聚氯乙烯生产过程全流程调度

研究了电石法制聚氯乙烯(PVC)全流程生产调度问题, 包括从电石生产、盐水电解到氯乙烯(VCM)聚合产品出厂各环节, 其中电石生产和VCM聚合是间歇过程, 其他生产环节是连续过程, 是一个混杂系统调度问题。本文针对过程特性对该问题进行了合理假设, 以包括电耗、库存、产品型号切换、交货延迟等的成本最小为目标, 建立了基于离散时间表示的混合整数线性规划(MILP)调度优化模型, 并针对一个案例进行了调度优化求解和分析, 验证了模型的可行性。     

Dielectric relaxation and optical properties of polyvinyl chloride/lead monoxide nanocomposites

Sol–gel synthesized lead monoxide (PbO) nanoparticles were mixed with polyvinyl chloride (PVC). The dielectric characteristics of PVC/PbO nancomposite films were studied in the temperature range 303–408 K and frequency range 30 kHz–3 MHz. There is a sharp increase in the dielectric constant (ε′), after the glass transition temperature. According to the temperature and frequency dependence of the dielectric loss modulus (M″), the observed α_a‐relaxation peak is due to the micro‐Brownian motion of the polymer main chains. The behavior of σ_ac (f) for the composite films indicate that the homogenous distribution of PbO nanoparticles allows the formation of conductive three‐dimensional networks throughout the nanocomposite films which assisting the charge carriers to hop from conducting clusters to neighbors. The influences of PbO content on the direct optical band gap and the refractive index of the films are also discussed and compared with those of previous studies of PVC composites. POLYM. COMPOS., 34:2031–2039, 2013. © 2013 Society of Plastics Engineers     

聚氯乙烯/氯化聚氯乙烯合金的性能研究

选择氯化聚氯乙烯(CPVC)、聚氯乙烯(PVC)为主体材料,研究了PVC/CPVC共混比、填料品种及用量等对PVC/CPVC合金体系力学性能的影响,同时利用扫描电镜对PVC/CPVC合金的微观结构进行了分析。结果表明,CPVC在加工过程中易发生脱HCl反应,PVC常用的铅盐稳定剂、有机锡类稳定剂均适于CPVC体系,且铅盐稳定剂的稳定效果要优于有机锡类稳定剂。当m(PVC)∶m(CPVC)从100∶0向70∶30变化时,随着CPVC含量的增多,PVC/CPVC二元合金体系的屈服强度、拉伸强度、弯曲强度、热变形温度(最大弯曲正应力分别为1.82 MPa和0.45 MPa)等均呈递增趋势,而冲击强度、断裂伸长率出现递减趋势。在填料用量为5份时,PVC/CPVC合金体系的力学性能以选用活性碳酸钙(CaCO3)为最佳。随着活性CaCO3用量的增加,PVC/CPVC合金的拉伸强度、弯曲强度、断裂伸长率呈先上升后下降的趋势。活性CaCO3用量的变化对冲击强度几乎无影响。当活性CaCO3用量超过10份时,PVC/CPVC合金的热变形温度上升。     

Use of polyvinyl alcohol in the manufacture of polyvinyl chloride

The stabiliser used in the suspension polymerisation of vinylchloride influences greatly the quality of the resulting polyvinyl chloride, in particle size and distribution, and the absorption rate of plasticiser, etc. The relationship between the manufacturing conditions of polyvinylalcohol (PV-OH) and its dispersing power was studied using vinyl acetate and trichloro-ethylene in place of vinyl chloride monomer. It was found that the dispersing power increased with greater the blocklike distribution of the intramolecular residual acetyl group and uneven distribution of the intermolecular residual acetyl groups of PV-OH. When such PV-OH was used in suspension polymerisation of vinyl-chloride monomer, good quality polyvinylchloride was obtained. PV-OH with such characteristics is preferable as stabiliser for the suspension polymerisation of vinyl chloride monomer.     

丁腈橡胶/聚氯乙烯共混胶

探讨了丁腈橡胶(NBR)中的结合丙烯腈质量分数、NBR／聚氯乙烯(PVC)(质量比,下同)、增塑剂邻苯二甲酸二辛酯(DOP)用量、PVC聚合度对NBR／PVC共混胶性能的影响,研究了NBR／低聚合度PVC共混胶的力学性能及加工流动性能。结果表明,随着NBR中结合丙烯腈质量分数的增加,NBR／PVC共混胶的耐油性能明显增强,力学性能也相应有所改善;NBR／PVC为80／20～60／40时．NBR／PVC共混胶的综合性能较好;DOP用量对NBR／PVC共混胶性能的影响不大;聚合度为700的PVC更适合于生产NBR／PVC共混胶,其力学性能、加工流动性能、耐老化性能与德国Bayer公司生产的牌号为Perbunan NT／VC3470B的NBR／PVC共混胶相当。     

聚氯乙烯生产中的氯化氢循环回收技术及应用

简述我国聚氯乙烯(PVC)生产高速发展形势及尚存问题,指出传统氯化氢回收技术的弊病所在,阐明以组合塔为核心设备的氯化氢循环回收技术及其优越性,介绍组合塔及其制作技术发展的各项措施,简要回顾以新技术替代传统技术从粗氯乙烯气体中回收氯化氢的10年改革进程、效果和在国内17个省的37套装置中的应用概况。     

基质增塑型吸水膨胀聚氯乙烯/氯化聚乙烯热塑性硫化胶的形态与性能

以交联聚丙烯酸钠( CPNaAA) 作为吸水材料,采用动态硫化法制备了聚氯乙烯( PVC) /氯化聚乙烯( CM) 共混型热塑性硫化胶( TPV) ,考察了基质PVC 的增塑对TPV 力学性能、微观形态、吸水性能及动态黏弹性能的影响。结果表明,在PVC 中添加邻苯二甲酸二辛酯增塑后,PVC/CPNaAA/CM TPV的拉伸强度、撕裂强度和硬度下降,但扯断伸长率明显增大; 基质的增塑使得PVC/CPNaAA/CM TPV 的吸水性能获得明显改善,且当基质PVC 中邻苯二甲酸二辛酯的用量为60 份( 质量) 时,TPV 在蒸馏水中浸泡200 h 的吸水率可达2 100%; 在应变扫描模式下,PVC/CPNaAA/CM TPV 出现了明显的Payne 效应,且随着基质增塑程度的提高,体系的Payne 效应有所减弱。     

Properties of chlorinated polyvinyl chloride

By chlorination of polyvinyl chloride in a water suspension, a number of samples of chlorinated polyvinyl chloride of varied chlorine content were prepared. The density, the temperature dependence of the dynamic modulus G' and the loss factor tg δ, as well as some mechanical properties of these samples were measured. The structure of the chlorinated PVC is discussed and the assumption expressed that the secondary maximum at ? 10°C corresponds to the movements of the short chain interceptions of poly (1,2-dichloroethylene). The tensile strength and flexural strength is growing linearly with the chlorine content. The impact strength from 65% Cl on is violently decreasing. By its behaviour, chlorinated polyvinyl chloride resembles a random copolymer of vinyl chloride and 1,2-dichloroethylene.     

本体法聚氯乙烯的加工

介绍了本体法聚氯乙烯的加工工艺。该工艺完全可以采用悬浮法PVC的加工装置进行加工。而且加工容易、产品质量好、成本低、效益显著。     

氯化聚氯乙烯树脂综述

介绍了氯化聚氯乙烯树脂(CPVC)的性能、应用领域、生产和使用情况,分析了国内外CPVC树脂的性能差距及缩小其差距应采取的措施.     

Thermal relaxation of polyvinyl alcohol fibre

Conclusions 1. The physical, mechanical and physicochemical properties of industrial Vinol yarns, obtained by thermal relaxation with a specified shrinkage, have been studied.2. The nature of the elongation change in yarns during thermal relaxation with a specified degree of shrinkage is explained by the fact that, with an increase in the degree of shrinkage, the order along the axis decreases and across the axis is increased.3. The possibility has been demonstrated of preparing high-strength Vinol yarns with adequate tensile strength and elongation.Leningrad Branch of the All-Union Scientific Research Institute for Man-Made Fibres. Translated from Khimicheskie Volokna, No. 2, pp. 51–53, March–April, 1969.     

我国聚氯乙烯工业的又一个十年

回顾了1984年迄今我国聚氯乙烯工业的发展概况和技术进展,并与国外水平对比,提出了一些建议。     

Synergism in thermal stabilization of polyvinyl chloride

Plasticized polyvinyl chloride was thermally stabilized by barium, cadmium, and zinc laurates, epoxidized soybean oil, and monoalkyl diaryl phosphite, and by combinations of these stabilizers. Of 26 possible combinations, 18 showed some improvement, 8 showed useful improvement, 7 showed marked improvement, and 3 systems were outstanding. Of the 26 combinations, 10 showed distinct synergism, based mainly upon combinations of Group II-B metals with Group II-A metals, “secondary” stabilizers, or both. Combinations of Group II-B metals with “secondary” stabilizers were particularly interesting and promising.     

Thermoplastic elastomers from NBR and polyvinyl chloride

This paper will discuss recently developed technology that demonstrates the effectiveness of a thermoplastic polyvinyl chloride/nitrile rubber alloy versus commercially available thermoplastic elastomers and conventionally cured rubbers. Compounding variations, mixing and processing of thermoplastic elastomers such as low temperature properties, compression set, heat resistance, flex properties, and oil and fuel resistance will be examined. Compounding variations of the PVC/NBR allows will be explored to show how recipe changes can affect these important properties.     

氯化聚氯乙烯生产与应用

介绍氯化聚氯乙烯生产方法,应用与市场,并对氯化聚氯乙烯的发展前景进行评述与展望。     

Thermal decomposition products of polyvinyl chloride

When plastics are involved in a fire they may yield toxic decomposition products. Some quantitative data on the decomposition products of plastics are available in the literature, but it is difficult to assess the danger from the different amounts of various products because of the absence of a suitable method of evaluation. The authors have proposed a method of evaluation based on pyrolysis followed by gas chromatographic analysis and have used it to assess toxicity from various thermal decomposition products of polyvinyl chloride. Hydrogen chloride was found to be the main toxic decomposition product.     

Processing aids for chlorinated polyvinyl chloride

Comparative studies of melt processability showed that chlorinated polyvinyl chloride (CPVC) had low melt index and high Brabender melt temperature and torque, as compared with conventional rigid polyvinyl chloride (PVC). Of 3 processing aids at 10 percent concentration, triphenyl phosphate increased melt index 30-fold, fusion rate 10-fold, melt temperature 20°C, and torque 31 percent in CPVC. Two other processing aids, an acrylic and a styrene/acrylonitrile copolymer, were less effective. Improvements in PVC were less dramatic than in CPVC. Overall, use of processing aids made CPVC processability equal or even superior to conventional rigid PVC.