用钙系催化剂合成月桂醇聚氧乙烯醚

研究了以不同的羧酸钙和月桂醇钙为催化剂的月桂醇聚氯乙烯醚(A_(12)POE)的合成,并研究了以上述钙化合物为主催化剂的复合催化剂中一些酸性助催化剂对反应的影响。结果表明几种羧酸钙的活性顺序为丙酸钙>乙酸钙>硬脂酸钙。月桂醇钙的活性与丙酸钙相似,而乙氧基化产物质量优于后者。对催化活性和反应产物质量综合比较,表明月桂醇钙明显优刊专统的氢氧化钠催化剂。在乙酸钙或月桂醇钙中加入酸助催化剂使催化活性提高,反应诱导期缩短。     

Influence of Droplet Charge on the Chemical Stability of Citral in Oil-in-Water Emulsions

Abstract: The chemical stability of citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H⁺) concentration around negatively charged droplet surfaces may account for the more rapid citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of citral in emulsion systems.     

脂肪醇聚醚型水性胺环氧固化剂的合成及性能

由高级脂肪醇聚氧乙烯醚(OE-6)、甲基四氢邻苯二甲酸酐(MTHPA)经酯化反应得到甲基四氢邻苯二甲酸单酯(MTHPME),而后其与液体环氧树脂(E-51)反应得单环氧甲基四氢邻苯二甲酸双酯(SEMTHPDE),最后经多元胺扩链及苄基缩水甘油醚封端,得到脂肪醇聚醚型水性胺类环氧固化剂(PEAWAECA)。对影响反应的因素:物料配比、反应时间、反应温度及催化剂用量等进行了考察并以红外光谱对产物结构进行了表征。结果表明,MTHPME的最佳合成工艺为:MTHPA与OE-6物质的量比1∶1,反应温度110℃,反应时间2.5 h;SEMTHPDE的最佳合成工艺为:E-51与甲基四氢苯酸单酯物质的量比为1.04∶1,反应温度115℃,反应时间3.5 h,对该产物与水性环氧AB-EP-20复配制备的双组分涂料漆膜性能分析表明,环氧基与胺氢物质的量比为1.1时,涂膜柔韧性达1 mm、铅笔硬度达3 H、附着力达1级、耐冲击性达50 kg/cm,改善了环氧树脂涂膜较脆的缺陷。     

Polymerization of fluoroacrylate and guar gum copolymer as a new pretreatment paste for ink‐jet printing of polyester

A novel pretreatment paste containing fluoroacrylate copolymer and modified Guar Gum was carried out on the polyester fabric to provide partial water repellency and printability after inkjet printed with water‐based disperse dye inks. The stable fluorinated pastes were prepared via miniemulsion polymerization of fluoroalkyl acrylates, styrene, 2‐ethylhexyl acrylate, and modified guar gum in the presence of AIBN as initiator, CTAB and polyoxyethylene polyaryl ether as surfactants under suitable reaction conditions. In the analysis of monomer conversion and particle size, the highest polymerization rate with smallest particle size was obtained with increasing concentration of surfactants and initiator but the decreasing degree of substitution of guar gum to imply stronger interactions between fluoroacrylate monomers, hydroxyl groups of modified guar gum and EO units of nonionic surfactants. The 30% of stock fluorinated paste with urea concentration of 6% provided the prints with highest K/S value, satisfactory edge acuity and least color difference between front and back sides of the fabric to show more transparency. The rating 80 of water repellency tested on the best treated polyester fabric demonstrated stain proof properties after sprayed with water and dried. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

镁铝复合介孔氧化物催化月桂酸甲酯乙氧基化反应

以十二烷基硫酸钠为模板剂、乙二胺为碱性介质,采用水热法合成了镁铝复合介孔氧化物(MMAO),采用氮吸附-脱附、X射线衍射、程序升温脱附和热重-差热分析等方法对MMAO进行了表征,并考察了MMAO在月桂酸甲酯乙氧基化反应中的催化性能。表征结果显示,合成的MMAO具有介孔结构特征,平均孔径为3.2nm,比表面积为280m2/g,孔体积为0.18cm3/g。实验结果表明,MMAO催化剂在月桂酸甲酯乙氧基化反应中具有较高的催化活性,适宜的合成条件为:反应温度180℃、初始压力0.6～0.7MPa、MMAO催化剂用量为月桂酸甲酯质量的3%。在此条件下得到的月桂酸甲酯聚氧乙烯醚的相对分子质量分布较窄,当环氧乙烷平均聚合度为5时,月桂酸甲酯聚氧乙烯醚的相对分子质量分布选择性系数为18.50。     

香兰素基非离子表面活性剂的动态表面张力与气/液界面吸附行为

通过最大气泡压力法测定香兰素基聚氧乙烯醚(VAEO)的动态表面张力,利用Word-Tordai方程研究其在气/液界面的吸附行为。结果表明,质量浓度低于临界胶束浓度(cmc)时,VAEO在吸附前期为扩散控制吸附,在吸附后期为混合动力控制吸附;质量浓度大于cmc时,为混合动力控制吸附,胶束不影响吸附行为。VAEO_(10)和VAEO_(20)的扩散系数D的数量级为10~(-11)m~2/s,比文献报道的壬基酚聚氧乙烯醚(NPEO_9)低一个数量级。     

脂肪醇聚氧乙烯醚磺酸盐表面活性剂合成进展

综述了当前耐温、耐盐脂肪醇聚氧乙烯醚磺酸盐表面活性剂的制备方法和研究进展。介绍了各种方法的优缺点，并进一步讨论了其工业化生产的可行性。     

用单月桂酸聚乙二醇山梨醇酐酯制备溶胶凝胶毛细管气相色谱柱及其分离能力之研究

采用溶胶-凝胶法制备了以单月桂酸聚乙二醇山梨醇酐酯为固定相的毛细管气相色谱柱.该毛细管气相色谱柱显示了良好的分离能力,色谱图表明：烷烃、芳烃、醇、胺、酸、酚、酯等各种极性与非极性化合物都可在该柱上得到很好的分离.良好的重现性与平稳的基线说明色谱柱出色的热稳定性.尖锐狭窄的峰形与2 802/m的理论塔板数表明较高的柱效.对称的色谱峰与数值为1的不对称因子则表明良好的柱惰性.     

Synthesis of an Alkyl Polyoxyethylene Ether Sulfonate Surfactant and Its Application in Surfactant Flooding

Surfactant flooding as a potential enhanced oil‐recovery technology in a high‐temperature and high‐salinity oil reservoir after water flooding has attracted extensive attention. In this study, the synthesis of an alkyl alcohol polyoxyethylene ether sulfonate surfactant (C₁₂EO₇S) with dodecyl alcohol polyoxyethylene ether and sodium 2‐chloroethanesulfonate monohydrate, and its adaptability in surfactant flooding were investigated. The fundamental parameters of C₁₂EO₇S were obtained via surface tension measurement. And the ability to reduce oil–water interfacial tension (IFT), wettability alteration, emulsification, and adsorption was determined. The results illustrated that IFT could be reduced to 10^?3 mN m^?1 at high temperature and high salinity without additional additives, and C₁₂EO₇S exhibited benign wettability alternate ability, and emulsifying ability. Furthermore, the oil‐displacement experiments showed that C₁₂EO₇S solution could remarkably enhance oil recovery by 16.19% without adding any additives.     

辛基酚聚氧乙烯醚琥珀酸酯磺酸二钠盐的合成研究

以辛基酚聚氧乙烯醚,顺丁二酸酐,亚硫酸钠为原料,合成了辛基酚聚乙烯醚琥珀酸酯磺酸二钠盐,探讨了反应温度和反应时间对酯化和磺化反应的影响