有机硅乳液的研究及进展

聚合物乳液及技术已成为高分子材料科学和工程的重要领域,在国民经济中发挥着巨大的作用。本文介绍了五种类型的有机硅乳液:聚硅氧烷乳液、硅微乳、聚硅氧烷/丙烯酸酯共混乳液、共聚乳液及复合乳液。阐述了各种乳液的制备方法,对各种乳液的性能及应用进行了综合评价,提出了有机硅乳液的发展前景。     

丙烯酸酯共混乳液的粒径和流变性能研究

将纯丙乳液和苯丙乳液通过乳液共混制备出丙烯酸酯共混乳液,探讨了共混比例、共混温度、共混pH值和共混工艺对丙烯酸酯共混乳液的粒径及其分布的影响,并进一步研究了共混乳液粒径大小及分布对其流变性能的影响。结果表明:共混乳液为假塑性流体;随着共混比例和共混温度的升高,共混乳液粒径减小,黏度增大;随着共混pH值的升高,乳液粒径先增大后减小,黏度总体上呈增大趋势;半连续工艺制备的共混乳液粒径分布最窄、黏度最大,连续工艺制备的共混乳液粒径分布最宽、黏度最小,间歇工艺制备的共混乳液粒径分布和黏度居中。     

有机硅氧烷 -丙烯酸酯乳液聚合研究进展

介绍了有机硅-丙烯酸酯乳液聚合物的3种制备方法及各种乳液的特点,对各种乳液的近期研究成果进行了总结。     

环氧乳液与含氟乳液的拼混研究

运用种子乳液聚合法制备了固含量(固体质量分数)为45%的含氟乳液;运用后乳化法制得了环氧乳液。ATR-FTIR测试表明环氧乳液与含氟乳液进行了有效的拼混。运用KrussK12型动态表面能分析仪测试了含氟涂膜对水和十六烷的接触角,对影响拼混乳液涂膜性能的因素如环氧树脂及其固化剂的比例、氟原子含量、成膜基材材质、成膜温度等进行了探讨研究。结果表明制备的含氟拼混乳液性能良好。     

Pickering乳液在菊酯类农药水乳液中的应用

通过十六烷基三甲基溴化铵(CTAB)对纳米二氧化硅(Si O2)进行原位疏水化,将其作为乳化剂,以正庚烷作为油相,成功制备了氯菊酯农药水乳液。通过表观照片、分水率、显微镜、流变仪等表征手段测试了Pickering乳液的稳定性和流动性。对制备过程中乳化剂用量、油水比等进行优化,确定了油水比(体积比)为7∶3、CTAB浓度为0. 1 m M、Si O2浓度为0. 7%为乳液最佳制备工艺。所制备的农药水乳液具有良好的应用性能。     

水性环氧乳液的制备及性能研究

采用新型乳化剂及相反转法乳化环氧树脂,制备性能好的水性环氧乳液,讨论了原料的选择、乳化剂的用量、乳化温度、乳液固含等对乳液性能的影响。结果表明:以环氧树脂E-44为原料,乳化剂用量10%、反应温度60℃制备的固含50%的水性环氧乳液,其稳定性及涂膜性能良好。采用激光粒度分布仪和透射电镜对乳液进行粒径外观和分布分析。     

高性能环氧树脂乳液的制备及性能研究

通过化学改性制备了一种性能优异的阳离子型环氧树脂乳液,对该乳液合成工艺进行了探讨,并研究了影响乳液及涂膜性能的因素。结果表明:采用环氧树脂E-51为原料制备的环氧树脂乳液稳定性好,分散相粒径为0.1～0.3μm,适用期为4 h,涂膜透明,硬度2H～3H,综合性能优良。     

微乳液技术制备纳米微粒的研究进展

综述了微乳液技术制备纳米微粒的研究现状，并对微乳液的配制及制备中影响纳米微粒的主要因素进行了讨论，提出了这一研究领域的发展方向。     

用于水性木器涂料聚合物乳液的制备

介绍了一种用于水性木器涂料的聚合物乳液的制备方法,分析了不同加料方式和不同滴加速度对乳液合成的影响,并最终合成出能够用于水性木器涂料的均匀、细腻的阳离子聚合物乳液。     

AMPS在聚醋酸乙烯酯乳液中的应用研究

传统上以聚乙烯醇(PVA)为乳化剂所制备的聚醋酸乙烯酯(PVAC)乳液存在黏度大、耐水性差等问题,在PVAC乳液的聚合过程中加入AMPS,研究了在无PVA条件下AMPS对乳液的聚合过程及性能的影响,并对相关性能进行了检测和对比分析。结果表明,AMPS可以明显提高PVAC乳液的贮存稳定性和电解质稳定性,与采用PVA为乳化剂制得的PVAC乳液相比,黏度由2600mPa·s下降到了97mPa·s以下、胶膜的吸水率由210%下降到了32.7%以下;使用无皂聚合方法制备PVAC乳液时,添加AMPS可以迅速减小乳胶粒的尺寸,提高乳液的稳定性和收率。     

聚氨酯缔合型增稠剂的研制及应用

利用聚乙二醇和二异氰酸酯聚合,并以酚类物质为链封端剂合成了缔合型增稠剂,检测和对比该产品与一支国外同类产品在乳液及乳胶涂料中的一些相关应用性能,结果显示,该产品与同类产品性能接近,具有一定的市场前景。     

Heterocoagulation as an Inclusion Coating Technique for Ceramic Composite Processing

Colloidal heterocoagulation in aqueous media was used to form coatings of alumina or polystyrene latex particles on alumina spheres and of alumina or latex particles on silicon carbide whiskers. The polyelectrolyte dispersants poly-(ammonium methacrylate) and poly(ethylenimine) were used to alter the inherent surface potentials of the materials to increase the applicability of this technique. In most cases, the coatings formed were partial monolayers, although thicker coatings of alumina were formed on the SiC due to aggregation of the alumina. The oxide coatings were relatively well adhered while the latex coatings were easily removed in aqueous media. The adherence of the latex coatings was improved by adding low alcohols to the heterocoagulating suspension.     

Performance of redispersible polymer powders in wall coatings

This study applied redispersible powder into wall coatings and compared the film microstructure and properties of dry-mixed coatings and corresponding latex coatings. It could be found that the dry-mixed coatings film had loose and uniform structure, while the latex coatings film was dense and had two-layered microstructure. Through the UV–vis spectra and dynamic light scattering, we found that the different microstructures of both coatings films were resulted from the different stability of reconstituted emulsion and original polymer emulsion, and one model was set up to demonstrate this process. The performance of dry-mixed coatings was worse compared with latex coatings, which was due to the weakened stability and adhesive ability of reconstituted emulsion after spray drying.     

Effect of particle size distribution on stress development and microstructure of particulate coatings

The role of pigment particle size distribution on stress and microstructure development was studied for coatings prepared from aqueous suspensions of ground calcium carbonate (GCC) and latex binder. Stress development was monitored using a modified beam deflection technique under controlled environment. Microstructure was characterized by scanning electron microscopy (SEM) and cryogenic SEM. For coatings containing only GCC particles and no latex, a wide particle size distribution resulted in a significant particle size gradient in the cross-sectional microstructure and irregular stress development. With latex addition, uniform microstructures were observed in coatings with either wide or narrow GCC particle size distribution. GCC/latex coatings prepared using GCC with a wide particle size distribution developed a higher stress than those prepared using GCC with a similar average particle size but a narrow particle size distribution. The higher stress is related to the particle packing that results in smaller pore sizes and larger capillary pressures that drive compaction. In coatings prepared with the same GCC particles but different latex binders, the stress and cracking behavior of the coating depends on the latex properties.     

环氧-丙烯酸酯类复合水性涂料的研究进展

综述了近年来国内外环氧-丙烯酸酯类复合乳液涂料的新进展,总结了环氧-丙烯酸复合乳液涂料的制备方法,以及复合乳胶粒的形态,展望了该领域今后的研究方向。     

颜料对乳胶漆耐洗刷性能的影响

乳胶漆的耐洗擦性能反映乳胶漆的综合性能。本试验系统研究了颜料体积浓度、填料用量、乳液聚合物、成膜助剂对乳胶漆耐洗擦性能的影响。试验发现增加颜料和填料用量，降低乳胶漆的耐洗擦性能，使用玻璃化温度低，弹性大，极性低的乳液聚合物，乳胶漆耐洗擦性能提高越明显；同时还发现使用成膜助剂可以显著改善乳胶漆的耐洗擦性能。     

乳液聚合法制备全氟碳涂料及性能的研究

以自制的全氟丙烯酸酯单体 ,经乳液聚合的全氟丙烯酸酯乳液共聚物配制的全氟碳乳液涂料 ,其耐水性、耐碱性等均优于传统的丙烯酸酯乳液涂料     

建筑反射隔热保温涂料的研制

介绍了以有机硅改性丙烯酸乳液为基料,不透明聚合物、空心微珠和红外辐射功能颜填料制备建筑反射隔热保温涂料的工艺技术,研究了几种功能颜填料及涂料体系的PVC值对涂料隔热保温性能的影响,乳液T_g值及阻燃剂对涂料耐沾污性和阻燃性能的影响。     

Sintering of latex particles in pigmented coatings. II. Influence of the latex particle size

The light-scattering coefficient S of coatings formulated from a mixture of an inorganic pigment and polystyrene latex particles may be enhanced significantly when the dry coating is heated in order to cause sintering of the polystyrene spheres. The relative increase in S depends on the size and the amount of the latex particles and the type of the inorganic pigment. Of the latexes examined (0.5, 0.2, 0.1, and 0.03 μm in diameter) the 0.2μm latex is the most effective in blends with platelike delaminated clay. The coatings based on spherelike precipitated calcium carbonate are less responsive to the heat treatment. The gloss of the clay–latex coatings is not significantly altered by the heat treatment up to 20 pph of latex; the gloss of the calcium carbonate coatings generally decreases upon heating.     

用于电脑调色的基础乳胶漆配方设计

分析了乳液体系、增稠体系对调色基础漆展色性的影响,并且探讨了调色基础乳胶漆中PVC与钛白含量的设计。