淤浆环管聚乙烯工艺反应器结皮原因分析及处理措施

随着社会的快速发展,聚乙烯的需求量越来越大,国内外聚乙烯生产装置也越来越多,淤浆法环管高密度聚乙烯装置成了主要生产高密度聚乙烯生产装置之一.在生产过程中,环管反应器经常出现结皮现象,严重影响了装置的正常运行.对淤浆法环管高密度聚乙烯工艺反应器结皮的原因进行分析,并提出了相应的处理措施.     

利用高密度聚乙烯装置生产线型低密度聚乙烯的相关研究

随着我国经济实力的飞速发展,对线型低密度聚乙烯的需求也有了很大的提升,相关部门必须对高密度聚乙烯装置生产线型低密度聚乙烯工艺给予足够的重视,并且加大对催化剂的研究力度。因此,主要对高密度聚乙烯装置生产线型低密度聚乙烯工艺进行了简要分析,阐述了相关催化系统,并且对生产工艺装置与主要生产流程进行了研究分析。     

大型聚乙烯工业装置质量指标的次优强跟踪滤波估计

针对大型聚乙烯工业装置质量指标实时估计的复杂性,基于乙烯聚合原理推导了大型聚乙烯工业装置质量指标实时预测模型,提出了一种次优强跟踪滤波器设计方法用于根据实验室分析数据反馈修正模型预测并实时估计质量指标。所提方法在大型聚乙烯工业装置上的应用结果证实了其有效性和可行性,为实现大型聚乙烯工业装置先进控制奠定了基础。     

中原聚乙烯生产现状及发展建议

介绍了中原乙烯聚乙烯装置的生产运行情况,并与国内外同类装置进行了比较,指出了聚乙烯装置的不足,对下一步发展提出了建议.     

天津石化生产聚乙烯三元共聚新品

<正>近日,天津石化聚乙烯装置首次成功生产出聚乙烯三元共聚新产品——TJZS-3100,标志着中国石化气相法聚乙烯生产技术取得了重大突破。多年以来,国内外线型聚乙烯装置一直采用乙烯、丁烯为主要加工原料来生产聚乙烯产品。此次生产的     

高压聚乙烯生产装置的使用及维护措施

聚乙烯生产过程中,应用高压聚乙烯生产装置,得到最佳的产品收率,依据生产工艺不同,采用的生产装置存在差异。对高压聚乙烯生产装置进行必要的维护保养,提高装置的运行效率,才能达到预期的聚乙烯产能,满足化工市场的需求。     

国内Unipol装置聚乙烯膜料的发展概况

介绍了国内Unipol气相聚乙烯装置概况.根据Unipol装置实际生产情况,从高密度聚乙烯(HDPE)膜料、线型低密度聚乙烯(LLDPE)膜料以及茂金属线型聚乙烯(mLLDPE)膜料三个方面做了详细阐述.最后结合国内禁塑令情况,对Unipol装置膜料未来的发展提出了几点建议.     

亚洲最大的氯磺化聚乙烯装置投产

2012年11月20日,随着吉林石化电石厂氯磺化聚乙烯装置产出氯磺化聚乙烯合格产品。这标志着亚洲最大的氯磺化聚乙烯装置经过增产改造,正式开车投产。这套装置是目前亚洲最大的生产该类产品的装置。装置始建于1968年,采用自主研发的技术。经过此次改造,装置目前设计年产已达3 000t。这套装置主要通过聚乙烯改性法     

浅析聚乙烯行业高压聚乙烯粒料气力输送系统的选型

目前国内外高压聚乙烯装置大多是巴塞尔工艺、埃克森、埃尼等工艺技术路线,都是由于物料的特殊性基本采用了密相输送,极个别的采用稀相输送。研究高压聚乙烯装置粒料气力密相输送不但可以解决本装置现存问题,还可以为聚烯烃行业提供有力支持,鉴于国内近5年频繁的在建及即将投产的高压聚乙烯装置,基于上述原因,文章详细论述高压聚乙烯装置粒料密相输送与稀相输送的理论差别,并调研国内约20套高压聚乙烯装置粒料输送存在的共性问题,展开论述,为高压聚乙烯装置后续粒料输送系统选型提供可参考性。     

聚乙烯合成技术的探讨和比选

随着聚乙烯合成技术的不断发展,通过改变聚合反应的条件、催化剂、助剂、加工方法等手段,从而得到不同性能的聚乙烯树脂产品,本文论述了LDPE、HDPE、LLDPE、mPE、UHmWPE和POE不同的聚乙烯合成技术,并介绍了不同聚乙烯合成技术的现存装置情况、工艺流程、产品用途、装置投资、产品价格、生产成本等方面内容,也对其进行技术路线比选,为聚乙烯装置工艺路线的选择提供依据。     

挤压造粒机水室夹持系统改进

挤压造粒机是聚丙烯、聚乙烯树脂的主要加工设备,承担着聚合后粉状聚合物从计量,喂料,混炼,挤出,切粒,分离,干燥等重要工艺程序.沈阳石蜡化工有限公司10万t/a聚乙烯装置对一台日本KOBE公司制造的挤压造粒机夹持系统进行了技术改造.通过技术改造解决了夹持压力升高的问题.     

试样厚度对聚乙烯拉伸性能的影响

通过对不同厚度聚乙烯试样的拉伸试验进行分析.结果表明,试样厚度对聚乙烯的强度、应变、拉伸模量均有较大影响,对单位面积的屈服吸收能没有影响;现有塑料制品设计中,材料的拉伸性能和制品厚度为独立参数的做法存在隐患.     

低分子量聚乙烯熔融接枝马来酸酐的研究

研究了吉林石化高密度聚乙烯装置副产低分子量聚乙烯与马来酸酐(MAH)的融熔接枝反应,考察了单体、引发剂用量、反应时间、温度对接枝率的影响。马来酸酐接枝低分子量聚乙烯应用于PE/CaCO3体系的性能测试结果表明,接枝物可以起到偶联剂的作用,改善体系的性能。     

Chlorocarboxylation of polyethylene. II. Reaction mechanism of the process

Chlorocarboxylated polyethylene (CCPE) is produced by simultaneous reaction of chlorine and maleic anhydride (MA) with polyethylene (PE). Hydrogen atoms on the PE chain are substituted either by chlorine atoms or by maleic anhydride moieties. The reaction mechanism involves creation of an active site, i.e. a radical on the PE chain. There is competition between chlorine and MA molecules for the reaction with this macroradical. Chlorine reacts to give chlorinated polyethylene (CPE) type segments, while MA reacts as a single unit (as chloro derivative) without forming any graft copolymer. There is a marked reduction in the rate of chlorination of PE due to the presence of MA. This is probably due to the competitive nature of the process and the radical scavenging action of MA.     

Chlorocarboxylation of polyethylene. I. Preparation and structure of chlorocarboxylated polyethylene

Chlorocarboxylated polyethylene (CCPE) is produced by simultaneous reaction of chlorine and maleic anhydride (MA) with polyethylene (PE). Low concentrations of the carboxyl groups in CCPE have been quantitatively estimated by dye interaction method and non-aqueous titration procedure. IR spectroscopic data are presented for the structural characterization of CCPE. During chlorocarboxylation, maleic anhydride can be anchored to the backbone chlorinated PE (CPE) chain as a chlorinated single monomeric unit without forming any graft copolymer of short branches.     

辽化HDPE装置浆液外循环技术改造后釜内的聚合过程分析

通过对辽阳石油化纤公司高密度聚乙烯淤浆聚合装置外循环撤热技术改造前后生产GF7750M牌号产品时聚合过程的工程分析,发现了釜内聚合过程特征的变化,提出了聚乙烯蜡含量的明显上升是引起聚合物粘壁加剧的最直接原因,并通过分析得出了可能导致聚乙烯蜡含量上升的主要因素以及进一步提高装置生产能力的可能性和主要手段。     

An in situ matrix functionalization approach to structure stability enhancement in polyethylene/montmorillonite nanocomposites prepared by intercalative polymerization

This paper discusses a strategy of enhancing the structure stability of polyethylene/montmorillonite (PE/MMT) nanocomposites prepared by intercalative polymerization technique. The chemistry centers on an in situ, controlled PE matrix functionalization that is made possible by engaging a reactive comonomer in the intercalative polymerization process to intentionally anchor in the formed PE matrix ready-to-functionalize reactive groups. Thus, ethylene polymerization was conducted in the presence of p-methylstyrene (p-MS) using an OMMT (organically modified MMT)-intercalated metallocene catalyst (Et[Ind]₂ZrCl₂ in combination with MAO), resulting in p-MS-containing PE/OMMT nanocomposites. Subsequent functionalization of the PE matrix then facilely and selectively occurred on the benzyl group in the p-MS unit, including a free radical maleation reaction and a butyllithium-initiated metallation reaction which was followed by an anionic graft-from polymerization of methyl methacrylate (MMA), under very mild reaction conditions. The in situ-incorporated functional groups, including the pendant maleic anhydride groups and the polar poly(methyl methacrylate) (PMMA) side chains, significantly improved miscibility between the PE matrix and laminated silicate layers of MMT, leading to effective stabilization of the nanocomposite structure against processing.     

基于有限元的内肋增强聚乙烯螺旋波纹管结构优化

为减小聚乙烯(polythene以下简称PE)的用料,同时保证环刚度基本不变,对内肋增强PE螺旋波纹管进行了结构优化。利用Solidworks和ANSYS workbench进行联合仿真,建立了内肋增强PE螺旋波纹管环刚度仿真测试的有限元模型,并通过环刚度理论计算模型对其进行了验证。将波纹管内肋截面的结构高度、圆弧半径、圆角半径和内肋角度作为设计变量,以单位长度波纹管PE的用料体积作为结构优化目标,以波纹管的环刚度作为约束条件。利用ANSYS workbench中的Design Exploration模块,求得设计变量对优化目标和约束条件的影响,及优化目标和约束条件对各设计变量的敏感度,从而得到设计变量的优化解。结构优化后的内肋增强PE波纹管,在环刚度基本保持不变的情况下,单位长度波纹管的PE用料体积减少了7.72%,能有效降低用料成本。     

PE管过滤器在盐水精制中的应用

介绍了加装PE管过滤器作为二次过滤装置后的效果及经济效益。指出改进及完善过滤流程后，盐水质量提高，耗电费用降低。     

The effect of transcrystallinity on the transverse mechanical properties of single-polymer polyethylene composites

The microstructure of polyethylene (PE)/PE composites, consisting of the high-density PE (HDPE) matrix and ultrahigh molecular-weight PE (UHMWPE) fibers, was investigated. Single-fiber composites were prepared and analyzed in a hot-stage crystallization unit attached to a polarizing microscope, aiming to find out how the conditions of crystallization affected the transcrystallinity (tc) growth at the fiber-matrix interface. Thermal treatments leading to two extreme microstructures, of either maximum or minimum thickness of the transcrystalline zone, were sought. It was found that a uniform transcrystalline layer was developed on the UHMWPE fiber from the HDPE melt under isothermal conditions, whereas rapid cooling from the melt prevented the generation of tc. The mechanical properties of unidirectional composite laminae either with or without the transcrystalline zone were measured. A comparison of the transverse strength predicted by theoretical models with the experimental values revealed good interfacial adhesion in the PE/PE system. It was shown that the tc growth had a negligible effect on the composite mechanical properties in the longitudinal direction, whereas it resulted in a 50% decrease of the transverse tensile strength and strain to failure. Scanning electron microscopy attributed that observation to premature brittle failure at tc/tc contact regions. © 1995 John Wiley & Sons, Inc.