O/W型Pickering乳液的制备及其吸收紫外线性能研究

自制芦荟水溶液为水相,以橄榄油为油相,以氧化锌、二氧化钛、云母、碳酸钙颗粒及其混合粒子作为稳定剂,制备出了一种新型O/W型Pickering乳液。通过数码生物显微镜观察Pickering乳液的液滴粒径及稳定性,紫外分光光度计检测Pickering乳液的吸光度。结果表明,用氧化锌、二氧化钛、碳酸钙和云母混合颗粒所制备Pickering乳液均是O/W型,随着油水比的增大,Pickering乳液的液滴粒径增大;随着微小固体颗粒用量的增大,Pickering乳液的液滴粒径也会增大。以碳酸钙、氧化锌、二氧化钛、云母及其混合粒子为稳定剂制备的水包橄榄油Pickering乳液,对UVA段和UVB段紫外线均有较好的吸收。     

O/W型Pickering乳液的制备及其吸收紫外线性能研究

自制芦荟水溶液为水相,以橄榄油为油相,以氧化锌、二氧化钛、云母、碳酸钙颗粒及其混合粒子作为稳定剂,制备出了一种新型O/W型Pickering乳液。通过数码生物显微镜观察Pickering乳液的液滴粒径及稳定性,紫外分光光度计检测Pickering乳液的吸光度。结果表明,用氧化锌、二氧化钛、碳酸钙和云母混合颗粒所制备Pickering乳液均是O/W型,随着油水比的增大,Pickering乳液的液滴粒径增大;随着微小固体颗粒用量的增大,Pickering乳液的液滴粒径也会增大。以碳酸钙、氧化锌、二氧化钛、云母及其混合粒子为稳定剂制备的水包橄榄油Pickering乳液,对UVA段和UVB段紫外线均有较好的吸收。     

微乳—沉淀法制备纳米尖晶石型MgFe2O4及表征

首先对油包水（W／O)型微乳液进行了制备研究,探明了一定条件下W／O型微乳液中的最大增溶水量。进而利用W／O型微乳液作为“微反应器”并用沉淀法制备Mg(OH)2-Fe(OH)3复合氢氧化物,最后将此复合氢氧化物进行高温固相反应、晶化制得了纳米尖晶石型MgFe2O4。通过XRD、TEM及颜色测量,对纳米MgFe2O4进行了表征,探讨了纳米粒子的量子尺寸效应。     

水性抗菌罩光油的制备及抗菌性能

以水性丙烯酸酯乳液为主要连结料,添加纳米二氧化钛抗菌剂复配成水性罩光油。参考日本JIS Z2801:2000标准,研究了纳米二氧化钛种类和用量对水性罩光油抗菌效果的影响。结果表明,TIO-WPR010(锐钛型纳米二氧化钛水性溶液)的抗菌效果优于TIO-NP100(氮掺杂纳米二氧化钛粉体)。当TIO-WPR010质量分数为0.7%~0.9%时,所制备的水性抗菌罩光油经过48 h的抗菌试验,对金黄色葡萄球菌和大肠杆菌的抗菌率分别为91.84%和94.51%,能够满足白卡纸的抗菌要求。     

二氧化钛光触媒在金属镀膜与金属防护技术中的应用第一部分光触媒分散技术

介绍了二氧化钛的晶体类型和基本性质、典型的锐钛型二氧化钛的XRD图谱。对纳米粒子的团聚现象进行了解释。对纳米粒子的分散原理——高分子分散剂／界面活性剂分散和电解质分散进行了说明。分别介绍了水溶液中二氧化钛以及改性后的锐钛型纳米二氧化钛的Zeta电位与pH的关系。研究了锐钛型纳米二氧化钛在聚丙烯酸盐分散介质中的粒径分布。结果表明,在此分散介质中,纳米颗粒的分布比较集中,粒径小于50．7 nm的粒子占60％,其平均粒径远低于传统的涂料级和颜料级分散的粒子;该溶液呈现明显的丁达尔现象,光触媒活性高,在实验室存放24个月后质量稳定;将此溶胶涂至玻璃表面,所得涂膜透明度高。     

制备纳米BaSO4的W/O微乳液体系组成及稳定性

以TritonX 10 0 正己醇 环己烷 水制成W O微乳反胶团体系 ,通过测定体系的电导率和观察液晶相的出现确定相点绘制了各体系的拟三元相图 ,研究了温度、盐浓度和油相组分对W O微乳液体系稳定性的影响 .实验发现助表面活性剂与表面活性剂的配比对微乳液的稳定性有显著影响 .随着温度的升高 ,W O微乳液稳定区域减小 ,可通过升高温度对微乳液进行破乳 ;与以纯环己烷为油相的体系相比 ,油相中含有少量正己烷的体系具有更优异的性质 .所得结果为利用该W O微乳液体系制备纳米颗粒提供了基础数据     

Alg@TiO2微球稳定的Pickering乳液用做防晒乳成分的研究

为了开发一种兼具防晒功能和乳液稳定性的防晒乳配方,设计了一种负载二氧化钛纳米颗粒的海藻酸钙微球（Alg@Ti O₂微球）来稳定Pickering乳液,用作防晒乳成分。考察了油水比和微球含量对Pickering乳液的影响,探究了乳液类型,并进行了长期保存稳定性测试。结果表明,Alg@Ti O₂微球形状为球形,大小为2～6μm;Alg@Ti O₂微球中二氧化钛纳米颗粒含量为43%;微球与油水的三相接触角为120°;当油水比为1∶1,微球含量为3%（w/%）时,稳定的白油/水体系Pickering乳液为油包水型（W/O型）,经100 d室温保存后乳液状态保持稳定。通过紫外吸收实验,和包括市售防晒乳在内的其他3种防晒乳相比,该Pickering乳液具有优异的防晒性能。通过皮肤表面清洗实验,该Pickering乳液具有易清洗的特性。     

微乳-沉淀法制备纳米尖晶石型MgFe_2O_4及表征

首先对油包水 (W/O)型微乳液进行了制备研究 ,探明了一定条件下W/O型微乳液中的最大增溶水量。进而利用W /O型微乳液作为“微反应器”并用沉淀法制备Mg(OH) 2 Fe(OH) 3 复合氢氧化物 ,最后将此复合氢氧化物进行高温固相反应、晶化制得了纳米尖晶石型MgFe2 O4 。通过XRD、TEM及颜色测量 ,对纳米MgFe2 O4 进行了表征 ,探讨了纳米粒子的量子尺寸效应     

O／W／O多功能防晒乳液的开发

本文开发了一种高性能的防晒乳液,即使在炎热、潮湿环境中,使用感觉良好,在O／W／O多功能乳液中,把疏水的无机防晒成分同时分散在外油相和内油相中,获得了更高的防晒性能。     

纳米二氧化钛改性聚氨酯乳液性能初探

主要讨论了纳米二氧化钛对聚氨酯乳液的改性。首先讨论了在二氧化钛纳米分散液中制备聚氨酯乳液的可行性,分别制备了纳米二氧化钛改性的芳香族聚氨酯和脂肪族聚氨酯乳液,得到了稳定乳液。通过紫外光谱分析,发现脂肪族聚氨酯与纳米二氧化钛共聚乳液薄膜在紫外区域400-200nm区域出现很明显的吸收峰。纳米二氧化钛的加入使芳香族聚氨酯乳液胶膜的拉伸强度增强,断裂伸长率下降。此外,对试样进行了DSC分析,发现共聚物在136-145℃出现明显的新的吸热峰。     

A novel method for preparing oil-in-water-in-oil type multiple emulsions using organophilic montmorillonite clay mineral

A stable formula using oil-in-water-in-oil (O/W/O) type multiple emulsions was investigated. The components consisted of hydrophilic nonionic surfactant (HCO-60), organophilic montmorillonite, and lipophilic nonionic surfactant (DIS-14). O/W/O emulsions were prepared by a double-step procedure in which an O/W emulsion was prepared in the first step, and then the O/W emulsion was “re-emulsified” in an oil phase with organophilic montmorillonite. The diameter of the innermost oil droplets decreased with increasing HCO-60 content (0.1–3%), while the viscosity showed a maximum at 1% of HCO-60, indicating that the yiel of re-emulsification is highest at this condition. Viscosity of the O/W/O emulsion increased with increasing organophilic montmorillonite and DIS-14. According to the results of a phase ratio study, viscosity and stability of the O/W/O emulsion decreased at high weight fraction of inner oil phase (0.4–0.5), indicating that the excess amount of inner oil phase is absorbed by the outer oil phase. These results revealed that the weight fraction of inner oil phase should be kept below 0.3 for a stable O/W/O emulsion. A similar study on the weight fraction of O/W phase [фO/W)/O] suggested that the O/W/O emulsion is stable at ϕ(O/W)/O=0.65–0.70.     

Efficient Encapsulation of a Water-Soluble Molecule into Lipid Vesicles Using W/O/W Multiple Emulsions via Solvent Evaporation

We developed a novel method for preparing lipid vesicles with high entrapment efficiency and controlled size using water‐in‐oil‐in‐water (W/O/W) multiple emulsions as vesicle templates. Preparation consists of three steps. First, a water‐in‐oil (W/O) emulsion containing to‐be‐entrapped hydrophilic molecules in the water phase and vesicle‐forming lipids in the oil phase was formulated by sonication. Second, this W/O emulsion was introduced into a microchannel emulsification device to prepare a W/O/W multiple emulsion. In this step, sodium caseinate was used as the external emulsifier. Finally, organic solvent in the oil phase was removed by simple evaporation under ambient conditions to afford lipid vesicles. The diameter of the prepared vesicles reflected the water droplet size of the primary W/O emulsions, indicating that vesicle size could be controlled by the primary W/O emulsification process. Furthermore, high entrapment yields for hydrophilic molecules (exceeding 80 % for calcein) were obtained. The resulting vesicles had a multilamellar vesicular structure, as confirmed by transmission electron microscopy.     

石蜡油w／o／w型多重乳液的制备及其对维生素C的包裹

以多重乳液相对体积为衡量标准,探讨了石蜡油、乳化剂、以及第一相质量分数对石蜡油w／o／w型多重乳液稳定性的影响。结果表明制备石蜡油w／o／w型多重乳液的较佳条件为：第一相中石蜡油和乳化剂Span80质量分数分别为40％和8％,第一相质量分数为65％,乳化剂Tween80质量分数为1％。采用透析-紫外分光光度法研究了该多重乳液对维生素c的包裹能力,结果表明：多重乳液可以有效包裹维生素C,包裹率达98．55％,且能缓慢释放被包裹的维生素C。     

乳液聚合导致一种新的转相过程

借助电导率仪、光学显微镜和亚微粒子分析仪等测试手段。研究了乳液聚合导致一种新的转相过程,并用于八甲基环四硅氧烷的聚合中。研究表明:体系以 W/O 相态开始,单体由连续相向水相(分散相)内的胶束中扩散并发生聚合反应,形成 O/W/O 复合乳液。反应过程中连续相体积不断减小,分散相(O/W 复相)体积不断增大,当达到某一临界相比时,体系发生转相,转相后乳液为 O/W。对本实验物系,转相点临界相比主要由初始水油比和乳化剂浓度决定。同常规的乳液聚合相比,伴有转相现象的乳液聚合有其自身的特点,转相使得聚合速率、聚合物粒径及分布、乳液稳定性等发生变化。     

超声波对稠油乳化的影响

超声波会使稠油的组分发生变化,对稠油有一定的降粘作用。超声波作用高含水W/O乳状液在没有乳化剂存在的条件下,能够形成O/W乳状液,这种方式形成的乳状液与加乳化剂转相形成的O/W乳状液相比,稳定性比较差,液滴粒径分布范围变宽,但主要分布范围变窄,液滴分散情况较好。流变性虽然遵循幂律流体规律,非牛顿性有所减弱。从微观观察来分析,在本实验研究范围内,经超声波处理后的高含水W/O乳状液形成的O/W乳状液并非严格意义上的乳状液。     

Stability of vitamin A in oil-in-water-in-oil-type multiple emulsions

The stabilityof vitamin A was studied in thee different emulsions: oil-in-water (O/W), water-in-oil (W/O), and oil-in-water-in-oil (O/W/O). The stability of retinol (vitamin A alcohol) in the O/W/O emulsion was the highest among the thee types of emulsions; remaining percentages at 50°C after 4 wk in the O/W/O, W/O, and O/W emulsions were 56.9, 45.7, and 32.3, respectively. With increasing peroxide value of O/W and W/O emulsifiers, the remaining percentage of vitamin A palmitate and retinol in the emulsions decreased significantly, indicating that peroxides in the formulae accelerate the decomposition of vitamin A. Organophilic clay mineral (an oil gelling agent and a W/O emulsifier) also affected the stability of retinol; synthesized saponite was better than naturally occurring bentonite for retinol stability. The stability of retinol in the O/W/O emulsion increased with increasing inner oil phase ratio (φ_i), whereas in O/W it was unaffected by φ_i. Encapsulation percent of retinol in the O/W/O emulsion, the ratio of retinol in the inner oil phase to the total amount in the emulsion, increased with increasing φ_i. The remaining percent of retinol in the O/W/O emulsion was in excellent agreement with encapsulation percent, suggesting that retinol in the inner oil phase is more stable than that in the outer oil phase. Addition of antioxidants (tert-butylhydroxytoluene, sodium ascorbate, and EDTA) to the O/W/O emulsion improved the stability of retinol up to 77.1% at 50°C after 4 wk. We conclude that the O/W/O emulsion is a useful formula to stabilize vitamin A.     

三元复合驱中原油乳化作用研究

通过乳状液稳定实验考察了大庆油田碱-表面活性剂-聚合物三元复合驱过程乳状液的形成机理、乳状液类型及稳定性。结果表明,大庆原油与碱反应1d时,测得其浓相体积分数为25%,所形成的乳状液为O/W型乳状液,而随着原油与碱作用时间的增加,其浓相体积分数达到40%以上,形成W/O型乳状液,且乳状液稳定性随作用时间增加而增强。大庆原油与水溶性表面活性剂ORS-41溶液作用时,所形成的乳状液为O/W型,且乳状液的稳定性与原油和ORS-41作用时间的长短关系较小。原油与NaOH和ORS-41混合溶液作用时,形成上层为W/O型乳状液,下层为O/W型乳状液的混合体系。     

Regular-sized cell creation in microchannel emulsification by visual microprocessing method

A novel emulsification method was developed for making monodispersed regular-sized cells. Both oil in water (O/W) and water in oil (W/O) emulsion cells were generated by permeating an internal phase into a continuous phase through a silicon microchannel, which was designed and prepared by using semiconductor technology. The microprocessing of O/W (or W/O) emulsion cells was monitored and controlled with a microscope video system. Regular-sized O/W cells were made by a normal hydrophilic microchannel and a glass plate with use of an appropriate surfactant. On the other hand, W/O emulsion cells were made by a hydrophobic microchannel and a glass plate modified with a silane coupler reagent. Regular-sized W/O cells were also obtained; therefore, a suitable combination of organic phase, surfactant, and electrolyte should be carefully selected. There is a possibility for creating artificial biological cells with this method. In the water/triolein and lecithin system, when the amount of oil was decreased on the permeate side, polygon or fiber cell types were created, and each cell contacted its neighbors across a thin oil layer like a biological tissue.     

白油W/O/W型多重乳状液的稳定性研究

以多重乳状液相对体积为衡量标准,用显微镜直接观察,探讨了乳化剂的HLB值、质量分数、亲油亲水乳化剂体积比及油水的相比等对白油W/O/W型多重乳状液体系稳定性的影响。结果表明单一乳化剂体系中适宜的制备条件:乳液中乳化剂质量分数为12.2%,V(Span80)/V(Tween80)=7.5;适合多重乳液稳定的油水相比为:第一相体积比为2.5,第二相体积比为0.2。复合乳化剂体系中适宜的制备条件:第一相乳化剂的HLB值为6.5,V(复合乳化剂)/V(Tween80)=27.5,乳液中乳化剂质量分数为9.5%。     

Mass transfer studies on multiple emulsion as a controlled mass release system

A novel type of multiple emulsions which contain a microemulsion in macrodroplets, was prepared by a two-step emulsification procedure. Mineral oil was used as the oil phase with a mixture of Aerosol OT and Span 20 as primary emulsifiers. A water-in-oil microemulsion was prepared by gradual addition of water in oil containing both these emulsifiers. This microemulsion system, when dispersed in an aqueous solution containing secondary emulsifier, produces water-in-oil-in-water (W/O/W) multiple emulsions. The release rate of solute dissolved in the internal aqueous phase was measured using the dialysis technique. A theoretical model describing the diffusion of a multiple emulsion system was developed, which predicts the half-life for 50% of the internal solute to diffuse to the external phase. Experimental results showed the stability of multiple emulsions improved significantly upon using a thermodynamically stable microemulsion as a primary emulsion and a polymeric surfactant as a secondary emulsifier. As a resull, half-life of these multiple emulsions is greater than that of conventional multiple emulsions.