高浸透性大分子聚酯乳液的研制

1前言 随着池窑生产的发展,原有的浸润剂在快速浸润性和快速浸透性方面无法得到满足.意大利DSM公司聚酯乳液是公认的喷射纱浸润剂最好的成膜剂.本项目的目的是研制出能工业化生产的与DSM公司产品质量相当的聚酯乳液,替代进口,节约外汇,满足我国池窑发展需要,争创良好的经济社会效益.     

喷射无捻粗纱浸润剂专用MC—2043聚酯乳液的研制

本文叙述了ＭＣ－２０４３聚酯乳液的生产方法、性能和应用,用喷射粗纱浸润剂制得的粗纱完全满足喷射成型的使用要求,并与国内外同类产品作了比较,各项性能达到国外先进水平。     

玻纤浸润剂用聚醋酸乙烯酯乳液的研究

介绍了聚醋酸乙烯酯（ＰＶＡｃ）乳液的制备工艺、配方及乳液在玻璃纤维浸润剂中的应用,探讨了乳化剂选择和胶体保护剂改性对玻纤喷射纱产品性能的影响。     

高分子量乳液型减阻剂的合成及评价

采用反相乳液聚合方法制备了一种用于滑溜水压裂液的高分子量乳液型减阻剂。考察了复合乳化剂对乳液减阻剂稳定性的影响,研究了乳化剂含量、聚合温度和引发剂浓度对减阻剂分子量的影响,分析了减阻剂的分子结构、乳液粒径大小分布和减阻效率。实验结果表明:m(Span80)∶m(Tween80)∶m(OP-10)=20∶2∶1时乳液最为稳定;在18℃、乳化剂在油相中质量分数为15%、引发剂质量为单体质量的0.015%时,得到分子量达1.8×107g/mol的稳定乳液型减阻剂。在清水中加入0.05%的减阻剂,减阻率高达62.8%。     

Preparation of high molecular weight monodisperse polystyrene latexes by concentrated emulsion polymerization

The preparation of high molecular weight monodisperse polystyrene (PS) latexes by the concentrated emulsion polymerization is investigated. The PS latexes thus obtained have diameters in the range of 0.1–0.3 μm. The average size and the dispersity of the latexes are dependent on the concentration of surfactant (SDS), the monomer volume fraction, and the amount of monpolymerizable additive (decane). The ionic strength does not seem to affect the size but affect the dispersity of the latexes. Under proper conditions, monodisperse particles can be prepared with a quite small standard deviation. © 1993 John Wiley & Sons, Inc.     

基于分子量分布指标的聚酯生产过程模拟方法

提出一种以分子量分布为目标的聚酯工业生产过程流程模拟方法,针对通用流程模拟软件Aspen Plus在逐步聚合（step-growth）反应机理下不能计算分子量分布指数和分子量分布曲线的不足,通过外置接口程序从后台运行的Aspen源文件（*.bkp/*.apw）中读取数据,实现分子量分布曲线的可视化和其他质量指标的计算。以聚对苯二甲酸丁二醇酯（PBT）工业生产中的预缩聚过程为建模实例,在Aspen Polymers Plus软件平台上建立基于严格过程机理的聚酯工业预缩过程框架模型。根据分子量及端羧基浓度随动力学参数变化的灵敏度,利用工业操作参数及分析数据整定动力学参数,进一步通过外置接口程序计算PBT的分子量分布,重均分子量、分子量分布指数误差分别为4.2%、5.6%,为聚酯生产过程的分子量分布可视化提供基础。     

高分子量HDPE薄膜级树脂的开发

综述了国内外高分子量高密度聚乙烯薄膜级树脂的性能、生产工艺、代表牌号、市场、应用领域和发展趋势,重点介绍了几种代表性的生产工艺,并根据我国该薄膜级树脂生产和消费现状,提出了今后发展的建议。     

Preparation of high molecular weight poly(vinyl pivalate) with high yield and high molecular weight poly(vinyl alcohol) by emulsion polymerization of vinyl pivalate and saponification

To prepare high molecular weight (HMW) poly(vinyl pivalate) (PVPi) with high yield and high linearity which is a promising precursor for syndiotactic poly (vinyl alcohol) (PVA), vinyl pivalate (VPi) was emulsion polymerized, using 2,2′‐azobis(2‐amidinopropane) dihydrochloride (AAPH) as an initiator and sodium dodecyl sulfate (SDS) as an emulsifier. The effect of the polymerization conditions on the conversion, molecular weight, and degree of branching was investigated. PVA with maximum number‐average degree of polymerization (P_n) of 6200 could be prepared by complete saponification of PVPi, with P_n of 13,300–16,700 obtained at polymerization temperature of 50°C, using SDS and AAPH concentration of 2.0 × 10^?3 mol/L of water and 1.0 × 10^?3 mol/L of water, respectively, and the maximum conversion was about 90%. From the emulsion polymerization of VPi, spherical PVPi with high yield was effectively prepared, which might be useful for the precursor of syndiotactic PVA micro‐ and nano‐spheres with various surface properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 410–414, 2007     

乳液聚合法合成高相对分子质量聚醋酸乙烯酯的研究

本文采用过硫酸铵/亚硫酸氢钠氧化还原体系低温引发醋酸乙烯酯乳液聚合,分别讨论了聚合温度、单体用量、十二烷基硫酸钠(SDS)用量、过硫酸铵用量、亚硫酸氢钠用量等因素对聚醋酸乙烯酯粘均相对分子质量的影响。通过调节单体浓度、SDS浓度、过硫酸铵浓度、亚硫酸氢钠浓度和聚合温度,合成出高相对分子质量的聚醋酸乙烯酯,用GPC法对其进行表征,粘均相对分子质量为1.07×106,相对分子质量分布为2.75。     

乳液聚合法合成高相对分子质量聚醋酸乙烯酯的研究

采用过硫酸铵/亚硫酸氢钠氧化还原体系低温引发醋酸乙烯酯乳液聚合,合成出分子量为1.07×106、分子量分布为2.75的聚醋酸乙烯酯。讨论了聚合温度、单体用量、十二烷基硫酸钠(SDS)用量、过硫酸铵用量、亚硫酸氢钠用量等因素对聚醋酸乙烯酯黏均分子量的影响,并用GPC法对其进行表征。     

Molecular weight characterization of polybutadiene rubber with high molecular weight and broad molecular weight distribution

Following the molecular weight characterization of two polybutadiene samples, it was found that M _w from gel permeation chromatography with universal calibration and light scattering were in agreement, but M _n by gel permeation chromatography was less than M _n from membrane osmometry. A more detailed analysis revealed that the high molecular weight and broad molecular weight distribution of the two samples forced two corrections to the membrane osmometry results for (a) diffusional layer effects caused by high solution viscosities, and (b) solute permeability of the membrane. In the latter effect, the high viscosities of the solutions prevented actual diffusion through the membrane, but “reflection” of these species as defined by the Staverman coefficient prevented an accurate M _n determination. After making these corrections, it was found that M _n from membrane osmometry using a very tight membrane was in very good agreement with M _n from gel permeation chromatography. A method is demonstrated for obtaining M _n from a combination of membrane osmometry and gel permeation chromatography, where membrane osmometry data from membranes of different porosities (after corrections for diffusional layers and membrane reflection) are used to verify the accuracy of the gel permeation chromatography data as representing the true molecular weight distribution, allowing the gel permeation chromatography data to be used to calculate M _n.     

高温快速固化高相对分子质量韧性环氧树脂研究

采用己二酸和对苯二酚对液态低Mn(相对分子质量)的EP(环氧树脂)进行扩链改性,合成了含柔性链段的高Mn固体EP。采用差示扫描量热(DSC)法对韧性EP/酚类固化剂体系的反应活性和固化反应动力学进行了研究。结果表明:韧性EP的环氧值(0.165)和软化点(77℃)均高于市售EP,其反应活性较高(140℃时凝胶时间仅为79 s,200℃时凝胶时间已缩短至16 s),并且韧性EP因软化点较高而不会结块,故其完全满足防腐粉末涂料高温快速固化的使用要求。采用Kissinger法、Ozawa法和Crane法等计算出该固化体系的反应活化能为73.10 kJ/mol,反应级数为0.932。