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41.
Argan oil is well known for its nutraceutical properties. Its specific fatty acid composition and antioxidant content contribute to the stability of the oil and to its dietetic and culinary values. There is an increasing interest to use argan oil in cosmetics, pharmaceutics, and food products. However, the formulation of highly stable emulsions with prolonged shelf life is needed. In this study, argan oil‐in‐water (O/W) emulsions were prepared using microchannel (MC) emulsification process, stabilized by different non‐ionic emulsifiers. The effects of processing temperature on droplet size and size distribution were studied. Physical stability of argan O/W emulsions was also investigated by accelerated stability testing and during storage at room temperature (25 ± 2°C). Highly monodisperse argan O/W emulsions were produced at temperatures up to 70°C. The obtained emulsions were physically stable for several months at room temperature. Furthermore, emulsifier type, concentration, and temperature were the major determinants influencing the droplet size and size distribution. The results indicated that a suitable emulsifier should be selected by experimentation, since the interfacial tension and hydrophilic–lipophilic balance values were not suitable to predict the emulsifying efficiency. Practical applications: MC emulsification produces efficiently monodisperse droplets at wide range of temperatures. The findings of this work may be of great interest for both scientific and industrial purposes since highly stable and monodisperse argan oil‐in‐water emulsions were produced which can be incorporated into food, cosmetic, or pharmaceutical formulations.  相似文献   
42.
A core–shell latex comprising poly(butyl acrylate) as core and poly(styrene‐methyl methacrylate) as shell was synthesized by emulsion polymerization using allyloxy nonylphenoxy propanol polyoxyethylene ether ammonium sulfonate (ANPS) as emulsifier. Transmission electron microscope, differential scanning calorimeter, and thermogravimetric analyses suggested the prepared latex had a core–shell structure. The particle size of the core–shell latex was about 102.8 nm with a molar ratio of butylacrylate, methyl methacrylate, and styrene at 6 : 2 : 2, a mass ratio of ANPS and monomers, ammonium persulfate and monomers at 15% and 1.0%, respectively. The core–shell latex showed high centrifugal stability and excellent freeze‐thaw stability. The clogging nozzle rate of the pigmented ink containing 20 wt % core–shell latex was small, whereas the printed fabrics with this pigmented ink exhibited high rub and washing fastness. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
43.
以新型环保型APG 0810(烷基葡萄糖苷)乳化剂作为传统有毒APEO(烷基酚聚氧乙烯醚)乳化剂的替代品,采用预乳化-种子乳液聚合法制备了纯丙烯酸酯聚合物乳液。考察了APG 0810含量和聚合温度对预乳液稳定性、乳液黏度和冻融稳定性、胶膜表面性能和力学性能等影响。结果表明:当w(APG0810)=0.8%~1.5%(相对于乳液总质量而言)时,预乳液的储存稳定时间超过240 min;当w(APG 0810)=1.0%、聚合温度为88℃时,乳液黏度和冻融稳定性明显提高,胶膜综合性能相对最好。  相似文献   
44.
本文通过对乳化剂不同组合的研究,研制开发RD系列涂料印花浆消泡剂。该消泡剂不但具有优异的消泡抑泡效果,而且与印花浆料有良好的配伍性。  相似文献   
45.
采用预乳液连续滴加单体的聚合工艺,制成了一种具有较好持粘力、剥离强度的丙烯酸酯乳液压敏胶。探讨了乳化剂种类、乳化剂用量、单体组成等因素对聚合反应及胶粘剂性能的影响。  相似文献   
46.
新型可聚合乳化剂及其在乳液聚合中应用   总被引:3,自引:1,他引:3  
综述了可聚合乳化剂的分类、性能与应用,比较了可聚合乳化剂与传统乳化剂在乳液聚合中的优缺点,讨论了可聚合乳化剂的溶液性能,指出了可聚合乳化剂的发展趋势。  相似文献   
47.
合成了一种具有非离子和阴离子双重功能的乳化剂,研究了使用该乳化剂合成的聚醋酸乙烯酯乳液的性能,结果表明聚醋酸乙烯酯乳液的贮存稳定性和冻融稳定性有明显提高,固含量和粘度有增加,粘接强度有很大提高。  相似文献   
48.
The effect of highly hydrophobic emulsifiers, the palmitic sucrose ester P‐170 (hydrophilic/lipophilic balance (HLB) = 1.0), the stearic sucrose ester S‐170 (HLB = 1.0), the polyglycerol ester decaglycerol decastearate DAS 7S (HLB = 3.7) and the polyglycerol ester decaglycerol dodecabehenate DDB 750 (HLB = 2.6), on the nucleation of a high melting point milk fat fraction (HMF) and its blends with sunflower oil (SFO) was investigated by polarized laser light turbidimetry, X‐ray diffractometry and polarized light microscopy (PLM). Addition of polyglycerol esters accelerated nucleation, giving shorter induction times for the same supercooling. On the contrary, sucrose esters inhibited nucleation since induction times were elongated in all conditions selected. Addition of emulsifiers modified the polymorphic behavior in the blends with SFO. The β' form was promoted especially with the addition of S‐170. DAS 7S and DDB 750 promoted crystallization. PLM images showed many small crystals that did not appear in HMF images. Addition of P‐170 and S‐170 delayed nucleation and inhibited crystal growth. Crystals were notoriously smaller than the ones that appeared in HMF images. The Fisher–Turnbull model was used to calculate activation free energies of nucleation. In all cases, sucrose esters elevated the energy barrier for nucleation. Polyglycerol esters, however, if they had an effect on the energy barrier, lowered the values.  相似文献   
49.
采用乳化工艺制备了溴化丁基橡胶(BIIR)胶乳,研究了乳化剂种类、BIIR正己烷溶液浓度、乳化时间、乳化转速、胶乳体系pH值及蒸馏方式对BIIR胶乳的影响。结果表明,乳化BIIR的最佳条件为:BIIR正己烷溶液中BIIR质量分数为15.00%,体系pH值调节至11~12,高速剪切乳化时间为30 min,高剪转速为5 500~6 000 r/min,采用负压(压力为-0.04 MPa)旋转蒸馏,所得BIIR胶乳的蒸馏破乳率较低,且总固物质量分数可以达到45.00%以上;使用质量分数为20%的氯化钙溶液破乳成膜效果最佳。  相似文献   
50.
以甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、丙烯酸(AA)为功能单体和过硫酸铵为引发剂,采用不同的反应性乳化剂合成了固含量为50%~60%的丙烯酸酯无皂乳液。讨论了反应性乳化剂的种类及用量对无皂乳液性能及粒径等影响。结果表明:当反应温度为80~85℃、反应性乳化剂为烯丙氧基壬基酚聚氧乙烯硫酸铵(DNS-86)且w(DNS-86)=4%~5%时,无皂乳液的固含量高达60%左右、凝胶率几乎为零且粒径相对较小。  相似文献   
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