乙烯气相法合成醋酸乙烯催化剂单管试验研究

本文叙述了一种新型乙烯氧乙酰化合成醋酸乙烯 （ Ｖ Ａ Ｃ） 催化剂在单管装置中的运行情况。试验表明, 经过长时间运行后催化剂仍具有较高的催化活性与选择性。同时研究了系统传热对试验结果的影响。长时间单管运行后对该催化剂进行剖析, 发现其物理化学性能及表面结构等均无明显变化, 表明该催化剂具有良好的稳定性。     

乙烯气相法合成醋酸乙烯催化剂单管试验研究

本文叙述了一种新型乙烯氧乙酰化合成醋酸乙烯(VAC) 催化剂在单管装置中的运行情况。试验表明, 经过长时间运行后催化剂仍具有较高的催化活性与选择性。同时研究了系统传热对试验结果的影响。长时间单管运行后对该催化剂进行剖析, 发现其物理化学性能及表面结构等均无明显变化, 表明该催化剂具有良好的稳定性。     

CTV系列乙烯法醋酸乙烯催化剂工业应用

对比了几种乙烯法制醋酸乙烯的国产与进口催化剂的工业应用情况，结果表明，国产CTV系列醋酸乙烯催化剂的各项性能均优于同类进口催化剂水平，尤其是CTV-Ⅳ型催化剂在活性和选择性方面已领先于同类催化剂的国际水平。     

乙烯气相法和乙炔气相法合成醋酸乙烯的催化剂的研究进展

合成醋酸乙烯的工艺主要有乙烯气相法和乙炔气相法两种工艺.乙烯气相法普遍采用的催化剂为Pd-Au/SiO2,它的缺点是成本高、寿命短、易失活;乙炔气相法采用最广泛的是醋酸锌/活性炭催化剂,具有寿命短、活性低等方面的缺点.概述了乙烯气相法和乙炔气相法生产醋酸乙烯所需催化剂的现状,指出了主要催化剂存在的缺点,并提出了解决措施...     

新型丙烯醛和丙烯酸催化剂单管工艺试验研究

在模拟工业生产装置上，对所开发的新型丙烯氧化制丙烯醛和丙烯醛氧化制丙烯酸催化剂的性能进行了研究，确定了催化剂的操作条件，并在该工艺条件下考察了催化剂的稳定性。结果表明：丙烯氧化制丙烯醛在空速为800～1000h^-1、盐浴温度310℃、丙烯∶空气∶水=10∶73∶17时，丙烯转化率≥98%，丙烯醛收率≥81%，丙烯醛 丙烯酸总收率≥92%，COx≤4%；丙烯醛氧化制丙烯酸在空速为1450h^-1，盐浴温度为258℃叶。丙烯醛转化率≥98%，COx≤3%。催化剂运行1000小时以上，性能良好。     

乙炔法合成醋酸乙烯催化剂的研究进展

从催化剂载体、活性组分、反应机理三个方面回顾了国内外乙炔法合成醋酸乙烯催化剂的研究进展，并对今后的发展方向进行了展望。     

醋酸乙烯CT-2型催化剂使用寿命的预测

本文对已在工业装置上分别应用一年和两年的醋酸乙烯CT-2型催化剂,进行了分区分层取样,对所获样品进行了各种物化性能和机械性能的测定,并将测定结果与工业运转的实际情况进行关联认为CT-2型催化剂失活的主要原因是:(1)由于Pd-Au粒子的长大使其分散度下降,树脂状物及结焦的存在,使催化剂的比表面和孔容降低.在此基础上预测已反应17665小时的CT-2型催化剂的使用寿命尚可延长一年。     

Catalyst Pellet Shape Specialization for Ethylene Acetoxidation to Vinyl Acetate

ＣａｔａｌｙｓｔＰｅｌｌｅｔＳｈａｐｅＳｐｅｃｉａｌｉｚａｔｉｏｎｆｏｒＥｔｈｙｌｅｎｅＡｃｅｔｏｘｉｄａｔｉｏｎｔｏＶｉｎｙｌＡｃｅｔａｔｅＪｕＭｅｎｇｊｏｅ；ＸｕＫｅ；ＷａｎｇＳｈａｎｇｄｉ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＥｎｇｉｎｅｅ...     

乙烯-乙酸乙烯酯共聚物中乙酸乙烯酯的红外光谱法测定

利用ATR技术测量样品的红外光谱,采用偏最小二乘法对所测光谱进行分析,建立了一种快速分析方法;对乙烯-乙酸乙烯酯共聚物中乙酸乙烯酯进行测定。结果表明：标准曲线线性关系良好,相关系数为0．99985,方法简单快速,结果可靠。     

EVA增韧聚乳酸的性能研究

对乙烯-醋酸乙烯共聚物(EVA)增韧聚乳酸(PLA)体系的力学、热学和结晶性能进行了研究,并分析了增塑剂邻苯二甲酸二辛酯(DOP)对PLA/EVA增韧体系性能的影响。结果表明,PLA/EVA的质量比为80/20时,二元共混体系的力学性能最佳;PLA/EVA/DOP的质量比为80/20/8时,三元共混体系的力学性能最佳;EVA对PLA的T_g、T_m和结晶度影响不大,但DOP会使T_g和T_m降低,而结晶度得到很大提高;偏光显微镜观察结果也证实了DOP的加入有利于PLA的结晶。     

乙烯-醋酸乙烯共聚物中乙烯含量测定方法研究

主要研究了乙烯-醋酸乙烯共聚物(EVA)中乙烯含量的测定方法。对样品制备、溶剂选择、体系中含水量、皂化温度、皂化时间等影响测定的主要因素进行了探讨,找到了合适的测定条件。通过与真实值进行比较,皂化法的相对误差小于0.1%。能满足EVA研究中对乙烯含量的测定要求。     

Miscibility Between Ethylene Vinyl Acetate Copolymers and Tackifier Resins

A series of ethylene vinyl acetate copolymer (EVA) were blended with various kinds of tackifiers and the miscibility between the components was investigated. The miscibility of the blend is illustrated as a phase diagram. The EVA and modified rosin systems tended to have a phase diagram with lower critical solution temperature (LCST), whereas the EVA and petroleum resin systems tended to have that with upper critical solution temperature (UCST). The phase diagrams of EVA/tackifier resins systematically changed as VAc content in the copolymer increased, which is accounted for by the classical Flory-Huggins theory.     

Miscibility Between Ethylene Vinyl Acetate Copolymers and Tackifier Resins

A series of ethylene vinyl acetate copolymer (EVA) were blended with various kinds of tackifiers and the miscibility between the components was investigated. The miscibility of the blend is illustrated as a phase diagram. The EVA and modified rosin systems tended to have a phase diagram with lower critical solution temperature (LCST), whereas the EVA and petroleum resin systems tended to have that with upper critical solution temperature (UCST). The phase diagrams of EVA/tackifier resins systematically changed as VAc content in the copolymer increased, which is accounted for by the classical Flory-Huggins theory.     

Dynamic Mechanical Properties of Carbon Black Filled Ethylene Vinyl Acetate Rubber

Abstract

The dynamic mechanical properties of ethylene vinyl acetate (EVA) rubber filled with different loadings of carbon black and at different degrees of crosslinking were studied over a wide range of temperatures (-150° to +200°C). The loss tangent (tan δ) versus temperature plots indicated presence of different transitions. The α-transition (or the glass-rubber transition) corresponding to the maximum in tan δ value, occurred at ?17°C, which is the principal glass-transition temperature (abbreviated as T _g) of EVA rubber. The γ-transition occurred in the temperature region of ?125° to ?135°C, while the β-transition appeared as a shoulder in the temperature region of ?65° to ?75°C. Besides, there was also a high tempeature transition around +62°C which is known as liquid to liquid transition (T _1.1). Incorporation of carbon black filler did not cause any shift of T _g, while the tan δ peak values at T _g decreased sequentially with increase in filler loading. The γ- and β-relaxations were found to be insensitive to filler loading. The T _1.1 transition, however, was found to be suppressed by incorporation of carbon black filler particularly at high loading. Extent of crosslinking did not influence the T _g But, the T _1.1 transition, which was prominent with the lightly crosslinked system was found to be suppressed at high level of crosslinking. Strain dependent dynamic mechanical properties under isothermal conditions showed that the secondary structure breakdown of carbon black filler under the effect of strain amplitude is influenced by the degree of crosslinking of EVA rubber.     

乙烯-醋酸乙烯(EVA)树脂生产及市场分析

综述了国内乙烯-醋酸乙烯(EVA)的生产及市场情况,对发展趋势进行了分析及预测,并对国内EVA行业发展提出了几点建议.     

从醋酸乙烯废触媒中回收醋酸锌制备无毒磷酸锌

提出用微波-超声波联用技术对废触媒进行脱附处理的方法,同时回收活性炭和醋酸锌,利用醋酸锌制备磷酸锌。