Synthesis of poly(methyl methacrylate)/silica nanocomposite through emulsion polymerization using dimethylaminoethyl methacrylate

Polymer/Silica nanocomposite latex particles were prepared by emulsion polymerization of methyl methacrylate (MMA) with dimethylaminoethyl methacrylate (DM). The reaction was performed using a nonionic surfactant and in the presence of silica nanoparticles as the seed. The polymer‐coated silica nanoparticles with polymer content and number average particle sizes ranged from 32 to 93 wt % and 114–310 nm, respectively, were obtained depending on reaction conditions. Influences of some synthetic conditions such as MMA, DM, surfactant concentration, and the nature of initiator on the coating of the silica nanoparticles were studied. Electrostatic attraction between anionic surface of silica beads and cationic amino groups of DM is the main driving force for the formation of the nanocomposites. It was demonstrated that the ratio of DM/MMA is important factor in stability of the system. The particle size, polymer content, efficiency of the coating reaction, and morphology of resulted nanocomposite particles showed a dependence on the amount of the surfactant. Zeta potential measurements confirmed that the DM was located at the surface of the nanocomposites particles. Thermogravimeteric analysis indicated a relationship between the composition of polymer shell and polymer content of the nanocomposites. The nanocomposites were also characterized by FTIR and differential scanning calorimetry techniques. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚丙烯酸酯防水乳液的研究进展

综述了聚丙烯酸酯防水乳液的理论研究进展，重点评述了组合功能单体、优选乳化体系和进行粒子设计三方面的改性手段。     

Synthesis and properties of PDMS modified waterborne polyurethane–acrylic hybrid emulsion by solvent-free method

A new type of polysiloxane modified polyurethane–acrylic hybrid emulsion was synthesized by solvent-free method and the polysiloxane was introduced into the soft segment of polyurethane chains using dihydroxybutyl-terminated polydimethylsiloxane (PDMS). The formed film from the hybrid emulsion could provide obviously higher water-resistance property. The preparation technologies such as the content of carboxy group and acrylic monomer, the rate and the time of emulsification were discussed systematically. The chain structure and the particle size were confirmed by the analysis of Fourier transform infrared spectroscopy and transmission electron microscopy, respectively. The effect of PDMS content on the water resistance and the mechanical property were investigated by absorbed water ratio, water contact angle and dynamic mechanical measurement.     

原油破乳脱钙复合剂的研制

介绍了原油破乳脱钙复合剂的筛选方法。所用的破乳剂有PY、UD 10、2 0 40、SDX、SL、硬脂酸 三乙醇胺 ,所用的脱钙剂有KL 1、KL 2、KL 3、KL 4、YH、EA、SJ、LP。首先将一定量的破乳剂与原油混合 ,振荡、静置 ,按油水分层情况及脱水率 ,筛选出较优的破乳剂。然后 ,在已加入破乳剂的原油中加入一定量的脱钙剂水溶液 ,振荡、静置 ,用燃烧瓶法处理油样 ,用原子吸收分光光度计测其钙含量 ,并与未经处理的原油对比。根据脱钙率 ,筛选出较优的脱钙剂。经过对破乳剂和脱钙剂的种类、用量、pH值等条件的选择 ,配出了针对俄罗斯原油、布伦特原油、扎非罗原油破乳、脱钙效果最好的复合剂PY YH、PY EA ,其脱钙率大于 80 %,脱水率大于98%,可直接用于炼厂的原油破乳脱钙工艺中。     

乳化炸药的乳化物理模型和理想乳化模态

文章以平推流模拟了乳化炸药乳胶质的形成过程,并建立了机械强制乳化的物理模型及理想模态。     

光面爆破专用炸药的研究

文章分析了光爆炸药的性能特点，提出了制造光爆炸药新方法。该炸药密度（０．３５、０．７０ｇ／ｃｍ￣３）与爆速（１３００、２２００ｍ／ｓ）可调，贮存性能稳定；爆轰感度好，能满足不同硬度岩石尤其是软岩的光爆需要。     

Influence of Two Salicylate Components on the Particle Size of an Oil-in-Water Emulsion with Nonionic Surfactants

This paper reports a study undertaken using techniques of static and dynamic light scattering to investigate the influence of sodium salicylate and methyl salicylate on droplet size of oil-in-water emulsions. The rates of changes were measured by determining the size and distribution of the oil droplet in the material. All emulsions showed a bimodal size distribution; the mean diameters and polydispersity were calculated from intensity. These data were analyzed with nonlinear regressions and bootstrap methodology. An amount of methyl salicylate component induced a decrease of mean diameter and standard deviation. On the contrary, sodium salicylate entailed the growth of all droplet populations and coalescence for the highest concentration.     

水溶性聚偶氮酯的研究

用Ｐｉｎｎｅｒ合成方法制备了用ＰＥＧ４００封端的水溶性聚偶氮酯，并表征了其结构；研究了热分解反应动力学及用于乳液聚合的动力学。结果表明，该种引发剂具有引发速度快、热分解机理简单和具有辅助乳化作用等优点。     

贮存稳定的聚氨酯干式复合胶粘剂的研究

研制了一种具有高固含量、低粘度的干式复合用双组分聚氨酯胶粘剂，考察了聚酯多元醇，扩链剂丙三醇／乙二醇（摩尔比）、NCO／OH（摩尔比），双组分胶配比以及缓凝剂等因素对该胶粘剂性能的影响，并用红外光谱对胶的固化过程进行了表征。结果表明，该胶粘剂具有较高的粘接强度，优良的低温流动性和贮存稳定性。     

低温导热绝缘胶粘剂研究

一种低温导热绝胶粘剂用于氢氧发动机系统表面温度传感器的端封和胶接安装，介绍了胶粘剂的技术要求，研究方案及试验结果。以DW－3超低温胶粘剂为基础，经改性设计后，仍能保持胶粘剂原有的耐低温特性，而且其导热，绝缘等性能均能满足设计和使用要求。