Viscoelastic properties of polyarylene ether nitriles/thermotropic liquid crystalline polymer blend

Polyarylene ether nitriles (PEN)/thermotropic liquid crystalline polymer (TLCP) blend was prepared via melt mixing. The immiscible phase morphologies, linear and nonlinear, as well as transient viscoelastic properties of the blend were studied using SEM, rheometer, and DMA. The linear dynamic viscoelastic behavior of the blend shows temperature dependence due to further evolution of the immiscible morphology and, as a result, the principle of time‐temperature superposition (TTS) is invalid. In the steady shear flow, the discrete TLCP phase is difficult to be broken up because of the high viscosity ratio of the blend systems, while is easy to be coarsened and followed by elongation, and finally, to form fibrous morphology at high TLCP content and high shear level. During this morphological evolution process, the transient stress response presents step increase and nonzero residual relaxation behavior, leading to increase of the dynamic viscoelastic responses after steady preshear. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Effects and properties of poly(arylene ether benzonitrile)s of various molecular weights blended with sulfonated poly(ether ether ketone)

Poly(arylene ether benzonitrile) (PAEBN) was synthesized with 2,6‐dichlorobenzonitrile and biphenol. PAEBNs with various molecular weights (MWs), 1,640,000 and 185,000 g/mol, were synthesized by control of the stoichiometry of the monomers and were blended with sulfonated poly(ether ether ketone) (SPEEK). The effects of MW on the water uptake, swelling, methanol permeability, and proton conductivity of the SPEEK/PAEBN blend membranes were investigated. The molecular mobility of the SPEEK/PAEBN blends was also examined in this study. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

世界乙烯工业及其进展

阐述了世界乙烯产能需求现状，近扑扩能增产预测，乙烯原料分析以及乙烯生产的技术进展。     

乙烯裂解炉对流段局部结构设计改进

介绍了乙烯裂解炉对流段的结构功能,各部件局部结构的改善设计。     

Performance of the polymer- and oxide-supported triphase catalysts and effect of ultrasound on their stabilities

In this study, several trialkylamines were immobilized on chloromethylated polystyrene (CMPS), silica gel, and alumina to prepare triphase catalysts for catalyzing the etherification reaction of allyl bromide (the organic reactant) and sodium phenolate (the aqueous reactant). The reactor was agitated mechanically or with the aid of ultrasonic vibration. Performances of the prepared catalysts were compared, and the effect of imposing ultrasound was investigated based on the activity, selectivity, and stability of the catalyst. Experimental results show that tri-n-propylamine is the best active species when CMPS is used as the support, while tri-n-butylamine is the best when SiO₂ and Al₂O₃ are employed as the supports. The CMPS-supported catalyst is far better than the SiO₂- and Al₂O₃-supported catalysts in activity and selectivity but not in stability. Imposing the ultrasound can effectively increase the reaction rate. Mechanical agitation at a low speed with the imposition of ultrasonic vibration not only results in a conversion slightly higher than the case with a high mechanical agitation speed without ultrasonic vibration, but also gives a constant stability for the CMPS-supported catalyst.     

乙烯裂解炉辐射段炉顶密封结构优化设计

乙烯裂解炉的炉顶密封效果关系到装置的安全、稳定运行.针对现行的密封结构,进行了合理的技术改造和优化设计,并经实际投入使用,效果良好,也可进一步推广到类似的炉型上.     

乙烯裂解炉内传递和反应过程综合数值模拟Ⅱ.反应管内传递和反应过程的数值模拟

采用乙烯裂解炉传递反应过程综合数学模型中的反应管数学模型，对工业裂解炉反应管进行了系统的数值模拟，得到了反应管内流场、温度场和浓度场的详细信息，揭示了反应管内流动、传热、传质和裂解反应的基本特点。模拟结果表明，沿反应管轴向油气吸热升温，裂解反应加剧，产物产率逐渐发生变化；沿反应管径向存在明显的流体流速和温度的变化，而产物产率的变化不如流体流速和温度的变化明显。通过比较湍流粘度和分子粘度的大小，认为29．975～30mm的径向区域为层流层，层流层的存在使得临近管壁的区域内流体流速和温度变化显著。     

CpTi(dbm)Cl_2催化烯烃聚合及其聚合物性质

开发了一种新型非茂聚烯烃催化剂———CpTi(dbm)Cl2,考察了催化剂在均相及负载条件下对乙烯及乙烯-1-己烯共聚的催化行为。催化剂在均相条件下对乙烯聚合的催化活性较低,但用MgCl2和MgCl2/SiO2复合双载体对催化剂进行负载后,催化乙烯聚合具有非常好的催化活性。催化剂还具有良好的共聚能力及良好的氢调敏感性。     

正庚烷-甲苯-三甘醇三元体系液-液相平衡数据的测定与关联

利用气相色谱法测定了常压下２５℃、４０℃和５０℃时正庚烷－甲苯－三甘醇体系的液－液相平衡数据，采用峰面积归一化法定量，所得数据准确、可靠。用ＮＲＴＬ模型对所测数据进行了热力学关联，求出了相应的模型参数。用该模型对本三元体系进行了预测，结果令人满意。     

吸附法脱除乙烯中少量氧气的吸附剂研究

采用重量法在电子天平上研究了Ｃ２Ｈ４和Ｏ２单组份在５Ａ、１３Ｘ、丝光沸石和碳分子筛等不同吸附剂上的吸附平衡性质和扩散动力学性质。结果表明，在沸石类吸附剂上，Ｃ２Ｈ４的平衡吸附量远大于Ｏ２的平衡吸附量，Ｃ２Ｈ４的吸附扩散速率也大于Ｏ２的扩散速率；在碳分子筛吸附剂上Ｃ２Ｈ４的平衡吸附量大于Ｏ２的平衡吸附量，但Ｏ２的吸附扩散速率远大于Ｃ２Ｈ４的扩散速率，其扩散系数是Ｃ２Ｈ４的２３９倍。单柱评价结果表明，Ｃ２Ｈ４－Ｏ２混合组份通过该碳分子筛吸附剂时，Ｏ２的破点时间长，Ｃ２Ｈ４的纯度可达１００％。加压有利于选择吸附Ｏ２，而且加压吸附、常压脱附再生性能好。该碳分子筛是脱除高浓度乙烯中少量氧气的理想吸附剂。