共查询到20条相似文献,搜索用时 93 毫秒
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氨纶是一种性能优良的新型纺织纤维,因其具有极好的回弹性而广泛地应用到各种弹力织物中,具有广泛的应用价值和发展前景。但美中不足的是稳定性差,特别是聚醚型氨纶,在其聚合纺丝生产过程中,氨纶纺丝液因时间、温度等的作用,其分子结构发生裂变,氨纶纺丝液的性能随之变化,将直接影响最终产品的性能。纺丝液的制备可分为连续式生产法和间歇式生产法两种。所谓间歇式生产法就是聚醚和二异氰酸酯先预聚,其预聚物再与链增长剂反应生成纺丝原液,存放、脱泡、纺丝得最终产品。德国拜耳公司曾研究过预聚物的存储对纺丝液性能的影响,研究… 相似文献
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<正>日前,河南新乡化纤股份有限公司总投资达17.5亿元、年产4万t的超柔软氨纶项目在新乡经济技术开发区奠基。该项目是在现有年产2万t氨纶生产线的基础上,为满足市场对新型氨纶的需要而兴建的。该项目采用国际先进的连续聚合、干法纺丝技术和装备,产品具有质量优、成本低、竞争力强、效益好的特点。该项目计划建设工期为24个月,总建筑面积近8万m2,将是新乡化纤历史上一次性投资最大的项目。项目建成投产后预计年销售收入可增22亿元。 相似文献
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刘青 《化工自动化及仪表》2000,27(1):13-15
介绍了氨纶工程DCS系统方案设计的主要性能、基本原理和基本构成。提出了基于间歇式聚合生产工艺流程的DCS系统方案设计原则和内容,并将其应用于生产实际中。 相似文献
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以烟台泰和新材料股份有限公司投资建造的舒适氨纶项目为背景,对其连续聚合工艺中采用的关键设备——纺丝甬道进行技术研究和创新改造。研究了氨纶丝条在甬道中的变化过程,进行了新型甬道的创新改造,分析了甬道的物理结构及加热保温回收系统对纺丝性能指标的影响,制定了甬道加热系统的工艺参数和使用维护方案,以保证甬道能合理满足工艺要求。实践证明:在新型甬道中纺出来的氨纶的力学性能指标达到了国际同类产品领先水平。 相似文献
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Marcelo Kaminski Lenzi Fabricio Machado Silva Enrique Luis Lima Jos Carlos Pinto 《应用聚合物科学杂志》2003,89(11):3021-3038
Emulsion and suspension polymerization processes have widely been studied for more than 40 years. Although both polymerization processes are performed in heterogeneous media, each one presents its own typical characteristics, such as the particle size distribution, molecular weight distribution, polymer particle nucleation rate, and polymerization rate. In this study, semibatch styrene suspension polymerizations were carried out with feed compositions typical of emulsion processes. The initial reactor charge resembled the recipe of standard styrene suspension polymerizations, and the emulsion polymerization constituents were added during the batch. The influence of the moment at which the emulsion feed was started on the course of the polymerization and the effects of the feed on the polymer properties were analyzed. The polymer particle morphology and the average molecular weights changed very significantly with the emulsion feed time, and the changes could lead to the production of broad molecular weight distributions. Core–shell polymer particles could also be obtained, with the core being formed of polymer particles originating from the suspension polymerization process and the shell being formed of polymer particles originating from the emulsion polymerization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3021–3038, 2003 相似文献
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Dramatic changes occur during the initial stages of olefin polymerization over heterogenous catalysts. As polymer accumulates, the catalyst fragments and the void space within the growing particle becomes filled with polymer. The changing monomer transport rate to the active sites, dissipation of heat and stress with the particle, and eventually, dispersion of catalyst fragments within the growing particle can control the polymerization. We focus on the changes in, and influence of, polymer, catalyst and void morphology during the nascent polymerization for silica supported chromium oxide catalysts. We find that the course of the polymerization depends on the initial stages yet is seldom considered in polymerization models. We review several years of morphological characterization that identify the important physical phenomena which occur during nascent heterogeneous olefin polymerization. 相似文献
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This review is focused on the features, preparation and applications of uniform cationic polymer latex particles, as well as on the formation mechanism of uniform latex particles. Substantial progress in the size and shape control of polymer latex particles has been made using several methods such as dispersion polymerization, conventional emulsion polymerization, surfactant‐free emulsion polymerization and seeded emulsion polymerization. Uniform cationic polymer latex particles have wide applications such as drug carriers, diagnostics, templates and additives. However, two major problems are the inhomogeneous size and low surface charge density, which limit further functionalization and the application of cationic polymer latex particles. Finally, the future trends and perspectives are described. Copyright © 2012 Society of Chemical Industry 相似文献
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有机高分子絮凝剂作为具有优势的一类高分子絮凝剂,目前广泛应用于废水处理工艺中.本文综述了絮凝剂的种类、合成方法及其在废水处理中的应用,絮凝剂的聚合方法主要包括水溶液聚合法、反相乳液聚合法以及反相悬浮聚合法.分析了有机高分子絮凝剂的研究方向. 相似文献
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超薄聚合物表面与滴状冷凝的研究 总被引:5,自引:0,他引:5
采用等离子体聚合技术在黄铜管外表面制备了六氟丙烯、六甲基二硅氧烷的超薄聚合物薄膜,实现了水蒸气的滴状冷凝.对不同冷凝表面的传热性能进行了实验测定,并对聚合膜的表面性能进行了测试和估算.分析讨论了聚合工艺条件对滴状冷凝传热及膜与基材粘着性能的影响. 相似文献