氯乙烯-醋酸乙烯酯共聚糊树脂次级粒子特性研究

讨论氯乙烯-醋酸乙烯酯共聚乳液后处理工艺与树脂次级粒子特性间的关系。根据氯醋糊树脂性能特点,调整喷雾干燥器进出口温度,研究干燥工艺条件与树脂次级粒子结构及树脂增塑糊粘度间的关系,乳胶固含量对树脂次级粒子及糊粘度的影响规律,确定合适干燥工艺及乳液含固量,降低树脂糊粘度。对优化条件下制备的氯醋糊树脂颗粒特性、流变性能进行分析和对比,获得良好结果。     

PVC糊粘度影响因素的讨论

研究了PVC糊中部分主要组分对其糊粘度的影响，重点探讨了糊状PVC树脂种类、增塑剂的种类及用量、降粘剂的种类及用量等几大主要因素对PVC糊粘度的影响。实验结果表明，由于不同生产工艺使PVC糊树脂的初级粒子的粒径、粒子形态及粒子的分布形式不同，造成其成糊粘度及稳定性的差异。增塑剂的挥发性及溶剂化能力的差异会影响糊的粘度及稳定性。脂肪族烃类和可增塑类降粘剂的降粘机理的不同，会产生降粘效果的差异。     

从工艺角度初探降低PVC糊树脂粘度的几种途径

研究了初级粒子和次级粒子形态对PCV糊粘度的影响,阐明了形成理想初级粒子和次级粒子的原因和控制方法.     

PVC增塑糊黏度及其稳定性正交实验研究

采用L9（3^4）正交实验设计，研究PVC类型、填充剂粒径大小，硅油种类和用量多个因素对PVC增塑糊黏度及其稳定性的影响。实验结果表明：初级粒子粒径较大、表面较规则的微悬浮法糊树脂制得的增塑糊初始黏度最小，黏度稳定性较好；填充剂粒径大小与PVC增塑糊黏度成正比，粒径越大，糊初始黏度越大，粒径大小对糊的稳定性影响大致相同；100mPa·s硅油体系下增塑糊初始黏度较低，50mPa·s硅油体系下糊黏度稳定性较好；硅油加入0．6份时糊初始黏度较低，0．4份时糊黏度稳定性较好。     

旋转模塑用聚氯乙烯增塑糊的研究

一般来讲，影响旋转模塑用PVC增塑糊性能有五个因素，即PVC增塑糊的流变性能、糊粘度稳定性、脱气性能、凝胶化性能和塑化性能。作者通过对影响PVC增塑糊性能的这些因素进行深入研究，对确定PVC增塑糊所用原料种类和数量提供有益的参考。     

聚氯乙烯糊用掺混树脂对增塑糊及制品性能的影响

本文通过实验研究了掺混树脂对ＰＶＣ增塑糊的流变性能，凝胶化性能，糊粘度陈化稳定性及对增塑糊制品的力学性能、热性能、物理性能和发泡性能的影响，并分析了其影响作用的机理。     

PVC糊树脂颗粒特性对增塑糊陈化行为的影响

选用5种不同牌号的PVC糊树脂制备出增塑糊,研究了PVC糊树脂的颗粒特性对增塑糊陈化行为的影响。结果表明:①小粒子可填充在大粒子之间,从而降低增塑剂的填充量,自由增塑剂更多,成糊后初始黏度较低;②与紧密型糊树脂相比,松散型糊树脂的增塑糊黏度稳定性更好;③分子质量越大,真实密度越大,增塑糊黏度稳定性越好;④对于紧密型糊树脂,低黏度的增塑糊在陈化过程中大粒子会发生沉降,导致糊中粒子分布不均一。     

旋转模塑用聚氯乙烯增塑糊的研究

对影响ＰＶＣ增塑糊性能的五个因素：ＰＶＣ增塑糊的流变性能、糊粘度稳定性、脱气性能、凝胶化性能和塑化性能进行较为深入的研究；为确定ＰＶＣ增塑糊所用主要原料的种类和用量提供了有益的参考。     

旋转模塑用聚氯乙烯增塑糊粘度稳定性研究

PVC增塑糊粘度稳定性是影响糊制品加工工艺的重要因素。本文利用NDJ-1型旋转粘度计,通过测定糊粘度随时间的变化,对影响PVC增塑糊粘度稳定性的各种因素进行了较为详细的研究。     

干燥条件对树脂的颗粒形态和增塑糊流变行为影响的研究

种子乳液聚合法制得PVC胶乳,采用气流喷雾干燥器较系统地研究了相同性质的PVC胶乳,在不同干燥温度下,树脂次级粒子的形态结构及其增塑糊的流变行为。扫描电镜和透射电镜的观察表明,提高干燥温度和延长停留时间,会使次级粒子表面发生粘附性熔结,而导致增塑糊流变行为的改变。     

PVC paste rheology: Study of process dependencies

A plastisol is a dispersion (suspension) of fine particles of poly(vinyl chloride) with a plasticizer that is normally applied over a substrate, by spreading or coating, before the gelification and fusion into the final product. Because of the first step, the plastisol rheology study is a very important factor which has to be taken into consideration to determine and fine tune the process conditions. This work is concerned with the study of the rheology of plastisols from selected PVC samples produced by the emulsion process, correlating it with the particle size distribution and surface characteristics from the polymer's powder and modifications during the plastisol aging process. The results obtained show a significant influence of the original polymer properties in the viscosity aging and viscoelastic behaviour of the plastisol. First, a significant decrease in viscosity can be achieved by changing a particular surfactant during the polymerization step. Second, the type of particle aggregates present in the powder, can determine the evolution of the particle size in the plastisol which, in turn, correlates directly with the observed modifications in the aging and viscoelastic behavior. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

内热式惰性粒子流化床中膏状物料干燥模型

通过对惰性粒子流化床中膏状物料干燥机理的分析,得到了干燥时间及单位面积床层水分汽化量的数学计算式,可对干燥器的性能进行预测。采用带浸没加热管的惰性粒子流化床对膏状钛白物料进行干燥中试研究,采用气流式喷嘴将膏状物料分散成200～400μm的小液滴喷洒在惰性粒子表面进行干燥,探索了适宜的干燥条件,测定和确定了最佳的干燥工艺参数、操作参数和设备参数。结果表明:该干燥工艺能强化床内传热传质,促进高黏性膏糊状物料很好地分散,床层温度分布均匀,干燥器的操作弹性大,热量消耗低,干燥强度高,传热系数可达300W·m-2·K-1以上。     

PVC糊树脂颗粒形态研究

用扫描电镜结合粒度分析方法,研究了微悬浮法和种子乳液法PVC糊树脂颗粒形态特征,并探讨了颗粒形态与增塑糊黏度之间的关系。     

研磨对EPVC糊性能的影响

介绍了研磨前后EPVC糊黏度的变化情况,结果表明:研磨可增大EPVC糊黏度,随着研磨比例的增大糊黏度逐渐增大,但随着放置时间的延长,研磨前后糊黏度趋于一致。     

运用正交设计开发氯乙烯-醋酸乙烯酯共聚糊树脂

介绍了开发氯乙烯 -醋酸乙烯酯共聚糊树脂的必要性及生产原料、工艺过程 ,并进行了正交设计优化乳化体系的试验。结果表明 :A3 B3 C2 为最佳条件 ,即当单釜加料主乳化剂 5 5 g,助乳化剂A 2 5 g ,助乳化剂B 8g,制得的氯乙烯 -醋酸乙烯酯共聚糊树脂的B型粘度贮存稳定性最佳 ,主乳化剂投料是影响B型粘度贮存稳定性的重要因素     

聚氯乙烯糊树脂颗粒形态与增塑糊性能关系的研究

用激光散射法对聚氯乙烯糊树脂 (PPVC)浆料粒径及其分布和粉料颗粒粒径及其强度进行了测定和研究。结果表明 :初级粒子的粒径大小和分布是决定 PPVC树脂糊性能的关键因素 ;在一定范围内 (3 0～ 60μm) ,二次粒子颗粒强度即二次粒子的解碎程度是影响 PPVC树脂成糊性能的重要因素之一     

An improved method for increasing pseudoplasticity in vinyl plastisols

It has been established that the addition of very fine particles in a vinyl plastisol will increase viscosity. These particles may range from 100 to 5,000 angstroms. High viscosity would also be the result of lowering plasticizer levels but with the consequence of increasing product hardness and plastisol dilatancy. Another effect of fine particle addition is an increase in pseudoplastic behavior. This pseudoplasticity is vital for knife coating open weave fabrics or other processes in which the plastisol must be thick enough so as not to run or strike through. But at high shear (under the knife), it must spread easily. A common fine substance currently used for these purposes is fumed silica (70–140Å). There have also been some specialty dispersion resins for add-in pseudoplasticity. A new method utilizes the high efficiency and low cost of vinyl latex. Such small amounts are generally required that the water and surfactant content do not impair surface quality of the product. Preplasticized latex is particularly effective. As little as three parts (dry basis) per hundred dispersion resin increases Brookfield viscosity by 25 to 40 thousand centipoises. Pseudoplastic behavior is increased by over 100 percent. Its usefulness has been demonstrated at higher and lower plasticizer levels.     

抛光膏中磨料的解析

利用SEM，EDS分析了抛光膏中磨料的形状，尺寸和成分。结果表明，进口抛光膏中采有的磨料是直径为2－5μm的柱状氧化铝。