PVC树脂白度的改进

在小试中改进聚合配方（单独使用EHP作为引发剂）的基础上,在现有生产工艺、不增加设备投资的情况下,确定了生产PVC－SG5型及PVC－SG2型树脂的方案。结果表明：改进后生产的PVC树脂白度达到80％以上,且生产中没有任何异常现象发生,这样可节约助剂成本14元／（t．PVC）,按3．5万t／a 计,每年可节约助剂成本40多万元。     

PVC树脂下游加工性能的实验室模拟评价

选取了不同批次的SG5型PVC树脂在实验室条件下模拟制品加工工艺进行了炼塑、流变性能及造粒试验,研究了配方调整对PVC树脂制品性能的影响,对PVC下游制品生产企业选择适合的PVC树脂原料提供指导,以保证PVC加工制品质量的稳定。     

卫生级SG8型PVC树脂的生产

介绍了采用108 m3聚合釜生产卫生级SG8型PVC树脂的工艺配方及关键工艺条件的控制指标。     

昊华宇航自主研发的缩短PVC聚合反应时间新技术通过鉴定

<正>昊华宇航公司自主研发的缩短SG3型PVC树脂聚合反应时间新技术,于2010年1月中旬通过河南省科技厅组织的成果鉴定。SG3型PVC树脂生产存在聚合反应温度低、周期长的问题,与SG5型PVC树脂相比,每釜生产时间增加60min。     

优化工艺 提高SG8型树脂产能

介绍了105 m~3聚合釜生产SG8型PVC树脂的生产工艺特点。通过优化生产工艺,从变更投料方式、调整工艺过程控制、提高生产能力等方面介绍了提高SG8型PVC树脂生产途径。     

改进PVC树脂质量 降低成本增效益

介绍了河南神马氯碱化工股份有限公司改进PVC树脂质量、降低成本采取的具体措施：(1)改进生产配方,改变分散剂、调粒剂、引发剂、pH值调节剂和终止剂;(2)采用塔式汽提装置脱除VCM,,实施上述措施后,PVC树脂的颗粒形态得到了改进,100gPVC—SG3树脂的增塑剂吸收量由平均24．25g提高到28．75g,100gPVC—SG5树脂的增塑剂吸收量由平均22．5g提高到26．5g;PVC树脂的老化白度提高约3％;节约资金32万多元/a,取得了可观的经济效益。     

高抗冲聚氯乙烯管件专用料的研制

介绍了一种采用超低聚合度聚氯乙烯树脂与SG5型聚氯乙烯树脂替代SG8型聚氯乙烯树脂研制高抗冲聚氯乙烯管件专用料的方法。最佳配方为：超低聚合度聚氯乙烯树脂与SG5型聚氯乙烯树脂质量份数比为20∶80,轻质碳酸钙用量35份,润滑体系中的PE蜡、硬脂酸用量0.6份,生产的管件制品拉伸强度和抗冲击性能较优,表面光泽度较好。     

电线电缆用耐热105℃软聚氯乙烯塑料的研制及生产

采用PVC—SG1树脂100份、增塑剂45份、稳定剂7份、改性剂5份、填料10份、硬脂酸0.3份,严格控制工艺条件,可生产出合格的电线电缆用耐热105℃软聚氯乙烯塑料。     

充电桩电缆用PVC护套料的开发

介绍了充电桩电缆用PVC护套料的开发难点,研究了PVC树脂和弹性体对护套料性能的影响,得到的适合实际生产的配方为:PVC树脂S-70 30份、PVC树脂S-80 70份、重质碳酸钙10份、稳定剂14份、高岭土12.5份、弹性体M 10份、增塑剂A 30份、增塑剂B 10份、增塑剂C 35份、润滑剂H 0.8份、润滑剂P 0.5份、光稳定剂1份、流变剂1.8份、阻燃剂7.5份。该PVC护套料在实际挤出生产过程中加工性能良好,产品外观光滑,产品性能达到充电桩电缆的技术要求。     

高型号PVC树脂聚合引发剂品种及特性的探讨

天津化工厂在生产PVC—SG7、SG8等高型号树脂时,用BNP与TMHP过氧化物复合体系代替ABVN氮类化合物引发剂。介绍了过氧化物引发剂及偶氮类引发剂的特性,指出过氧化物引发剂在氯乙烯中溶解性较好,可降低PVC树脂的“鱼眼”数,缩短反应周期,且该体系无毒,可用于生产环保型医药级PVC塑料制品。     

本体法与悬浮法PVC树脂生产工艺的比较及在管件生产中的优势

比较了本体法PVC7型树脂与悬浮法PVC-SG7型的生产工艺,介绍了本体法PVC树脂的质量、塑化性能和加工性能等在管件生产中的优势。     

PVC-U挤出时PVC指标对塑化性能的影响

对常用于PVC-U异型材生产的PVC-SG5树脂进行了指标分析,认为影响PVC塑化性能的重要指标为K值、粒径、分子质量分布、表观密度、孔隙率以及PVC树脂颗粒聚集和表面形态。     

A new process aid for melt compounding of PVC with ethylene copolymer resins

Ethylene copolymer resin (ECR) modifiers are solid, high molecular weight, permanent plasticizers for PVC. During the melt compounding step, the low melting ECR (m.p. ～50°C) melts first forming a relatively low viscosity phase in which the higher melting (Tg ～80°C) and more viscous PVC powder grains (～150 μm in diameter) are suspended. Under these conditions, it is sometimes difficult to get enough shear energy into the system to break down, or flux, all of the PVC grains into unagglomerated primary particles (～1 μm diameter). The remaining grains appear as gel-like heterogeneities, in the final blend, that can produce rough, pimpled extrudates with reduced physical properties. This paper describes the use of a new experimental process aid that significantly improves homogenization, during the melt compounding process, leading to improved product quality and/or production rates.     

引发剂BNP替代EHP在PVC-SG5树脂生产中的应用

研究了BNP作为引发剂等量替代EHP在PVC-SG5树脂生产中的应用,考察了生产的PVC-SG5树脂的质量(包括黏数、白度、增塑剂吸收量、表观密度、250 μm筛余物及"鱼眼"数等).     

‘Elasticisation’ and plasticisation of PVC with ethylene-vinyl acetate copolymers

Copolymers of ethylene and vinyl acetate (E-VA) of a certain composition can be used for the improvement of impact properties (elasticisation) of PVC as well as under certain conditions (grafting) for the preparation of flexible PVC (plasticisation). Products of interesting properties are prepared by blending E-VA (up to ～ 12%) with PVC or more advantageously by grafting vinyl chloride on special E-VA types. Graft copolymerisation by the suspension method allows the synthesis of E-VA/PVC systems in all ratios (up to 80% E-VA); these polymers are compatible over the whole range in contrast to the blends. Studies on the grafting efficiency of some monomers show that vinyl chloride can be grafted readily on E-VA. The grafting process is performed on a technical scale to give PVC types with E-VA contents up to 50%. Products with 6–8% E-VA should be classified as impact-modified suspension PVC. Flexible types (40–60% E-VA) have properties of flexible PVC with the plasticiser chemically incorporated, but may also be blended with unmodified PVC to give impact-improved formulations. The properties of the elasticised PVC (8% E-VA) mainly depend on the vinyl acetate (V-OAc) content of the E-VA and its molecular weight. Levapren® 450 P (45% V-OAc; mol. wt. ～ 100,000), a solution process copolymer, has good elasticising efficiency in blends and graft copolymers with PVC. PVC/E-VA products may be processed with or without addition of uncombined PVC into rigid or flexible PVC by the usual methods of PVC technology, e.g. extrusion, injection moulding, blow-moulding and calendering. Competitive modifiers, such as acrylonitrile-butadiene-styrene copolymers, methacrylate-butadiene-styrene copolymers, acrylates or chlorinated polyethylene, are compared with E-VA. Levapren® 450 P shows high efficiency as an impact modifier even in low concentration, giving good processability and ageing behaviour. Glass-clear high-impact PVC cannot be obtained by E-VA modification. Some electron microscopy studies to characterise the distribution of E-VA in the resin phase (PVC) are described; these showed the presence of a two-phase system.     

RPVC低密度自由发泡挤出板材生产工艺探讨

重点研究了RPVC低密度自由发泡板材配方中主要组成对挤出过程物料流变行为和发泡性能的影响,以500kg/m^3的发泡板材为例,设定、筛选出其生产配方：PVC树脂（聚合度800）100份;ADC发泡剂0.5份;Pb类稳定剂2.5－4.0份;高分子改性剂6-10份;润滑剂1－2份;消黄剂少许。简述了生产工艺流程和对加工湿度、机头压力、螺杆转速等工艺条件的控制。     

Relating chemical structure to poly(vinyl chloride) thermal stability

This paper deals with the main concepts of the modern theory of poly(vinyl chloride) (PVC) degradation, which embrace the key problems concerning the chemical structure and the content of anomalous groups in PVC, their influence on the thermal stability of polymer products, the kinetics of HCL elimination. In contrast to the universally recognized ～-chloroallyl activation of the process of PVC degradation, a conception of the prime role of oxygen-containing chloroallyl groups of type ～C(O)? CH?CH? CHCl～ (CAG) has been developed. It has been shown that PVC real macromolecules contain approximately 10^?4 mole/PVC mole oxygen-containing ～C(O)? CH?CH? CHCl～ groups determining PVC low thermal stability. It has been found that the monomer purity, the presence of oxygen in the reaction area, the temperature of vinyl chloride polymerization, etc., considerably affect CAG content in PVC macromolecules.     

浅谈PVC清洁生产

简要介绍了美国的道化学公司、杜邦公司,德国的巴斯夫公司开发的PVC清洁生产工艺技术,同时也介绍了我国开展PVC清洁生产的情况。指出：采用电石法生产PVC仍有发展空间,但必须从原材料、工艺技术的改进、环保治理技术及企业管理入手,实现综合利用,搞好PVC清洁生产,促进PVC行业的持续发展。     

煤制烯烃路线取代电石法路线生产PVC的机会与不确定性分析

通过对煤制烯烃路线PVC和传统电石法PVC的对比分析,认为前者在环保、能耗尤其是生产成本方面有较大的优势。但煤制烯烃路线PVC属于高耗水行业,而中国煤炭资源和水资源呈逆向分布,在煤炭资源丰富的西部地区普遍缺水;加上投资大、技术难度高、经济可靠性差等不确定因素的存在,煤制烯烃路线PVC要在国内全面取代电石法PVC还很难,只能作为未来有综合优势的氯碱企业所追求的目标。