PVC发泡助剂

一、概述聚氯乙烯(PVC)塑料是世界上产量最大的热塑性合成材料之一。其繁多的加工制品广泛地应用于工农业生产和日用品,其中颇大一部份是发泡PVC制品,具有良好的电绝缘、热绝缘性能,消声消震,价廉、质轻,尤其是泡沫人造革、地板革、墙纸、鞋底、海棉垫等,很受消费者的欢迎。为了制得泡孔均匀细密、手感柔和、表面光滑的发泡PVC制品,在PVC发泡时常用的发泡剂是偶氮二甲酰胺(AC)。在一定的温度下AC发生化学分解,产生多种气体。这些气     

我国硬质PVC低发泡挤出制品的发展概况

本文综述了我国硬质PVC低发泡挤出制品的现状和发展前景,分析了存在的问题,并提出了一些建议。     

硬质PVC发泡制品的配方设计

阐述了硬质PVC发泡制品配方中PVC树脂和热稳定剂、发泡剂、优泡剂、冲击改性剂、加工改性剂、填充剂、润滑剂及成核剂等助剂的选用原则,介绍了生产优质硬质PVC发泡制品的基础配方。     

关于软质PVC发泡制品原材料的选用之浅见

本文叙述了软质PVC发泡制品的发泡机理,分析探讨了软质PVC发泡制品的各种原材料,得出了各种原材料的选用原则。     

2014年硬质PVC发泡制品行业状况及发展建议

介绍了2014年硬质PVC发泡制品行业的发展状况,详细分析了下游房地产行业的发展趋势,重点介绍了硬质PVC发泡实心板、硬质PVC发泡中空格子板、室内外装饰用硬质PVC发泡材料等主要产品的市场情况,并对行业的发展提出了建议。     

PVC发泡人造革泡孔质量研究

以理论分析和实践经验论述了提高ＰＶＣ发泡人造革泡孔质量的实质。     

成核剂对软质PVC鞋底发泡材料的影响

讨论了4种成核剂二氧化钛、微细重质碳酸钙、纳米级超细碳酸钙和滑石粉对软质PVC鞋底发泡材料性能的影响。结果表明:成核剂TiO2、微细重质碳酸钙、纳米级超细碳酸钙能有效降低材料的密度,而滑石粉增大了材料的密度;成核剂TiO2,微细重质碳酸钙,纳米级超细碳酸钙用量分别为2phr、2phr、1phr时,获得的鞋底发泡材料性能优异;粒径越小的成核剂,获得材料的密度越小、泡孔越均匀细密。     

软质PVC发泡材料的研究

采用化学发泡一步法模压成型制备了软质PVC发泡材料,研究了发泡剂、泡孔成核剂、改性剂等主要助剂用量对软质PVC发泡材料密度、泡孔结构以及力学性能的影响,并进行了软质PVC发泡材料的配方筛选.结果表明加入吸热发泡剂N能提高发泡体系的发泡效果,降低材料的密度,改善材料的力学性能,当发泡剂AC用量为2份,用量为0.6份时,材料的综合性能优异;当成核剂用量为1份时,体系发泡效果较好;加入粉末NBR不仅能提高发泡材料的断裂伸长率和柔韧性,还可降低发泡材料密度,改善泡孔结构;当NBR用量为20份时,发泡材料密度达到0.44 g/cm3,力学性能优异.     

PVC/木粉发泡制品温度分布的研究

研究了环境温度、结皮层对PVC/木粉发泡制品温度分布的影响,并测试该温度分布下,制品力学性能的变化。试验结果表明:上面的环境温度对制品温度的分布影响较大;制品表面结皮层能够加快热量的传导,从而使得制品温度分布上升;制品温度分布对力学性能有影响。通过公式拟合,可以计算得到在表面环境温度为90℃,底面环境温度为40℃下,制品的弯曲模量;该计算值与实测值相当。     

硬质PVC发泡制品专委会2009年年会召开

本刊安徽铜陵消息（2009年9月15日）中国塑协硬质PVC发泡制品专业委员会2009年年会暨技术交流会于9月14～15习在安徽省铜陵市逸顿宾馆举行。会议由中国塑协硬质PVC发泡制品专委会主办,铜陵市耐科科技有限公司及河北精信集团承办,中国塑协新材料研究开发工作委员会作为支持单位。中国塑料加工工业协会廖正品会长、铜陵市人民政府崔玉奇副市长、     

New ultra high molecular weight acrylic processing aids for rigid PVC foaming

Foaming of rigid polyvinyl chloride (PVC) is studied as a function of high molecular weight acrylic processing aids. The industrial process to evaluate quality of foam is discussed in detail. The role of acrylic processing aids to improve melt strength and hence foaming of PVC is explained. It is demonstrated that increase in molecular weight of acrylic processing aids increases its effectiveness. It is found that ultra-high molecular weight processing aids is 25%–30% more efficient than relatively lower, but still high, molecular weight acrylic processing aids. The higher molecular weight processing aids provided comparable foaming performance at lower loading levels. Foaming reduced the density of PVC compounds to 0.32–0.34 g/cm³. More than 1000% expansion is achieved in the melt extrusion process using a chemical blowing agent. Fusion characteristics are also studied. Fusion times for initial fusion peaks are in the range of 42–44 s while the fusion times of the second fusion peaks are in the range of 74–94 s. The higher molecular weight processing aids maintained fusion characteristics of PVC compounds, warranting no significant changes in commercial process.     

物理发泡型PVC泡沫的研究

探讨了PVC浆料黏度、混合器搅拌速度对PVC开孔泡沫发泡成型行为的影响,结果表明:PVC浆料黏度控制在0.265 Pa·s以上、混合器搅拌速度控制在1250 r/min为宜.     

可连续生产的物理发泡法可熔接PVC泡沫的研制

以PVC树脂为主料,添加表面活性剂、阻燃剂、稳定剂等助剂,用R 22作为物理发泡剂,研制了可连续生产的物理发泡法PVC泡沫,探讨了发泡剂用量、表面活性剂用量、射频仪电压对泡沫性能的影响。结果表明:表面活性剂用量增加,泡沫密度减小,拉伸强度降低;微波箱中电压变化,对PVC泡沫的影响没规律性,但有最佳值(6.0 kV);同时,电压增加,泡沫明显变黄;发泡剂R 22用量增加,泡沫密度减小,拉伸强度降低。     

Effects of the properties of blowing agents on the processing and performance of extruded starch acetate

The extrusion of polysaccharide‐based polymers, such as starch acetate, is quite different from that of ordinary synthetic polymers. To understand how the physiochemical properties of blowing agents affect plasticization and expansion processes, starch acetate was extruded with water, ethanol, and ethyl acetate. The studied properties and factors were the evaporation rate, surface tension, boiling point, solubility index, latent heat of vaporization of blowing agents, extrusion temperature, and nucleating‐ and blowing‐agent concentrations. The properties of the blowing agents and operating conditions affected the solubility of the matrix polymer, the nucleation process, and cell growth, which affected the foam density and specific volume. A high temperature increased the cell density and specific volume when water and ethanol were used because a high temperature increased the solubility of starch acetate in water and ethanol and promoted nucleation. Ethyl acetate already had high solvency to starch acetate and a high evaporation rate. A high temperature reduced the melting strength, thereby reducing the cell density and specific volume. Water evaporation was greater, despite a high latent heat of evaporation (hr) and boiling point, than the average volumes of ethanol and ethyl acetate that evaporated. The blowing‐agent efficiency was a function of the solvency, blowing‐agent evaporation rate, and operating conditions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1880–1890, 2005     

Soft PVC foams: Study of the gelation,fusion, and foaming processes. I. Phthalate ester plasticizers

The use of foamed plastics gains more and more interest every day. Flexible poly(vinyl chloride) (PVC) foams have excellent mechanical properties and low price, thus their application is extensive. Foams are produced from plastisols, which are based on the suspension of the PVC resin in a plasticizer. Phthalates are the most used plasticizers in flexible PVC foam formation. In this study, we have studied the influence of the phthalate ester‐type plasticizers on the foaming process and the quality of the foams obtained from the corresponding plastisols. For the plastisols prepared with the nine phthalate plasticizers considered, we have studied and discussed the complex and extensional viscosities; the thermal behavior (DSC) including the decomposition of the chemical blowing agent, and the foam production by rotational molding. In addition, we have characterized the foams obtained by thermomechanical analysis, density, and bubble size distribution. As expected, clear correlations have been obtained between the molecular weight and structure of the plasticizer with the rheological behavior of the plastisols. The knowledge of the gelation and fusion processes and evolution of the extensional viscosity of the plastisols combined with the study of the thermal decomposition of the blowing agent in each plastisol allows for better understanding of the complex dynamic behavior of these foaming systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚氯乙烯加工助剂ACR—I的试制

介绍了ACR—1的合成方法,考察了其反应最佳条件,并就其加工性能与抗冲性能与国内外同类产品进行了对比.     

悬浮法聚氯乙烯生产用防粘釜剂的进展

对悬浮法生产聚氯乙烯树脂聚合过程的粘釜和防粘机理进行了分析 ,介绍了目前国内外防粘釜剂的研究及应用情况 ,有助于全面了解悬浮法聚氯乙烯生产用防粘釜剂的发展历史及现状。     

Fundamental foaming mechanisms governing the volume expansion of extruded polypropylene foams

This article describes the fundamental foaming mechanisms that governed the volume expansion behavior of extruded polypropylene (PP) foams. A careful analysis of extended experimental results indicated that the final volume expansion ratio of the extruded PP foams blown with butane was governed by either the loss of the blowing agent or the crystallization of the polymer matrix. A charge coupling device (CCD) camera was installed at the die exit to carefully monitor the shape of the extruded PP foams. The CCD images were analyzed to illustrate both mechanisms, gas loss and crystallization, during foaming at various temperatures, and the maximum expansion ratio was achieved when the governing mechanism was changed from one to the other. In general, the gas loss mode was dominant at high temperatures and the crystallization mode was dominant at low temperatures. When the gas loss mode was dominant, the volume expansion ratio increased with decreasing temperature because of the reduced amount of gas lost. By contrast, when the crystallization mode was dominant, the expansion ratio increased with increasing temperature because of the delayed solidification of the polymer. The processing window variation with the butane concentration, the change in the temperature ranges for the two governing modes, and the sensitivity of melt temperature variations to the volume expansion ratio are discussed in detail on the basis of the obtained experimental results for both branched and linear PP materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2661–2668, 2004     

盐用聚氯乙烯吹塑塑苫薄膜的研制

介绍了采用吹塑法生产盐业专用聚氯乙烯(PVC)薄膜的研究。实践证明吹塑法生产盐用PVC薄膜技术可行,完全能满足盐业生产的需要。