聚丙烯气相反应器工艺参数的计算和控制

以液相本低聚合和气相聚合组合式聚丙烯（PP）装置生产多相共聚PP产品为例，推导出了多相共聚PP生产中气相反应器工艺参数之间的关系式，并讨论了工艺参数对产品性能的影响，通过控制气相反应器的乙烯进料量与气相比，改变产品的抗冲击性能，乙烯含量越高，产品的抗冲击性能越好，刚性越差，无定形二聚物的含量越高，产品的抗冲击性能越好，但刚性相对降低。     

Spheripol工艺生产高抗冲聚丙烯

介绍了Spheripol工艺生产高抗冲聚丙烯产品的方法,采用两步复合工艺生产嵌段聚丙烯,第1步采用环管反应器进行丙烯液相均聚反应,第2步采用流化床反应器进行丙烯均聚物与乙烯单体气相共聚反应,即在气相反应器中,利用来自环管反应器中的均聚物的残余活性,加入乙烯和补充的丙烯及氢气实现乙-丙共聚,共聚物的生成使最终产品的抗冲性能大大提高,尤其是低温下的抗冲性能。     

乙烯对聚丙烯共聚产品性能的影响

分析了乙烯对聚丙烯共聚产品的性能结构影响,可以给生产聚丙烯共聚产品提供参考.     

无规共聚聚丙烯乙烯加入量控制方法的改进

乙烯加入量的控制对无规共聚聚丙烯的产品质量,包括产品中乙烯含量、熔融指数以及等规度等都起着至关重要的作用,同时乙烯加入环管反应器中有加剧反应的作用。但是由于环管反应器产量动态变化,需频繁调整乙烯加入量以保证产品质量,这又会导致反应产生波动。文章结合乙烯加入量与丙烯加入量,反应热等关系,推导乙烯加入量自动控制程序,在无规共聚聚丙烯生产过程中,使用效果良好,反应平稳,质量稳定。     

兰州石化生产出三元无规共聚聚丙烯

正新近,兰州石化乙烯厂聚丙烯装置生产出三元共聚产品EPB08F。该产品是一种三元共聚聚丙烯树脂,由丙烯、乙烯、丁烯三种烯烃单体,在反应器内经过一次共聚而生产的无规共聚聚丙烯产品。通过改变分子链的有序性和结晶性,特殊的分子链结构赋予了其较低的热封温度,产品广泛应用于热密封、电容器薄膜、金属复合膜、食品包装膜等行业,具有较高的经济附加值。     

聚丙烯抗冲共聚产品2500H的开发

采用反应器串联操作的方式,在气相反应器中聚合生成高抗冲的共聚聚丙烯2500H.结合Novolen聚丙烯工艺特点,通过试生产确定出生产工艺条件和反应物的性能：高抗冲共聚聚丙烯的MFR为1.5-2.5 g·（10min）-1,乙烯含量为9％～13％,二甲苯可溶物含量为18％～23％,产品低温抗冲击性能优良.     

乙烯进料比对无规共聚聚丙烯性能的影响

在聚丙烯双环管反应器中控制双环管氢气浓度相同,采用不同乙烯进料比生产无规共聚聚丙烯树脂,通过差示扫描量热仪(DSC)、凝胶色谱分析仪(GPC)及核磁共振仪(13C-NMR)进行表征.结果表明,乙烯进料比对产品性能有较大影响,当第一环管加入较多乙烯、第二环管加入相对较少乙烯时,产品冲击强度及结晶温度降低,但对分子链结构、相对分子质量及其分布几乎没有影响.     

CPP薄膜专用三元共聚聚丙烯的结构与性能

分析了流延聚丙烯薄膜专用二元无规共聚聚丙烯W0723F与3种三元无规共聚聚丙烯的基本热力学性能、凝聚态结构、相对分子质量及其分布、结晶性能及流变性能。结果表明:二元无规共聚聚丙烯弯曲模量高,熔点高;3种三元无规共聚聚丙烯中1-丁烯含量相差不大,摩尔分数为5.1%~5.4%,乙烯含量相差较为明显,摩尔分数为3.0%~9.0%;两种进口产品的分子链序列结构中包含乙烯共聚链段,熔点低、熔融峰宽、晶体粒径小,产品具有较低的起始热封温度;流变性能分析表明,国产产品的加工流动性较好。     

聚丙烯超高抗冲共聚产品SP179生产和微观分析

通过确定气相反应器中的乙烯/乙烯+丙烯和氢气/乙烯的组分,生成较多的乙丙橡胶,使聚丙烯抗冲共聚产品SP179具有较高的抗冲强度.通过对产品的微观分析,指出橡胶相含量、乙烯含量、平均橡胶粒子粒径、橡胶粒子分散情况是影响产品冲击强度的因素.     

扬子石化首创聚合反应器减粘新技术

<正>日前,公司成功开发减粘新技术并进行了首次工业化试运行,攻克了共聚反应器加入乙烯后发粘的技术难题,可大幅提升聚合物产品性能,并为后续开发高乙烯含量的高端聚烯烃产品打下基础。该技术属于中国石化首创,已申请国家专利2项,获得授权专利1项。公司1PP装置由于缺乏减粘手段,制约了该装置生产高乙烯含量的共聚聚丙烯。公司研究院和浙江大学合作,通过小聚和中试研究,自主开发了减粘新技术可解决聚合体系发粘问题。科研人员通过中试装置试验,确定了工艺操作     

DIRECT OXIDATION OF ETHYLENE TO ACETALDEHYDE IN A HOLLOW FIBER MEMBRANE REACTOR†

A hollow fiber membrane reactor, which resembles a tube-and-shell heat exchanger, was developed for homogeneous catalytic reactions with gas reactants and products. The gas stream flows through the tube side while the reaction takes place in the catalyst solution which fills the shell side. The separation load of product from the catalyst solution can be reduced by using a hollow fiber membrane reactor instead of a conventional bubble column reactor. The reactor operates in a plug-flow pattern with a large mass transfer area per unit volume of catalyst solution

This concept was investigated experimentally using the direct oxidation of ethylene to acetaldehyde reaction in an aqueous solution of palladium (H) chloride-cupric chloride with a silicone rubber membrane reactor and a polypropylene membrane reactor. It was experimentally demonstrated that membrane reactors could achieve higher production rates per unit volume of catalyst than the conventional sparged reactor. The experimental data were in good agreement with the predictions by the mathematical model. The conditions under which the membrane reactor will be more advantageous than the conventional sparged reactors can be readily ascertained with the analytical solution of the simplified membrane reactor model.     

Reactions of cyclohexane in a microwave discharge reactor

A study has been made of the reactions of cyclohexane in a continuous-flow microwave discharge reactor. Butene-1 and propylene were the major reaction products; ethylene and hydrogen were produced in smaller amounts. The distribution of reaction products was found to depend on the reactor pressure and flow-rate. The results show that the fragmentation of cyclohexane is not the sole source of butene-1. The insertion of nickel wire into the reactor enhanced the production of ethylene and propylene; yields of butene-1 were diminished. In the presence of nickel the production of ethylene and propylene became independent of pressure. When carbon dioxide was added to the cyclohexane feed the major reaction product was acetylene. The carbon dioxide did not react chemically. The yields of acetylene per unit energy input were found to be fairly high.     

聚丙烯反应器的动态模拟

针对聚丙烯生产中广泛采用的ＣＳＴＲ反应器,建立了了聚合过程的动态模型,包括固体物料和催化剂、氢气浓度、熔融指数的动态方程。本模型可以准确地计算ＣＳＴＲ反应器的浆液浓度、产物固含率、催化剂残贸率、熔融指数等重要的生产指标。对产品牌号切换过程的仿真结果表明,丙烯聚合反应的质量闭环控制能带来巨大的经济效益。     

聚丙烯EPS30R产品冲击强度波动原因分析

根据生产装置实际情况，对比相关数据分析讨论了聚丙烯产品EPS30R冲击强度波动的原因。结果表明，波动原因主要是原料中惰性组分高和装置局部换热器泄漏造成催化剂活性低，使催化剂加入量大，共聚性能差，导致最终产品中乙烯含量偏低、灰分高。同时，熔体流动速率控制偏高也是一个原因。在现有的条件下，通过加大流化气排放提高催化剂活性，改善了不利的因素。将熔体流动速率控制在1．2～1．5g／10min、乙烯质量分数控制在8．0％～8．5％时，产品性能可以得到改善。     

Controlled Air Oxidation of Plastic and Biomass in a Packed‐Bed Reactor

A packed‐bed reactor was established to study the effect of polypropylene (PP) content on the controlled air oxidation performance of a mixture of PP and sawdust (SD) at a fixed feed gas flow rate. Attention was focused on product yields, evolutionary behavior of the gas flow rate, and gas compositions. A higher PP content led to increased gas yield, lower solid yield, and substantially reduced liquid yield. The PP content significantly affected the gas composition and rate of gas production. Mixtures of plastic and biomass can be radically converted to gaseous and liquid products under controlled air oxidation conditions.     

抗冲聚丙烯FC709M的开发与应用研究

论述了基于Unipol工艺的中熔抗冲聚丙烯FC709M的生产过程,重点讨论了β/α比率、铝钛比、铝硅比、氢气乙烯比、丙烯乙烯比、聚合温度、反应温度等重要工艺参数对产品性能的影响,并对整个中熔抗冲聚丙烯FC709M的生产过程进行了全面系统的总结。     

Characterization of phase morphology of polymer melts (PP/PE blends) via rheology

The viscoelastic behavior of high impact polypropylene (PP) melts, a multiphase system with an isotactic PP matrix and inclusions consisting of mainly amorphous ethylene–propylene copolymer (EP), is strongly influenced by the size of small inclusions. The dynamic moduli of such two‐phase systems (reactor products) are well described by Palierne's emulsion model. For this analysis the reactor product is separated into matrix and dispersed phase via the different solubility in xylene. This analysis also provides information on the ratio interfacial tension to particle size of the dispersed phase. With morphology data (particle size) of the solidified heterophasic samples (Transmission Electron Microscopy), we estimate the interfacial tension between PP and EP copolymer via the emulsion model of Palierne and from the relaxation time spectra according to Gramespacher and Meissner. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007