight polyethylene (UHMWPE) has been widely used in many fields due to its outstanding properties. However, it is virtually impossible to be processed by the conventional method due to its high molecular weight and very tight chain entanglement. To solve this problem, a new method was proposed in this article. Gamma ray irradiation was adopted to cause the oxidation degradation of UHMWPE. The degraded products which generated in situ and dispersed in UHMWPE evenly were utilized as self‐lubricant and heat transfer intermediary. These low molecular weight fractions thus could improve the processability of UHMWPE. The effects of irradiation dose on the structure and properties of UHMWPE were studied by fourier transform infrared (FTIR) spectroscopy, gel content measurement, wide angle x‐ray diffraction (WAXD), Haake torque rheometer, mechanical properties measurements and sliding wear tests. The experimental results showed that gamma ray irradiation caused oxidation degradation of UHMWPE. Under appropriate irradiation condition, the processability of UHMWPE could be improved substantially while most of its excellent properties could be kept. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Short‐time fabrication of well‐mixed high‐density polyethylene/ultrahigh‐molecular‐weight polyethylene blends under elongational flow: morphology,mechanical properties and mechanism

As linear polyethylenes, ultrahigh‐molecular‐weight polyethylene (UHMWPE) and high‐density polyethylene (HDPE) have the same molecular structure, but the large difference in viscosity between them makes it difficult to obtain well‐mixed blends. An innovative eccentric rotor extruder (ERE) generating an elongational flow was used to prepare HDPE/UHMWPE blends within short processing times. Compared with the obvious two‐phase morphology of a sample from a twin‐screw extruder observed with a scanning electron microscope, few small UHMWPE particles were observed in the HDPE matrix for a sample from the ERE, indicating the good mixing on a molecular level of HDPE/UHMWPE blends achieved by the ERE during short processing times. The morphological changes of blends prepared using the ERE evidenced the good integration of HDPE and UHMWPE even though the UHMWPE content is up to 50 wt% in the blends. Moreover, all blends retained most of the intrinsic molecular weight. The good mixing was further confirmed from the thermal, crystallization and rheological behaviors determined using differential scanning calorimetry and dynamic rheological measurements. Importantly, the 50/50 blend presented improved mechanical properties, especially super‐impact strength of 151.9 kJ m^?2 with incomplete‐break fracture state. The strengthening and great toughening effects of UHMWPE on the blends were attributed to the addition of unwrapped UHMWPE long molecular chains. The effective disentanglement mechanism of UHMWPE chains under elongational flow was explained schematically by a non‐parallel three‐plate model. © 2019 Society of Chemical Industry