聚氯乙烯糊树脂颗粒形态与增塑糊性张关系的研究

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（30－60μm）,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。     

聚氯乙烯糊树脂粉料与增塑糊性能关系——调节糊粘度的可能性

本文阐述了聚氯乙烯糊树脂的颗粒结构特征,喷雾干燥和后处理的条件对糊树脂颗粒粒径分布与树脂粉料在增塑剂中解碎难易的影响以及不同增塑糊的流动性能;提出了控制糊粘度的可行性;建立了掺混增塑糊糊粘度计算的经验公式和胶乳粒子准单峰分布的增塑糊牛顿型高剪切极限粘度的数学模型。     

激光衍射散射式测粒技术在聚氯乙烯糊树脂粒径分析中的应用

介绍了激光衍射散射式测粒技术在聚氯乙烯糊树脂(PPVC)粒径分析中的应用情况,讨论了实验条件的优化。结果表明:激光衍射散射式测粒技术的可测粒径范围广、测量过程快速、测量结果准确,能准确地测量具有双峰分布的样品,是测量和表征PVC乳液颗粒粒径及粒度分布的理想方法。     

种子乳液法PVC树脂糊性能影响因素的分析

本文从单体质量、聚合配方、乳胶贮存时间、乳胶后处理、干燥方式五个方面阐述了对乳液法PVC树脂糊性能的影响。证实了PVC糊树脂糊粘度高低是初级粒径大小、分布和次级粒子颗粒形态综合作用的结果。     

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。     

微悬浮法聚氯乙烯糊树脂流变性能影响因素分析

采用旋转流变仪测试微悬浮法聚氯乙烯糊树脂的流变性能,重点分析了聚氯乙烯糊树脂的颗粒形态、粒度分布、分子质量及其分布对流变性能的影响。     

聚氯乙烯糊用掺混树脂生产技术

聚氯乙烯糊用掺混树脂是一种在使用时通过掺混来代替PVC增塑糊中部分糊树脂的PVC树脂。它能降低PVC增塑糊粘度并大幅度降低糊料成本。这种树脂可用悬浮法,本体聚合法进行均聚或共聚制得。B.F.Goodrich公司首先在六十年代利用改进的悬浮法开发了这种产品。此树脂要求粒子最好呈球形、外表光滑、粒度分布窄、平均粒径在10～80μm,且不存在200μm以上的颗粒、K值为57～70;还     

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。     

粒度仪在糊树脂生产中的应用（一等奖）

粒度仪在糊树脂生产中的应用（一等奖）西安化工厂杜延军，张宇，寇养朝在乳液聚氯乙烯（简称ＥＰＶＣ）工业生产过程中，影响ＥＰＶＣ树脂糊粘度的决定因素是其初级粒子的粒径大小和分布及次级粒子的结构形态。而糊粘度是糊树脂一个很重要的指标。因而正确、快速地测定Ｅ...     

乳液聚氯乙烯树脂的形态结构与其增塑糊流变性能的关系

本文报道了对乳液聚氯乙烯树脂进行流变性能测试、对其初级粒子进行电子显微镜观察和对次级粒子进行显微镜和扫描电子显微镜观察的结果,初步阐明了初级粒子粒径大小及分布和次级粒子的形态结构对增塑糊流变性能的影响。     

VCM／VAC共聚掺混树脂的合成及性能研究

本文介绍用特殊悬浮法合成共聚掺混树脂的方法,并讨论了粒经、掺混树脂含量等因素对糊性能的影响.结果表明,通过使用多元混合引发剂和悬浮剂及加入适量的助分散剂、界面活性剂、调粒剂等,并通过控制搅拌速率、温度等工艺条件能有效地控制粒子的粒径、粒度分布及粒子形状,从而制得具有良好性能和粒度均匀的掺混树脂;在一定的粒径范围内(25～40μm),掺混树脂的平均粒径越大,对降低糊粘度的效果越好;增加掺混树脂的含量对降低初始糊粘度更为有利,在PVC糊树脂中加入一定量的掺混树脂可降低塑化温度,缩短塑化时间,从而改善了PVC糊树脂的加工性能.     

十二烷基硫酸钠碳链分布对PVC糊树脂特性的影响

采用不同种类的市售十二烷基硫酸钠作为乳化剂生产PVC糊树脂,研究了十二烷基硫酸钠的碳链分布对PVC糊树脂粒度分布、糊黏度(B式)、72 h增稠率以及标准糊S流动性的影响,设计出适合PVC糊状树脂生产的配方。     

导电（抗静电）聚氯乙烯

阐述了影响炭黑填充聚氯乙烯（PVC）导电笥的诸多因素,分析后可知：炭黑在PVC树脂内的分散性是影响其导电性和加工性的关键因素之一;而表面积和结构度可影响炭黑的分散性。当炭黑粒径小于2nm时,其具有很强的吸附能力,需要更多的能量浸润,故分散较困难。同时,由于炭黑吸附在PVC分子链上,降低了PVC的流动性,即降低了加工性能,但提高了其玻璃化温度和力学强度。     

PVC糊树脂在下游行业中的应用

阐述了PVC糊树脂的生产方法、基本配方、工艺技术要点及其在主要应用领域的市场前景等,分析了影响PVC糊树脂加工性能的主要因素。     

水泥粒径分布对水泥石孔结构与强度的影响

通过计算不同粒径分布水泥样品的堆积密度和测定水泥石强度和孔结构,探讨水泥粒径分布对水泥石强度和结构的影响。研究表明：适当的水泥粒径分布可以使水泥具有最佳的堆积密度,并使水泥水化物的生成量与水泥浆初始孔隙量相匹配,从而得到孔隙率较小的密实而均匀的水泥石,使水泥石的性能提高。     

Analysis of the relationship between particle size distribution of α-calcium sulfate hemihydrate and compressive strength of set plaster—Using grey model

Particle size distribution (PSD) is one of the important factors associated with the strength property of cementitious materials. However, the relationship between PSD of α-calcium sulfate hemihydrate (α-HH) and compressive strength of set plaster is not well known. The plaster system could be regarded as a grey system and a grey model was developed to explore the relationship. The grey model shows that the compressive strength is derived from the combined action of each particle fraction, which could be divided into two groups. One works with positive effect: the particle fractions of 0-20 μm, 20-50 μm and 90-140 μm. The other works with negative effect: the particle fractions of 50-90 μm and > 140 μm. Variations of the compressive strength with the increment of specific particle fractions, which result from actions of particles on the hydration rate and the characteristics of pore structure, are in general agreement with the results given by the grey model. The availability of the grey model is restricted by the water-hemihydrate weight ratio (W/H) giving standard consistency of α-HH paste. The results indicate that the grey model could provide a potential method to evaluate the relationship.     

Study on PVC composites containing Eugenia jambolana wood flour

This article describes the properties of composites using unplasticized PVC matrix and wood flour (obtained by crushing the bark of Eugenia jambolana) as filler. Composites were prepared by mixing PVC with varying amounts of wood flour (ranging from 10–40 phr; having particle sizes of 100–150 μm and <50μm) using two‐roll mill followed by compression molding. The effect of wood flour content and its particle size on the properties, i.e., mechanical, dynamic mechanical, and thermal was evaluated. Tensile strength, impact strength, and % elongation at break decreased with increasing amounts of wood flour. Stiffness of the composites (as determined by storage modulus) increased with increasing amounts of the filler. Modulus increased significantly when wood flour having particle size <50 μm was used. Morphological characterization (SEM) showed a uniform distribution of wood flour in the composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

PA6/POE/POE-g-MAH分散相态与性能研究

研究了PA6/POE/POE-g-MAH分散相态与性能。结果表明:在不含POE-g-MAH的PA6/POE体系中,POE平均粒径为7.5μm,且大小分布很不均匀;掺入POE-g-MAH后,弹性体粒径迅速变小,加入10%的POE-g-MAH,其平均粒径为0.6μm。在POE/POE-g-MAH为30/70时,弹性体平均粒径为60nm;而只用POE-g-MAH时,其平均粒径只有50nm。分散相粒子越小,粒径分布越均匀。但粒径小于0.2μm时,对PA6增韧效果不佳。弹性体分散相粒径的大小与分布是影响共混物韧性的主要因素,但不影响共混物的屈服强度和模量。     

Nonrigid microporous PVC sheets: Preparation and properties

The non‐rigid microporous PVC films are prepared by mono‐axially stretching nonporous sheets containing fillers which show an average particle size of 2 to 10 μm. The nonporous PVC film is generated from paste‐like PVC. The influence of recipe components on the mechanical properties, morphological behavior and permeability to water vapor and water was investigated as well as the influence of the stretching ratio. Filled PVC pastes exhibit higher values for viscosity than those of pure polymer mixtures. For processing the compounded paste by means of a doctor blade a low viscosity is required meaning the amount of filler is limited by the resulting paste viscosity. Due to dewetting, the filler initiates the holes of the microporous system during the stretching process. Empirically, a minimum of about 15 vol % filler particles are necessary in order to achieve an interconnected air hole system. Varying the components PVC, plasticiser and filler, PVC membranes could be prepared with high water vapour permeability and high waterproofness simultaneously. To utilize the membranes commercially a continuous preparation process was developed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010