分散剂对PVC树脂性能的影响

研究了采用进口分散剂替代国产分散剂制备的PVC树脂的性能。结果表明:替代后PVC树脂的老化白度提高,颗粒形态变得更为规整,树脂颗粒内部孔隙数量明显增多,增塑剂吸收时间缩短。加工应用试验表明:更换分散剂后,生产的制品具有较高的透光率、较低的黄色指数和雾度。     

PVC制品中形成“假鱼眼”的因素分析

通过测试聚氯乙烯(PVC)树脂的基本性能,剖析其颗粒内部结构,分析了PVC制品中形成"假鱼眼"的因素。结果表明:树脂颗粒分布较宽、质量平均粒径较大,易使制品形成"假鱼眼";树脂相对分子质量偏大也易使制品形成"假鱼眼";树脂颗粒皮层结构较紧密、颗粒内部孔隙分布不均匀以及孔隙率较低影响了增塑剂的吸收量及吸收时间,是造成PVC制品"假鱼眼"的内在因素。     

关于改进明胶分散体系PVC颗粒形态及其塑化性能的研究

以明胶作悬浮聚合分散剂的PVC,是一种吸收增塑剂速度较慢,吸收量较少和塑化加工性能较差的紧密型颗粒形态的树脂。以烷基芳香烃磺酸盐类表面活性剂可改造明胶体系,使之生产疏松型颗粒形态的PVC树脂。本文对于改进树脂颗粒形态的机理进行了分析和研究,对于影响明胶体系PVC颗粒形态有关因素的相互影响关系进行了方程式的理论推导。从而认识了树脂吸收增塑剂的量与树脂颗粒平均粒径p和烷基苯磺酸钠浓度C_s的X次方的乘积成正比,与聚合温度T的f次方乘积成反比。因而可以能动地控制明胶体系PVC的颗粒形态及其塑化加工性能。     

消光PVC树脂性能的影响因素

分析了聚合温度和交联剂种类对消光PVC树脂性能的影响,以及加工温度和增塑剂用量对制品光泽度的影响。讨论了消光PVC树脂和通用PVC树脂混合后的流变性能,发现二者平均聚合度越接近,混合物的加工性能越优异。     

颗粒特性对聚氯乙烯树脂基本性能的影响

研究了牌号为QS-800F的聚氯乙烯(PVC)树脂的颗粒形态及其粒径分布、颗粒微观结构对QS-800F树脂基本性能的影响,并与国内应用较好的同类型树脂进行了对比分析.结果表明,QS-800F树脂具有良好的颗粒形态,粒径分布适中,颗粒表皮多为不连续结构,颗粒内部孔隙率高,具有很高的增塑剂吸收值和较强的增塑剂吸收能力.     

提高聚氯乙烯树脂白度的TJ液工业化试验

悬浮法聚氯乙烯树脂的热老化白度是PVC树脂各项指标中非常重要的一项，是直接关系PVC树脂热稳定性的重要指标，对PvC树脂加工制品的色泽、抗老化性、使用寿命都有很大的影响。所以，了解并掌握影响PVC树脂老化白度的因素，对提高PVC树脂的耐老化性能具有重要的指导意义。     

浅谈悬浮法PVC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树脂的不同颗粒形态和结构适于不同的加工方法和用途     

XS型PVC树脂研制小结

目前:PVC树脂的颗粒形态分为棉球型与乓乒球型两种。乒乓球型树脂外观为紧密的透明的或不透明的乒乓球,加工不易塑化,制品鱼眼多,产品质量差,在国外这种型号树脂已被淘汰,而生产棉花球型树脂。棉球型树脂与乒乓球型树脂相比有很多优点:(1)加工时易于吸收增塑剂,加工性能好鱼眼少;(2)假比重轻,而颗粒表观多孔,物料便于用气力输送,能改善加工环境的铅尘量,并减轻劳动强度提高捏合效率;     

疏松型聚氯乙烯树脂的研究

一、前言由悬浮聚合方法得到的聚氯乙烯(以下简称PVC)树脂,从颗粒形态上分类基本上被分成两大类,即疏松型PVC树脂和紧密型PVC树脂。前者因具有疏松多孔,吸收增塑剂能力较强,在加工软制品时具有很好的加工性能,且制品质量也好(“鱼眼”少)等优点,所以国内外从事疏松型PVC的科技工作者都以极大的兴趣注意着生产疏松型PVC树脂的技术发展。氯乙烯(VC)悬浮聚合是个多相变化体系,同时随着反应的进行,釜内物料体积也在不断地缩小;特别在生产疏松型PVC时,髓着PVC树脂生成和不断增多,游离的水也会不断地减少。所以就整个反应过程而言,确是一个很复杂的过程。就现技术水平而     

S-1200型PVC树脂的开发及加工应用

通过降低聚合温度,调整分散剂、引发剂的用量及配比等措施,在23万t/a聚合装置上成功生产出了新牌号树脂——S-1200,其具有规整的颗粒形态,适宜的颗粒大小,集中的分子质量分布,较高的白度,较少的"鱼眼"数,较高的增塑剂吸收速率。实验室加工试验结果表明:S-1200树脂具有较好的透光率、雾度和黄色指数,具有良好的耐老化性能和力学性能。工业化加工应用结果表明:S-1200树脂设备适应能力强,无须改变配方和加工工艺,所生产的制品不仅满足质量要求,而且具有白度高、晶点少等优点。     

PVC表观密度、老化白度对物料流变性能的影响

选取不同表观密度、老化白度的PVC,用RM智能转矩流变仪及小型实验用塑料挤出机进行流变对比实验,考查PVC表观密度、老化白度指标对物料流变性能及加工性能的影响。     

A Study on Morphological Structure of Low Molecular Weight PVC Prepared by Vibromilling Degradation

The effects of vibromilling on particle size, crystalline structure, optical density, and the plasticizer absorption of poly(vinyl chloride) (PVC) were studied through Fourier-transform infrared spectroscopy, scanning electron microscopy and physical property tests. The experimental results show that the intensity of the FTIR absorption band at 635 cm^?1 of PVC becomes weaker and tends to disappear during vibromilling. The particle size of PVC is decreased, and the surface area and the amount of plasticizer absorption increase with increased vibromilling time. The low molecular weight PVC so prepared has lower crystallinity and glass transition temperature, and higher plasticizer absorption capacity; it should have good processability.     

Studies of molecular weight distribution,particle morphology,and rheological behavior of ultra-high molecular weight suspension PVC

In this paper, the particle characteristics and rheological behavior of ultra-high molecular weight PVC (UHMWPVC) produced in both Japan and mainland China were studied. The molecular weight and its distribution of UHMWPVC were measured by GPC. By means of a series of techniques such as SEM, the measurement of surface pore size, plasticizer absorption, and photographic analysis, the morphology and general characteristics of UHMWPVC particles were investigated. A model of particle structure was proposed. It was found that compared to general PVC, UHMWPVC resins are more porous, having better plasticizer absorption properties. Similarly, compared to UHMWPVC made in mainland China, UHMWPVC made in Japan possesses particle characteristics preferred in PVC processing. In the studies of rheological behavior, the programmed temperature Brabender torque rheometer was used to study and compare the melting process of UHMWPVC resins and their plasticized systems under the same shear stress. The capillary rheometer and Brabender extrusion-rheometer were applied to investigate the rheological and extrusion properties of the plasticized systems mentioned above. The results showed that in melting and extrusion process, the particle characteristics of UHMWPVC result in the easy breakage of particles and the formation of “molecular flow,” On the other hand, the high molecular weight is unfavorable to processing. Generally speaking, much more research work is needed to improve the flow properties of UHMWPVC.     

汽车用环保PVC电缆料的研制之一——PVC聚合度的选择

比较了S-1000型、S-1300型和P-2500型PVC树脂的物理性能、耐老化性、力学性能及其电缆料的性能,以及采用不同厂家的1000型PVC树脂生产的绝缘电线的外观质量。结果表明:①高聚合度PVC树脂在老化白度、耐热性、增塑剂吸收量、力学性能等方面都优于普通聚合度PVC树脂,且具有更好的耐老化性及更低的脆化温度;②从力学性能、绝缘性能方面考虑,高聚合度PVC树脂更适合生产电线电缆等软制品,但应注意其熔体流动性大幅下降。     

Particle configuration and properties of poly(vinyl chloride)/halloysite nanotubes nanocomposites via in situ suspension polymerization

Poly(vinyl chloride) (PVC)/halloysite nanotubes (HNTs) nanocomposites were synthesized by in situ suspension polymerization of vinyl chloride (VC) in the presence of HNTs. The microstructure, mean particle size, and cold plasticizer absorption (CPA) of these resins and the rheological property, mechanical properties and thermal properties of PVC/HNTs nanocomposites were investigated. The results show that the mean particle size, the degree of porosity, and the CPA of PVC resins decrease with the addition of HNTs. The plasticization time and the equilibrium torque of PVC/HNTs nanocomposites are found to be longer and higher than that for the neat PVC. HNTs are uniformly distributed in the PVC matrix and effective in toughening and stiffening PVC nanocomposites when the addition of HNTs is 4.0 wt% or less. The glass transition temperatures of the PVC/HNTs nanocomposites were nearly identical to that of pure PVC. POLYM. COMPOS., 35:856–863, 2014. © 2013 Society of Plastics Engineers     

QS-800F树脂的开发及应用研究

对引进西方化学公司技术生产QS-800F树脂的聚合工艺和聚合配方进行了优化,缩短了聚合时间,降低了平均聚合度,提高了转化率和老化白度,成功开发出性能优异的PVC新产品;分析研究了QS-800F树脂的性能,并进行了加工应用试验。结果表明,QS-800F树脂具有良好的加工性能和优异的光学性能,各项性能均满足相应产品的标准要求。     

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.     

聚氯乙烯树脂吸收增塑剂的影响因素

研究了不同聚合度聚氯乙烯树脂的增塑剂吸收量与吸收时间随聚合度变化规律。结果表明:聚氯乙烯树脂对增塑剂的吸收量随聚合度增大而增大;不同聚合工艺生产的聚氯乙烯树脂由于皮膜结构差异致使对增塑剂的吸收时间差异很大;同一工艺生产的聚合度相同的聚氯乙烯树脂,对增塑剂吸收时间长的塑化能力差。     

国产HPMC分散剂在127m3釜上生产PVC树脂的应用总结

上海氯碱化工股份有限公司在127m^3聚合釜中成功试用了国产HPMC分散剂,以替代价格昂贵的进口HPMC分散剂。共进行了50釜的应用试验,试生产了B、D、F三种牌号PVC树脂。通过分析B、D、F三种牌号PVC树脂的常规质量(如,表观密度、VCM残留量、“鱼眼”数及挥发分)、塑化性能、增塑剂吸收量及粒径分布,发现除了F牌号PVC树脂的平均粒径及粒径分布略微变宽、三目集中率略有偏低外,B、D牌号树脂的性能及F牌号树脂的其它性能均无明显变化。同时还指出,F牌号PVC树脂的粒径大小与分布可通过调整分散剂的用量来解决。     

ATM系列PVC高效加工助剂

介绍了大连天元精细化工有限公司研发的一种专利产品——超低玻璃化温度弹性体复合改性PVC高效加工助剂ATM,比较了ATM和ACR的加工性能和产品力学性能。结果表明,ATM系列产品与PVC相容性优异,加工性能极佳,适合PVC制品的高速挤出,能改善制品的白度和表面光洁度,抗老化性显著,综合力学性能优异。显微分析得知,ATM与传统ACR在结构上为同质异构核壳结构,但性价比占有明显优势。