对甲苯磺酸催化合成乙二醇单硬脂酸酯

以硬脂酸和乙二醇为原料,采用对甲苯磺酸作催化剂合成乙二醇单硬脂酸酯。考察了影响反应的因素,实验结果表明酯化反应的最佳条件为:n(硬脂酸)∶n(乙二醇)∶n(对甲苯磺酸)=1∶3∶0·125,反应时间50min,带水剂甲苯用量为10mL。产率可达96·34%。     

Formation and investigation of microemulsions based on jojoba oil and nonionic surfactants

The properties of jojoba oil make it uniquely suited as a raw material for the cosmetics industry. Water-based, thermodynamically stable preparations of jojoba oil are essential in many formulations. New microemulsions were prepared based on jojoba oil and different nonionic surfactants, namely polyoxyethylene-(ethylene oxide)₁₀-oleyl alcohol (Brij 96V) and ethoxylated sorbitan esters (Tweens). The effects of the surfactants and of primary alcohols as cosurfactants on the isotropic regions of the phase diagram were elucidated. It was found that, up to a certain cosurfactant chain length, the isotropic region expanded considerably as chain length increased. The size of the isotropic region also increased as a function of the ethylene glycol content of the aqueous phase in microemulsions based on ethoxylated alcohol but shrank when ethylene glycol was included in microemulsions prepared with ethoxylated sorbitan esters. Secondary structural phase transitions from water-in-oil to bicontinous and to oil-in-water structures (as determined by measuring conductivity and viscosity) were found to be related to jojoba oil content. Dynamic light scattering and small angle X-ray scattering studies established that incorporation of jojoba oil into Brij 96V micelles caused micellar transformation from elongated to spherical droplets and a decrease in the aggregation number.     

Hollow calcium carbonate microspheres prepared in the presence of polyoxyethylene （20） sorbitan monolaurate and sodium dodecyl sulfate

Hollow calcium carbonate(CaCO3) microspheres were prepared in aqueous solution with the presence of polyoxyethylene(20) sorbitan monolaurate(Tween20) and sodium dodecyl sulfate(SDS).The microspheres were characterized with X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscope(TEM).The X-ray diffraction data showed that the hollow CaCO3 microsphere consisted of calcite crystals.The influence of Tween20 and SDS concentrations on the morphology of CaCO3 crystals was investigated.The results suggested that the"core-shell model"of Tween20/SDS micelle aggregated as templates,which could control the growth of hollow CaCO3 microspheres.The interaction between mixed surfactants and calcium ions played a critical role in organizing calcium carbonate in microscopic level.     

优质失水山梨醇单油酸酯的合成

以山梨醇和油酸为原料，采用新型催化剂一步法合成目标产物。探讨了催化剂配比、用量和反应温度对目标产物单酯含量、酸值(4～8mg KOH／g)、皂化值(140～160mg KOH/g)和羟值(190～210mg KOH／g)的影响。得到了适宜的反应条件。产品色泽浅无需经脱色处理可直接应用于医药、食品、化妆品等行业。     

表面活性剂T154和Span80对W/O型单重乳状液膜稳定性的影响

采用单因素实验法分别进行了表面活性剂T154和Span80制备W/O单重乳状液膜的研究。重点考察了表面活性剂体积分数、制乳搅拌速度、油内比、内相NaOH浓度和乳液静置时间对两种表面活性剂制备的乳状液膜破损率的影响并进行了比较。结果表明,T154和Span80制备的乳状液膜的破损率均随各考察因素的增大而降低或升高（除制乳搅拌速度外）,但前者降低或升高的幅度显著低于后者。实验确定了T154制备乳状液膜的最适宜条件,在此条件下,当乳状液膜静置时间为1、4、8 h时,其破损率分别为2.3%、4.7%和7.8%,显著低于Span80制备的乳状液膜的破损率9.2%、21.9%和48.4%。     

失水山梨醇单(叁)油酸酯的结构分析

ＴＬＣ和ＨＰＬＣ分析表明，Ｓｐａｎ－８０，８５的组成复杂。ＨＰＬＣ法可用来测定Ｓｐａｎ－８０，８５中单酯、双酯和多酯的相对含量，其结果可用来指导产品的合成。     

阳离子聚酯施胶剂的制备及应用

用二元酸和二元醇进行酯化缩聚,制得阳离子型聚酯乳液.所得乳液产品在中性条件下具有理想的施胶效果.同时研究了不同工艺条件对施胶效果的影响,并对聚酯施胶剂的作用机理进行了分析.     

广式月饼回软回油性能的改进研究

采用正交试验的方法,对用于改善广式月饼回软回油性能的复合乳化进行研究。结果表明,添加该乳化剂的月饼能迅速回软、回油,而通过添加丙酸钙作为防腐剂,能有效地抑制细菌和霉菌的生长,从而保证月饼具有良好的贮藏性能。     

非水相中脂肪酶转化失水山梨醇单油酸酯反应的研究

失水山梨醇单油酸酯可通过脂肪酶CAL在无溶剂体系中转化合成。对反应体系进行条件优化后,进行了10批酶法合成失水山梨醇单油酸酯。结果表明该酶具有较高的催化活性和稳定性,每批转化率均达92%以上,10批反应结束,酶活性仍有约70%,半衰期为921.4h。但单酯含量逐批略有下降,从最初85.3%降至约56.6%,与化学合成的产品比较,各项指标基本接近,但酶法合成的产品前5批单酯含量较高,均可达70%以上。     

Oil-in-Water Emulsions Stabilized by Sodium Caseinate or Whey Protein Isolate as influenced by Glycerol Monostearate

Competitive adsorption between glycerol monostearate (GMS) and whey protein isolate (WPI) or sodium caseinate was studied in oil-in-water emulsions (20 wt % soya oil, deionized water, pH 7). Addition of GMS resulted in partial displacement of WPI or sodium caseinate from the emulsion interface. SDS-PAGE showed that GMS altered the adsorbed layer composition in sodium caseinate stabilized emulsions containing < 1.0 wt % protein. Predominance of β-casein at the interface in the absence of surfactant was reduced in the presence of GMS. The distribution of α-lactalbumin and β-lactoglobulin between the aqueous bulk phase and the fat surface in emulsions stabilized with WPI was independent of the concentration of added protein or surfactant.