乳液聚合物耐水性的研究

采用自制的反应性乳化剂和普通乳化剂进行乳液聚合以改善乳液聚合物的耐水性。文中介绍了乳液制备方法,以及乳液聚合物膜的耐水性测定方法等,讨论了反应性乳化剂结构、用量对乳液聚合稳定性,聚合物机械稳定性及聚合物膜的耐水性影响。     

乳化剂对乳液型压敏胶的影响

简述了乳化剂对乳液型压敏胶聚合物，粘性能和耐水性的影响，并通过控制乳化剂用量、使用反应性乳化剂、加入适量增粘剂的或者使乳液聚合物部分交联来提高乳液型压敏胶的性能。     

苯丙乳液的最低成膜温度及其影响因素分析

简单介绍聚合物乳液的最低成膜温度及其测定方法,详细讨论了聚合物乳液组成、聚合物极性、单体亲水性、聚合物乳胶粒子性能、乳化剂、增塑剂及成膜助剂等因素对聚合物乳液最低成膜温度的影响。     

丙烯酸酯乳液粒径大小影响因素研究

乳液粒径及分布是表征聚合物乳液性能的重要指标之一。利用种子乳液聚合制备丙烯酸酯乳液的聚合过程中,探究阴离子乳化剂配比及用量、取种量、聚合物T_g对平均粒径的影响。结果表明,在反应过程中,增加釜底乳化剂的用量,可以有效减小乳液粒径;取种在一定的范围内可以改变乳液粒径;而聚合物T_g值对粒径的影响甚微。     

环氧基改性有机硅乳液聚合中乳化剂对聚合物乳液稳定性的影响

采用微乳液聚合法由D4开环聚合，含环氧基团的硅烷偶联剂共聚改性，合成了透明的环氧基改性有机硅微乳液。讨论了乳化剂对聚合反应速率、聚合物乳液粘度、乳胶粒径、聚合物乳液稳定性的影响。结果表明，采用阳／非离子型复合乳化剂10％(对乳液质量)有利于聚合反应进行，得到的环氧基改性有机硅乳液稳定。该环氧基改性有机硅乳液已经投产使用。     

苯丙微乳液的制备及工艺优化

运用种子聚合工艺，以SDS、OP-10为乳化剂，戊醇为助乳化剂合成了苯丙微乳液。研究了引发剂类型、复合乳化剂类型及含量、助乳化剂含量对苯丙微乳液聚合的影响。通过激光粒度测定仪及GPC对微乳液进行了测定，苯丙微乳液聚合物的平均粒径为41．8nm，并且具有很高的相对分子质量。     

乳液聚合中乳化剂对聚合物乳液稳定性的影响

简要叙述了聚合物乳液稳定性的测定方法，详细地讨论了乳化剂的类型、用量及加入方式等对丙烯酸酯类聚合物乳液的化学稳定性、机械稳定性及贮存稳定性的影响。     

纯丙弹性乳液的合成、应用及性能

研究了不同结构及不同配方的纯丙弹性乳液的合成及性能 ,并配制了聚合物乳液建筑防水涂料及聚合物水泥防水涂料。讨论了不同结构、不同Tg和不同引发剂、乳化剂用量对乳液性能及乳液 /水泥混合稳定性产生的影响。     

外墙外保温系统专用粘结剂的研制

介绍了外墙外保温系统专用粘结剂中乳液的合成、性能及其应用，讨论了聚合物乳液中丙烯酸含量、乳化剂种类及添加量等对其性能的影响，确定了该外墙外保温系统专用粘结剂中聚合物乳液与水泥的最佳配比。     

核/壳型苯乙烯-丙烯酸酯乳液的研制

采用预乳化工艺，半连续种子聚合法，通过MMA—St—BA—AA四元共聚反应，制得了具有核壳结构的苯丙乳液。讨论了乳化剂用量、阴／非离子乳化剂配比、核壳两阶段乳化剂配比以及功能性单体对乳液聚合反应和乳液性能的影响。表征了所得聚合物乳液的结构。     

二元复合驱采出液稳定性及破乳研究

用红岗原油、聚合物和表面活性剂配制二元复合驱模拟采出液,考察了化学剂对乳液稳定性的影响,并研究了破乳剂FPW-1的破乳性能.结果表明,聚合物、表面活性剂对乳液的稳定性均有影响,二者存在明显的协同效应,致使原油采出液更加稳定,破乳难度加剧;FPW-1破乳剂对于红岗油田二元复合驱模拟采出液具有较好的破乳性能.     

聚/表二元体系注入时机对驱油效果影响研究

随着化学驱技术的进一步发展,聚驱后仍有大量的剩余油存在地下,需要进一步对剩余油进行挖潜。聚/表二元驱作为聚驱后进一步提高采收率的方法,能有效的提高驱油效果。对于聚驱后储层非均质性更加严重的储层,聚/表二元驱能够进一步扩大波及体积,提高洗油效率,进而达到提高采收率的目的。以室内物理模拟为技术手段,分析了不同聚/表二元注入段塞尺寸对岩心驱油效果的影响。     

核／壳型可遮盖聚合物乳液的研制

采用了种子乳液聚合法,以可被碱溶胀的丙烯酸类聚合物为核,交联型的丙烯酸类高聚物为壳,合成了新型的可以代替部分钛白粉等颜料的可遮盖聚合物。讨论了乳化剂、单体、核壳比等对聚合物性能的影响,其中核壳比在1:15-1:25时,聚合物具有较好的遮盖效果。     

皮革涂料用丙烯酸酯核-壳乳液的研制

采用种子乳液聚合法，以交联型软性聚合物为核，交联型硬性高聚物为壳，合成了具有优异耐寒性及高温抗回粘性聚合物。讨论了乳化剂种类及应用、核／壳比等对聚合物性能的影响。     

PA6/PP/SEBS-g-MAH共混物的相容性研究

采用马来酸酐接枝(氢化苯乙烯/丁二烯/苯乙烯)共聚物(SEBS-g-MAH)作为增容剂,研究了增容剂用量对尼龙6/聚丙烯(PA6/PP)共混体系相态结构、力学性能的影响,以及在相同增容剂用量下不同PA6、PP配比对体系相形态的影响。结果表明,SEBS-g-MAH中的酸酐基团能与PA6末端的氨基发生化学反应,在PA6和PP的内表面形成PA6-SEBS接枝共聚物,明显改善了两相的界面相容性,并使共混物的力学性能得到显著提高。共混物冲击断面形貌的分析表明,共混物发生了明显的脆韧转变。     

Suspension polymerization of thermally expandable core/shell particles

Acrylonitrile (AN)-methacrylonitrile (MAN) copolymer particles with a core/shell structure were prepared by suspension polymerization. The particles were about 10-20 μm in diameter and had a hollow core containing an inert hydrocarbon. The influence of the monomer feed ratio and the polymerization temperature on the particle morphology was studied. One purpose of this study was to determine the boundaries for achieving a core/shell structure with the polymer encapsulating the hydrocarbon. When polymerizing at 62 °C, it was found that an initial AN/MAN feed ratio (f_AN) between 0.15 and 0.9 results in core/shell particles with encapsulated hydrocarbon. f_AN lower than 0.15 yielded solid particles with no hydrocarbon encapsulated while f_AN higher than 0.9 yielded particles built up entirely from agglomerates of smaller primary particles. In contrast, when polymerizing at 80 °C, a much narrower span of f_AN (0.5-0.85) yielded particles with hydrocarbon encapsulated. The influence on monomer conversion and the molecular weight of the polymer was also studied.     

Effects of Particle Size and Molecular Weight of Polyethylenimine on Properties of Nanoparticulate Silicon Dispersions

The effect of particle size on the zeta potential and rheology of nanoparticulate SiO₂ dispersions stabilized with the polymer polyethylenimine (PEI) was investigated experimentally. The particle size and molecular weight of the polymer had only a small influence on the amount of PEI needed and the achieved zeta potential of the suspensions. The polymer concentration range within which a stable dispersion could be produced was very narrow for the smallest particle size. Higher-molecular-weight PEI was more suitable to stabilize small particle dispersions. Under optimum conditions, Newtonian flow behavior was achieved for dispersions of 20 nm particles with a solids content as high as 25 vol%.     

In situ electrochemical Scanning Kelvin Probe Blister-Test studies of the de-adhesion kinetics at polymer/zinc oxide/zinc interfaces

Fundamental investigations of the polymer/zinc oxide/zinc interface corrosion stability were performed in situ by means of the electrochemical Height Regulated Scanning Kelvin Probe Blister-Test (HR-SKP-BT) under controlled atmospheric conditions. A hole under an adhesive layer film served as electrolyte reservoir to initiate cathodic de-adhesion processes. Then a combinatorial approach was undertaken to simultaneously study the influence of electrolyte pressure at constant defect polarisation and of relative atmospheric humidity on the de-adhesion rate. The time resolved blister growth and the propagation of the three phase boundary polymer/oxide covered zinc/interfacial electrolyte layer could be detected. It could be proven that the oxygen reduction induced electrochemical damage of the interface precedes the subsequent mechanical de-adhesion process. By variation of the relative atmospheric humidity the water concentration within the bulk adhesive and its interphase adjacent to the metal substrate could be adjusted. These processes were further analysed by peel-tests and in situ Attenuated-Total-Reflection Infrared Spectroscopy (ATR-IR) studies of water diffusion. A decrease of the interphasial water concentration led to a deceleration of the de-adhesion kinetics for constant defect conditions and to smaller interfacial ion transport rates. This could be assigned to an inhibition of the electron transfer reactions at the front of de-adhesion and an increased adhesion force between polymer film and oxide covered metal preventing the formation of an extended interfacial electrolyte layer.     

Formation and characteristics of cationic-polymer/bentonite complexes as adsorbents for dyes

The adsorption of cationic polymer, i.e., epicholorohydrin-dimethylamine polyamine (EPI-DMA), on bentonite particles was investigated under various conditions of bulk polymer concentration, pH, inorganic salts, and temperature. The resulting high adsorption rate and alkaline solution (pH = 7–11) effect indicated a strong electrostatic interaction between the clay particles and EPI-DMA molecules. Addition of salt can also influence the adsorption of EPI-DMA onto bentonite by affecting the clay particle sizes, the polymer zeta potential and etc. The Freundlich and Langmuir isotherm models were employed and fit the experimental data well in the low EPI-DMA concentration range 0.5–5.0 mg L^− 1. The enthalpy implied by the temperature dependence of adsorption of EPI-DMA on bentonite is 7.93 kJ mol^− 1, suggesting that neither coordination exchange nor chemical bond forces exit in this system. In addition, at high temperatures, larger amounts of EPI-DMA were adsorbed by bentonite, which indicated that increased entropy in the dissolved EPI-DMA molecules contributes to adsorption. The X-ray diffraction (XRD) analysis showed that besides the EPI-DMA molecules intercalated between the layers of bentonite, excess polymer molecules were adsorbed onto polymer loops protruding from the surface of the complex. The TGA and corresponding DSC plots demonstrated that the EPI-DMA polymer had intercalated into the clay layers and thus the EPI-DMA/bentonite was more hydrophobic than natural bentonite. With the addition of EPI-DMA polymer, the negatively charged clay particles increased to a net positive charge and the capacity for dye removal also went up with increasing polymer contents in EPI-DMA/bentonite complexes.     

PP/WSPET/ZnO三元共混合金的流变性研究

用CFT-500型毛细管流变仪研究了PP/WSPET/ZnO共混体系的流变性能。研究结果表明:PP/WSPET/ZnO共混合金为典型的假塑性流体,WSPET含量增加,流体产生不稳定流动的临界剪切速率增大。共混合金的表观黏度和零切黏度随WSPET含量和温度提高而减小。黏度对温度的依赖性随WSPET含量增加和剪切速率的增大而减小。