PVC消光树脂的应用研究

本研究了PVC消光树脂的结构特点及其对材料加工性能、物理机械性能的影响，结果表明：消光树脂使材料的加工难度增加．而通过加入ACR加工助剂，能有效改善PVC消光树脂的加工性能；随着消光树脂用量的增加．材料的拉伸强度略有下降，断裂伸长率无明显变化；消光树脂对材料的电性能影响不大。同时，进行了消光树脂挤出、注塑、压延制品方面的应用性研究。结果表明：消光树脂对注射制品的光泽度改变不大，而对挤出、压延制品有较好的消光效果。     

阻隔性尼龙树脂研制进展

本文综述了国外阻隔尼龙树脂的研制进展，阻隔尼龙树脂的阻隔性能，加工性能及其应用。     

浅谈悬浮法VPC树脂的颗粒结构对其加工性能的影响

详细分析了PVC树脂外皮膜结构，粒径大小及分布，表观密度，孔隙率与增塑剂吸收量对树脂加工性能的影响，提出了PVC树脂的不同颗粒结构适于不同的加工方法和用途。     

PVC混合料加工性能的研究

介绍了国内外PVC混合料的概况，从增韧改性的机理，加工流变理论及颗粒结构等方面论证了影响PVC混合料加工性能的各种因素。并通过实验分析数据来比较沧井化工树脂产品与国外大型企业同类产品在加工性能上的差距，结果表明国产沧井化工树脂的加工性能完全可与国外大型企业同类产品相媲美。     

偏氯乙烯-氯乙烯悬浮共聚树脂的加工性能研究

研究了偏氯乙烯(VDC)-氯乙烯(VC)悬浮共聚树脂的加工流变性和热稳定性。结果表明：增加共聚树脂中VC单元的含量，可改善树脂的流变性能，而对热稳定性几乎无影响；提高树脂的相对分子质量导致树脂流变性能降低；环氧大豆油(ESO)、乙酰基柠檬酸三丁酯(ATBC)助剂能改善树脂的加工流变性，其中ESO兼有热稳定剂作用。该共聚树脂的流变特性与日本树脂相近。     

用树脂分散体硫化的IIR轮胎硫化胶囊

重点讨论了树脂硫化的ＩＩＲ轮胎硫化胶囊。在树脂的稳定性、树脂的效率、胶料的加工性能及最后的硫化胶性能方面，粉末状未预分散和预分散硫化树脂之间是有差别的。还讨论了某些加工助剂对混炼特性、批料之间的一致性以及胶料流动性的影响，也探讨了加料顺序以及混炼条件对硫化胶性能的影响。     

绿色建材专用PVC树脂R—1000的特性及其加工和应用

本简述了R-1000树脂的合成，并从树脂的质量指标，颗粒特性，加工性能，VC脱吸速率及VC残留等方面对R-1000产品与国外同类样品进行分析对比，分析结果表明R-1000树脂的性能已达到国际水平，充分体现出其用于挤出成型硬制品的优势，经市场加工应用，本公司开发的R-1000树脂受到一些用户欢迎和认可。     

不可忽视的PVC树脂相关因素

论述了PVC树脂的外观与加工性能之间的关系,电石法PVC树脂不同批号间性能的差异性,PVC树脂颗粒形态与加工性能之间的关系,PVC树脂的"鱼眼"对型材表面质量的影响.     

S-1000A新型PVC专用树脂

齐鲁石化股份有限公司树脂研究所开发的PVC树脂S-1000A新产品通过集团公司鉴定。该专用树脂具有适宜的聚合度和良好的颗粒形态，塑化时间短，流动性能好，加工性能优良，达到国外同类产品的先进水平。通过工艺稳定性调整，跟踪检测数据显示，性能完全达到预期要求。该专用树脂在型材和管材应用中有明显的优势，很好地满足了引进高速型材、管材加工设备的技术要求，生产的型材和管材完全满足相关国家标准的指标要求。     

聚乙烯树脂

LL4004EL是一种线性低密度聚乙烯（LLDPE）树脂，用于低压供电电缆绝缘。据说，该树脂可达到交联速度与易于加工性能之间的良好平衡，价格有竞争力。由于优化了防老剂，改善了聚合物的性能，该树脂特别适用预硅烷交联工艺，因为对该工艺来说，交联速度和加工性是关键因素。LL4004EL树脂已经过两年的现场实验，适于在一步和两步加工工艺中使用。     

超低聚合度PVC树脂研制过程中巯基乙醇添加方式探讨

通过具体的试验数据阐述了巯基乙醇加料方式对PVC树脂主要性能指标（如聚合度等）的影响。结果表明：在适当提高聚合温度（61～64℃）的条件下，分散剂用量0．20％，巯基乙醇用量0．13％时。采取在氯乙烯聚合反应开始时一次流加巯基乙醇3h的方式，所生产的聚合度为400的超低聚合度PVC树脂质量最佳。     

超低聚合度PVC树脂制备及特性

$ 简述了超低PVC树脂制备要点,探讨了物性指标和特性。发现超低PVC树脂凝胶化温度低,加工流动性好,熔融因数(F)值高。制品表面光洁度、透明度、热稳定性和阻燃性优良;与其他高分子材料有较好相容性和“分子内增塑”作用,共混改性后替代ABS等工程塑料,能降低成本,有较高实用价值和经济效益。     

The influence of two‐stage variable temperature suspension polymerization on polyvinyl chloride resin: The molecular chain segment structure and thermal stability

The suspension polymerization of polyvinyl chloride (PVC) was carried out at two different constant temperature conditions (52.5°C and 57.5°C) and at two‐stage variable temperature conditions (52.5–57.5°C). The molecular weight and molecular weight distribution were characterized by gel permeation chromatography (GPC). The unstable chlorine content, total double bond content, and conjugated diene content were explored via phenol substitution, catalytic bromine addition, and ultraviolet–visible spectroscopy (UV–Vis). pH meter and thermogravimetric analyzer (TGA) were used for the determination of the thermal stability. According to the results, due to the gradual consumption of the impurities and the effect of the local high temperature in the early stage of polymerization, which caused more molecular chain‐transfer and more structural defects, a large number of oligomers generated. A rapid increase in the molecular weight could be found until the conversion was close to 23%. A lower temperature should be conducive to reducing the structural defects in molecular segments. Based on these observations, we applied two‐stage variable temperature polymerization and compared the PVC resin at a similar molecular weight at a constant temperature of 56°C. The PVC resin produced by the two‐stage variable temperature polymerization process obtained a similar Polydispersity index (PDI), reduced the unstable chlorine content by 15.11%, reduced the total double bond structure content by 8.81%, reduced the conjugated diene structure content by 13.86%, and increased the thermal stability time by 13.91%, thereby improving the thermal stability of the PVC resin. J. VINYL ADDIT. TECHNOL., 25:E80–E87, 2019. © 2018 Society of Plastics Engineers     

马来酸酐接枝改性氯化聚氯乙烯的制备及其在PVC中的应用

采用固相法制备马来酸酐接枝氯化聚氯乙烯(CPVC-g-MAH),得到了接枝率达2.91 %的CPVC-g-MAH,并对其进行了性能测试,探讨了聚氯乙烯(PVC)/CPVC-g-MAH共混物的冲击性能和加工性能,与PVC/氯化聚氯乙烯(CPVC)共混物进行对比以观察改性效果。结果表明,CPVC-g-MAH的热性能较CPVC有较大提高;PVC/CPVC-g-MAH共混物的冲击性能比PVC/CPVC共混物有所提高,而平衡转矩有所降低,说明CPVC-g-MAH相比于CPVC对PVC共混物加工性能改善效果更加明显。     

Thermal characterization of poly(vinyl chloride) samples prepared by living radical polymerization: Comparison with poly(vinyl chloride) prepared by free radical polymerization

Poly(vinyl chloride) (PVC) samples were synthesized by a living radical polymerization (LRP) method and compared with commercial PVC prepared by the conventional free radical polymerization (FRP). The differences were assessed, for the first time, in terms of viscosimetry parameters and thermal analysis. The LRP method used to prepare the PVC‐LRP samples is the only one available to obtain this polymer free of structural defects, being of commercial interest in a view of preparing a new generation of PVC‐based polymer with outstanding performance. The polymerization temperature selected (35°C) to prepare the LRP samples is currently used in the industry to prepare PVC‐FRP grades with moderate to high molecular weight. Since the thermal stability is a direct consequence of the polymer structure, this study is of vital importance to understand the potential of new PVC‐LRP. The thermoanalytical measurements demonstrate an enhanced thermal stability of PVC‐LRP when compared with its FRP counterpart. The PVC‐LRP sample with very low molecular weight reveals a higher thermal stability than the most stable PVC‐FRP sample. It is the first report dealing with thermal analysis of PVC prepared by LRP. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

高聚合度聚氯乙烯的加工性能

本文对高聚合度聚氯乙烯(H-PVC)的发展及其优异的物理机械性能作了简要介绍;着重分析了H-PVC的加工性能和表征方法,并讨论了分子特性和颗料特性及加工组成、加工条件对加工性能的影响,提出了改进H-PVC加工性能的方法。     

分子量分布对低密度聚乙烯光氧老化特性的影响

采用衰减全反射红外光谱技术（ATR-FTIR）、热重分析法（TG）、凝胶渗透色谱（GPC）、扫描电子显微镜（SEM）和力学试验比较研究了不同分子量分布指数低密度聚乙烯（LDPE）的光氧老化特性,分析了分子量分布对LDPE化学结构、热稳定性、平均分子量、表面微观形貌和力学性能的影响规律。结果表明分子量分布越宽,LDPE不饱和度增长越剧烈,支化作用增长越显著;分子量分布越窄,羰基指数增长越快;分子量分布对于分子结构的断链行为并无影响。分子量分布指数越大,LDPE起始热分解温度和失重5%对应温度下降更快,热稳定性更容易变差,平均分子量下降更多,表面微观形貌老化现象越严重;弯曲强度和冲击强度受影响更显著,指数为6.0的LDPE老化24 d冲击强度就已丧失。分析认为,分子量越大、分布越窄表明分子链越长、短分子链越少,与氧接触而产生自由基的概率也越小,因此聚乙烯分子量分布越宽,材料越容易老化。     

Controlled free‐radical polymerization of vinyl chloride

Owing to the importance of poly(vinyl chloride) (PVC) as the second‐largest plastic in volume after the polyolefins and above styrene polymers, the control of the free‐radical polymerization of vinyl chloride (VC) is of high industrial and academic interest. But still the term “controlled” polymerization is not yet clearly defined. Often it is used for quasi‐living polymerizations with equilibrium reactions in the initiation and/or termination step or for the control of the molecular weight distribution (MWD), but it can also be applied to several structural aspects such as stereochemistry, branching, or special technical properties. In the present article, the control of chain growth and chain transfer is discussed. It has been well known for many years that the propagation step in the VC polymerization is terminated to a large degree by the rather frequent and temperature‐dependent chain transfer of the growing macromolecules to the monomer. Therefore, the degree of polymerization is strongly governed by the polymerization temperature. However, this transfer step does not result in a controlled or a narrow MWD. By means of free‐radical nitroxide‐mediated polymerization of VC in suspension, PVC with a narrower MWD can be obtained also at higher polymerization temperatures. The resulting PVC with nitroxide end groups can act as a macro‐initiator for various monomers, resulting in two‐block copolymers, which are, e.g., interesting compatibilizers in blends with PVC. J. VINYL ADDIT. TECHNOL., 11:86–90, 2005. © 2005 Society of Plastics Engineers     

Investigation of the effects of nonisothermal suspension polymerization of vinyl chloride on the fusion and degradation behavior of poly(vinyl chloride)

Thermal stability of poly(vinyl chloride) (PVC) samples polymerized under a temperature trajectory was studied from the point of view of morphological and microstructural characteristics. The results are compared with those of the PVC samples obtained by polymerization at constant temperature having the same K value. The Brabender^® plastograph data indicated that the final PVC synthesized with the temperature trajectory showed lower fusion time and higher thermal stability time. The nonisothermal condition also increased the degree of fusion of the final PVC resin, reflecting lower temperature/time required to process it. It was found that the thermal stability of nonisothermally produced PVC as characterized by dehydrochlorination rate decreased (improved) with the increasing monomer conversion until a minimum value was reached that corresponded to the conversion at the pressure drop. However, the dehydrochlorination rate remains almost constant with conversion for an isothermal grade PVC resin. Although the evolution of the number of internal double bonds as well as extent of discoloration of PVC with conversion shows a decreasing trend, the labile chlorine concentration exhibits a maximum at early conversion. The reason for the former can be explained by the temperature dependence of reactions forming defect structures, which are kinetically controlled and thus favored at higher temperatures. The latter, however, can be explained because of the increasing importance of transfer reactions to polymer with increasing polymer concentration. Finally, the results from differential thermogravimetry verify an improvement in thermal stability of the final PVC prepared by using a temperature trajectory during vinyl chloride monomer suspension polymerization. J. VINYL ADDIT. TECHNOL., 23:259–266, 2017. © 2015 Society of Plastics Engineers