Dispersion—flocculation studies on a Goethite-clay system

Dispersion–flocculation studies on a Goethite–clay system using flocculants were carried out as a function of flocculant concentrations, pH of slurry, time of agitation and dispersant dosage. Also, the effects of pH and polymer concentrations on the adsorption behaviour of the system were investigated. Results show that well flocculated goethite was preferentially obtained from 4% goethite/kaolinite clay suspensions, with 50 ppm causticised starch in the slurry at pH values of 3–11·5 and with 50 ppm polyacrylamide at pH values of 3–8. Good flocs were also obtained on flocculation of the goethite suspension with 50 ppm polyacrylamide at pH values of 5–7, while the kaolinite suspension did not respond to the same dosage of causticised starch in the same pH range. Results further reveal that for the goethite/kaolinite suspension, the best results was obtained with 50 ppm polyacrylamide at pH values of 7–10. Based on the data generated in the study, it was concluded that causticised starch is a better flocculant than polyacrylamide for goethite suspensions although polyacrylamide is an excellent flocculant for kaolinite suspensions.     

甲氨蝶呤囊泡的制备和体外释放性能研究

用非离子表面活性剂和胆固醇为原料,采用薄膜分散法制备甲氨蝶呤囊泡,通过透析法分离未包封的药物,紫外分光光度法测定包封率和体外释药性。结果显示,Span 60与胆固醇形成的囊泡(VSpan 60∶VCHOL=5∶3),在50℃超声40 m in的条件下,对0.60 g/L的甲氨蝶呤包封率可达65%以上,在模拟胃流体和模拟肠流体中均有良好的缓释作用。     

Corrosion inhibition of carbon steel in acid chloride solution using ethoxylated fatty alkyl amine surfactants

Four novel non-ionic ethoxylated fatty alkyl amine surfactants (I–IV) were synthesised and investigated as corrosion inhibitors of carbon steel in 1 M hydrochloric acid solution using gravimetric, open circuit potential and potentiostatic polarisation techniques. The percentage inhibition efficiency (η%) for each inhibitor increased with increasing concentration until the critical micelle concentration (cmc) was reached. The maximum inhibition efficiency approached 95.1% in the presence of 400 ppm of the inhibitor (IV). It was found that the adsorption of the surfactants on carbon steel followed the Langmuir adsorption isotherm. Potentiostatic polarisation data indicated that these surfactants act as mixed type inhibitors. The values of activation energy (E _a*) of carbon steel dissolution in 1 M HCl were calculated in the absence and presence of 400 ppm of each inhibitor. Finally, scanning electron microscopy (SEM) was used to examine the surface morphology of polished carbon steel surfaces and those immersed in 1 M HCl in the absence and presence of 400 ppm of inhibitor (IV).     

酶法合成单脂肪酸甘油酯

该项目建立了一条脂肪酶催化棕榈油甘油解制备单甘酯的工艺路线。筛选出最佳酶源BUCT—11及相应的无机类载体作为脂肪酶固定化载体,并采用结晶法进行纯化。得到的单甘酯含量>90.0％,产品性能指标达到FCC标准。目前,单甘油酯主要采用化学法生产,能耗大、反应产物易降解、分离提纯困难。该工艺有望取代化学法过程。     

取代基及分子量对非离子型纤维素醚表面特性的影响

根据Washburn的浸渍理论(Penetration Theory)和van Oss-Good- Chaudhury的组合理论(Combining Theory)及应用柱状灯芯技术(Column Wicking Technique),对几种非离子型纤维素醚,如甲基纤维素、羟丙基纤维素和羟丙基甲基纤维素的表面特性进行了测试。由于这些纤维素醚的取代基、取代度和分子量不同,所以它们的表面能及其组成部分有着明显的差异。数据说明,非离子型纤维素醚Lewis碱大于Lewis酸,表面自由能的主要成分是Lifshitz-van der Waals力。羟丙基的表面能及其成分都大于羟甲基。而在相同取代基和取代度的前提下,羟丙基纤维素的表面自由能正比于分子量;而羟丙基甲基纤维素的表面自由能则正比于取代度,反比于分子量。实验还发现非离子型纤维素醚中的取代基羟丙基和羟丙基甲基的表面能似乎都大于纤维素的表面能,而实验证明所测试得出的纤维素的表面能及其成分的数据是与文献所吻合的。     

非离子表面活性剂烷基多苷的合成和应用

烷基多苷（APG）是葡萄糖（或淀粉）与天然脂肪醇在催化剂作用下缩合得到的一种非离子表面活性剂。APG具有优良的表面性能和环境相容性,已经成为新型的绿色表面活性剂,成为近年来的研究热点。对近年来APG的合成方法及其在诸多领域的应用进行了综述。     

新型非离子型水性环氧固化剂的合成及性能研究

为提高水性环氧涂料的固化性能和适用期,以自制聚酰胺和生物基戊二胺为起始原料,聚乙二醇二缩水甘油醚（ PEGGE）为亲水链段,双酚 A型环氧树脂（ E-51）为疏水链段,邻甲苯缩水甘油醚（ CGE）为封端剂制备了非离子型低温水性环氧固化剂,并与自制水性环氧乳液复配制得双组分水性环氧涂料。考察了环氧固化剂合成工艺参数及涂膜各项性能。结果表明：该固化剂含有较长的柔性脂肪烃碳链和聚醚链段能够提高涂膜的柔韧性;双酚 A型环氧树脂参与扩链反应能够解决与乳液不兼容等问题;苯环结构增加了涂膜的硬度;涂膜室温固化后性能优异,具有良好的物理机械性能、耐水性、耐酸碱性和耐盐雾性。     

硼酸双甘油葡萄糖苷月桂酸酯的合成及性能研究

以甘油葡萄糖苷、硼酸为原料,以对甲苯磺酸做催化剂,与月桂酸经酯化反应合成硼酸双甘油葡萄糖苷月桂酸酯表面活性剂,并采用红外光谱仪、核磁共振谱仪表征产物结构.实验结果表明:硼酸双甘油葡萄糖苷酯作为中间体与月桂酸进行反应,以用量为反应物总质量0.5%的对甲苯磺酸为催化剂,用30 mL的乙腈作为溶剂,在80℃下反应150 min,得到目标产物;其表面活性剂的表面张力为36.0 mN/m(20℃),临界胶束浓度为1.16×10-2 mol/L,并显示出良好的乳化性能.     

表面活性剂结构与乳液稳定性之间关系研究

以AEO、TX、EL、SPan—Tween系列非离子活性剂为乳化剂，白油和癸二酸二辛酯(DOS)为分散相，实验考察了各乳液体系的抗聚并稳定特性。根据乳液稳定性理论分析，认为非离子活性剂分子亲油基团的结构及其与油相分子的相似度对乳液油水界面粘性及相应乳液抗聚并稳定性会产生较大的影响。     

可水分散多异氰酸酯制备的研究进展

介绍了多异氰酸酯亲水改性的几种主要方法,以及国内外在此方面的研究进展,并进行了技术展望。