本体聚合橡胶增韧苯乙烯系树脂反应器技术进展

综述了丙烯腈-丁二烯-苯乙烯(ABS)和高抗冲聚苯乙烯(HIPS)本体聚合工艺各种不同形式反应器的优缺点以及不同专利商的流程反应器组合特点。重点阐述了在工业放大过程中,反应器的选择依据和设计要点。提出对反应器组合流程的设计应该充分挖掘本体聚合的优势。     

微波强化聚磷酸铵聚合的研究

以磷酸二氢铵和尿素为原料,用微波反应器和马弗炉分别研究聚磷酸铵(APP)的聚合工艺条件.分别实验了不同反应器的反应温度、反应时间和原料配比等因素对聚磷酸铵中的五氧化二磷含量、氮含量、聚合度的影响.在产品质量相同的情况下,采用微波反应器聚合聚磷酸铵所需要的条件更加温和,并且能够强化聚磷酸铵的聚合.采用微波反应器聚合聚磷酸铵的最优条件:反应温度为200℃,聚合时间为40 min,磷酸二氢铵与尿素的物质的量比为1:1.1.得到的产品中五氧化二磷质量分数为69.05%,氮质量分数为14.13%,聚合度为38.     

挤出机作聚合反应器的探讨

本文目的是介绍一些在挤出机中进行的聚合反应和国外商品聚合反应器的操作性能数据,供预选聚合反应器参考。文中对螺杆挤出机反应器的设计和选用需要考虑的重要因素作了讨论。     

外循环反应器停留时间分布的计算(摘要)

<正> 本文结合丁基橡胶中试聚合流程对外循环反应器的停留时间分布进行了分布和计算,推导了下列类型外循环反应器停留时间分布的计算公式: 1.单釜有外循环的反应器:     

PS反应器结构对产品质量的影响

从聚苯乙烯树脂连续本体聚合反应机理和反应器选型原理的角度出发，针对不同结构的本体聚合反应器，阐述了其结构形式聚合反应器的混合、传热性能以及产品质量的影响。     

自由基聚合反应器中多尺度流场的模拟进展

自由基聚合过程中,由于混合、传递及聚合反应的相互作用使得反应器内部存在复杂的多尺度流场,例如宏观尺度的速度、浓度、温度分布,介观尺度的液滴粒径分布,微观尺度的聚合反应速率、聚合物分子量和多分散性指数分布。这些复杂的多尺度流场分布使得聚合反应器的模型化研究成为难题。本文较为系统地介绍了自由基聚合反应器中存在的多尺度现象;简述了微观尺度聚合物性质流场分布的模型化与模拟研究方法;从悬浮聚合和乳液聚合两个方面介绍了介观尺度液滴粒径分布的模拟研究进展;从非理想混合的角度阐述了宏观尺度多相流流场分布的研究进展。最后,本文分析了多尺度模型的耦合求解方法。本综述也有本文作者对这个领域的初步观点,可为聚合反应器的设计、优化和放大提供参考。     

基于尼龙6生产过程的聚合反应模拟优化

采用Aspen Plus模拟软件对己内酰胺水解聚合生产尼龙6工业过程进行模拟分析与优化,建立了尼龙6水解聚合生产工艺流程模型,考察了进料水含量,反应温度、前聚合管反应器压力、后聚合管反应器的真空度等影响低聚物生成的影响因素。模拟结果表明,通过降低生产工艺的反应温度、减少进料水含量、提高聚合管反应器的真空度以及降低反应器压力等方式均能有效降低聚合产品中环状聚物的含量。通过减少聚合反应过程中低聚物生成,提出了尼龙6工业生产过程中控制环状低聚物生成的工艺路线。     

气相聚丙烯反应器的研究进展

聚丙烯气相法工艺具有流程简单、操作简便、装置安全性好等优点,是当前聚丙烯工业中应用最为广泛和最有发展潜力的工艺。气相聚合反应器主要包括流化床反应器、立式搅拌床反应器和卧式搅拌床反应器三种形式。本文调研了气相聚合反应器的实验和模拟的研究现状及进展,以期能够为聚丙烯反应器的设计与优化提供理论指导。     

Ziegler-Natta/茂金属复合催化剂制备双峰聚乙烯

通过把茂金属催化剂负载在Ziegler-Natta催化剂上制备了ZM复合催化剂,在单一聚合反应器内研究了ZM催化剂用于乙烯聚合制备双峰聚乙烯的性能。考察了催化剂中茂金属化合物的含量、聚合过程中反应温度、助催化剂的用量和共聚单体1-己烯的用量对催化剂乙烯聚合性能的影响规律。结果表明：采用ZM催化剂可以在单反应器内催化乙烯聚合得到分子量分布呈双峰的聚乙烯,聚乙烯的分子量分布达到155,聚合活性可达2.52×10⁷ g/molMt·h。     

万吨级高吸水树脂光催化梯次引发聚合反应器工艺包开发及控制优化研究

以丙烯酸及盐溶液聚合和光催化梯次辐射能传递自由基聚合相结合的工艺流程,从工业化聚合装置的角度对丙烯酸系溶液聚合光催化反应器进行了剖析,研究了丙烯酸及盐溶液聚合复杂体系的热力学物性计算模型及其参数确定方法;从丙烯酸及盐聚合反应过程的光催化机理和反应动力学入手,基于梯次光催化反应动力学对万吨级工业化聚合装置全流程动态建模,进行反应器操作条件、动态特性、物态物性等分析,工业示范装置流程优化运行及工业化实验装置的带料调试。对聚合反应器体系进行项目开发评价,对指导项目开发具有重要的实践和指导意义。     

20kt/a PA6前聚合工艺的优化

介绍了20kt/aPA6聚合装置前聚合器的结构及工艺特点;分析了生产中前聚合工艺存在的问题,提出了解决措施;验证了前聚合器结构的设计参数。指出生产中由于前聚合器底部出料温度波动大,波动值达±8.08℃,影响了PA6切片的可纺性。通过降低前聚合反应的压力及加热联苯炉的温度,调整前聚合器顶部冷凝器的排汽温度,前聚合器底部出料温度的波动值可控制在±2.5℃,有效提高了PA6切片的质量。     

Bulk polymerization of styrene in plate and frame batch reactors

Thermal bulk polymerization of styrene in the plate and frame batch reactor i.s simulated with a mathematical model which accounts for chain transfer to monomer and gel effect. The design parameters are: the frame thickness, the temperature policy, and the level of prepolymerization in the feed. The recommended frame thickness with 27% prepolymerization is 5 in. The resulting polydispersities and number average chain lengths range from 2.2–2.3 and 2000–2100 respectively. The implementation of temperature policy, particularly the timing of the application of the coolant, is critical to obtain satisfactory polymer quality. When pure styrene feed is used the reactor displays thermal ignition unless the frame thickness is less then 2 in. For a 5 in. frame prepolymerization should be at least 25 percent to permit adequate temperature control.     

预聚反应器液位对生产能力的影响

分析预聚反应器的生产情况,讨论预聚反应器对生产和产品质量的影响,提出通过提出预矛反应器物料液位来提高装置生产能力的可行性。     

Experimental study and model simulation of a two-stage continuous polymerization process for polystyrene

Free radical solution polymerization of styrene in two stage polymerization process has been studied using a binary mixture of symmetrical bifunctional initiators. The continuous reactor system was composed of two reactor units; a prepolymerization reactor (e.g. stirred tank reactors) and a filled tubular reactor packed with static mixers. When the stirred tank reactor was used as a prepolymerizer, a feed stream to the filled tubular reactor was more viscous than the monomer/solvent mixture. It was of interest to investigate how the performance of the filled tubular reactor has been investigated by the feed of viscous prepolymer solution. A dynamic model of the continuous two stage polymerization process was presented by experimental data and model simulation. A reasonably good agreement between the model and the experimental data was obtained without using any adjustable parameters. The experimental results of the two stage polymerization were compared with the results without prepolymerization reactor. It was found that the addition of a prepolymerization reactor has almost no effect on the performance of the filled tubular reactor.     

预聚釜搅拌器的优化设计

在相似理论指导下,应用试验结果及搅拌放大技术,实现对聚合釜搅拌器的优化设计,选定搅拌器型式、规格,使其搅拌效果满足设计要求,满足用户使用要求。     

PET连续聚合工艺流程优化改造

采用将五釜流程改为四釜流程的方法,即以酯化预聚塔一个反应器取代五条工艺流程的第二酯化釜和第一预缩聚釜两个反应器,对PET聚合工艺流程优化,改造后的PET单线生产能力由160t/d提高到200 t/d,其单耗PTA由改造前的865 kg/t降至863 kg/t,EG由338 kg/t降至334 kg/t,降低了成本,提高了产品质量。     

Millimeter‐size polyethylene hollow spheres synthesized with MgCl2‐supported Ziegler‐Natta catalyst

Polyethylene hollow spheres with diameters of 0.4–2 mm were synthesized by a two‐step slurry polymerization in a single reactor with a spherical MgCl₂‐supported Ziegler‐Natta catalyst activated by triethylaluminum, in which the first step was prepolymerization with 0.1 MPa propylene and the second step was ethylene polymerization under 0.6 MPa. The prepolymerization step was found necessary for the formation of hollow spherical particles with regular shape (perfectly spherical shape). The effects of adding small amount of propylene (propylene/ethylene < 0.1 mol/mol) in the reactor after the prepolymerization step were investigated. Average size of the polymer particles was increased, and the polymerization rate was markedly enhanced by the added propylene. Development of the particle morphology with polymerization time was also studied. The polymer particles formed by less than 20 min of ethylene polymerization showed hollow spherical morphology with thin shell layer. Most of the particles had ratio of shell thickness/particle radius smaller than 0.5. By prolonging the ethylene polymerization, the shell thickness/particle radius ratio gradually approached 1, and the central void tended to disappear. Central void in polymer particles formed from smaller catalyst particles disappeared after shorter time of polymerization than those formed from bigger catalyst particles. The shell layer of the hollow particles contained large number of macro‐, meso‐ and micro‐pores. The mesopore size distributions of four typical samples were analyzed by nitrogen adsorption–desorption experiments. A simplified multigrain model was proposed to explain the morphogenesis of the hollow spherical particles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43207.     

The production of rubber-modified polystyrene. Some criteria influencing the selection and design of the agitator system

The importance of selecting the most suitable form of agitation for the prepolymerization step in the production of rubber-modified polystyrene by a bulk polymerization procedure is related to the non-Newtonian behavior of the polymerizing system and to the existence of a minimum shear rate requirement. The procedure for the design and calibration of a small-scale reactor system is described which is shown to produce an adequate phase inversion of the prepolymer and from which data can be evaluated for any change in scale of the operation. Structural patterns in the final polymer are linked with average shear levels in the reactor.     

生产聚苯乙烯预聚合釜的作用和选型

本文就聚苯乙烯生产技术中预聚合工艺的特点和预聚合釜的作用,从反应动力学角度和围绕提高产品质量的角度进行探讨。