离子液体表面活性剂的合成与应用(Ⅻ)——微乳液

离子液体表面活性剂替代传统表面活性剂构建微乳液具有明显的优势,且结构可设计;所制备的微乳液分为单相微乳液和多相微乳液,其相图主要包括拟三元相图和"鱼状"相图;微乳液的微观结构,如液滴尺寸、相互作用或极性等,可通过电化学技术、动态激光散射、小角X射线散射等技术来确定。此类微乳液可广泛应用于纳米粒子制备、聚合反应、金属离子萃取等领域。     

壬基酚聚氧乙烯醚硫酸钠微乳液拟三元相图及微观结构研究

以表面活性剂壬基酚聚氧乙烯醚硫酸钠(NPES)为对象,考察了助表面活性剂与复配表面活性剂对NPES形成微乳液体系的影响.通过比较微乳液区域(ME)在拟三元相图中所占比例,发现最优配比为m(NPES):m(DBSA)=1:1,m(复配表面活性剂):m(正丙醇)=1:3,此时形成微乳液区域面积最大,占57%;用电导率法与动态光散射(DLS)分析微乳液结构,结果表明,当w(H2O)＞60%时,形成微乳液为O/W型,粒径为34 nm;该体系对温度不敏感.     

基于相图法的W/O型微乳液体系稳定性分析

以辛基苯基聚氧乙烯醚(TX-10)、十二烷基磺酸钠(SDS)和十六烷基三甲基溴化铵(CTAB)为表面活性剂,以正戊醇、正己醇和正庚醇为助表面活性剂,以正戊烷为油相,制备了油包水型(W/O)微乳液.用相图法分析了微乳液体系的热力学稳定性,计算了水核半径的大小,并考察了影响微乳液W/O区域范围的各种因素.结果表明:这几种微乳液体系在实验条件下能自发形成:微乳液的水核半径处于纳米量级,可作为制备纳米粒子的超微反应器;以TX-10为表面活性剂时,水核可以包容更多的水分子,微乳液的W/O区域较大;而以CTAB为表面活性剂时,由于其极性头之间的空间和静电排斥作用强,微乳液的W/O区域最小;以硝酸镧溶液作为分散相时,微乳液的W/O区域变化较小;随着温度的升高,微乳液的W/O区域显著减小.     

期刊文献

<正>抗菌性植物精油的复配及其微乳液的制备郭锦棠,余前峰,黄艳翠,郁培云,张瑾摘要:针对单一植物源杀菌剂存在高成本、低抗菌性且抗菌谱较窄及植物精油不稳定的问题,设计开发了一种新型的抗菌复方精油微乳液。采用协同指数法确定精油的最佳复配组合,并利用相转化法制备其微乳液,通过分析拟三元相图中微乳液区域的大小研究了表面活性剂、助表面活性剂、表面活性剂与助表面活性剂的质量比(Km)及油相含量对微乳液形成的影响。结果表明:在室温条件下,以丁香油-肉桂油-大蒜油复配精     

NMR方法在表面活性剂溶液研究中的应用

通过近年来ＮＭＲ方法在表面活性剂溶液研究中的具体应用实例，介绍了微乳液体体系各组分自扩散系数的ＮＭＲ测量和微乳液结构关系；表面活性剂溶液相图的ＮＭＲ确定；表面活性剂溶液增溶平衡和增溶作用ＮＭＲ研究等结果。     

柴油微乳液研制及影响因素的考察

利用非离子型表面活性剂复配制备W/O柴油微乳液,并以油、水、表面活性剂 助表面活性剂为三组分做出相图。通过微乳液相区面积考察不同因素对制备柴油微乳液的影响。因素包括不同表面活性剂的复配,不同的助表面活性剂及助表面活性剂与表面活性剂的比(m(C)∶m(T))。并用不同浓度的碱液代替水相,考察碱液对柴油微乳液形成的影响。结果表明最佳实验条件为:表面活性剂复配比为0.667,m(C)∶m(T)=0.3,助剂为正丁醇,碱液质量分数为0.1%。利用HLB值理论和界面膜理论对实验结果进行了分析。     

超临界二氧化碳微乳液的研究进展

系统地阐述了超临界二氧化碳微乳液的形成机理和概念,讨论了能形成超临界二氧化碳微乳液的表面活性剂和助表面活性剂的结构设计和选择。介绍了傅立叶红外光谱(FTIR)、电子顺磁共振(EPR)、核磁共振(NMR)、紫外可见光谱(UV-VIS)、X射线小角散射(SAXA)、中子小角散射(SANS)和动态光散射(DLS)等近代测试方法在超临界二氧化碳微乳液结构特性研究中的应用,并对超临界二氧化碳微乳液的研究应用进行了展望。     

汽油微乳液拟三元相图及电导率研究

以阳离子表面活性剂D0821和非离子表面活性剂AEO3的复配体系为研究对象，系统研究了D0821／AEO3-汽油-正丁醇-水体系一系列拟三元相图，并采用电导率法确定了微乳液结构。结果表明，表面活性剂D0821与AEO3不同复配配比对拟三元相图影响很大，随着阳离子表面活性剂D0821比例逐渐增加，液晶的面积按小一大一小的顺序变化；在D0821比例较大时，结构由W／O型微乳液→双连续→双折射→O/W型微乳液，随着表面活性剂含量降低，有大面积的乳液区出现；电导率的变化与相变化存在一致性。     

基于油茶籽油为油相的烟酰胺微乳制备及性能

以油茶籽油为油相、烟酰胺溶液为水相,制备油茶籽油-烟酰胺微乳。利用伪三元相图法和马尔文激光粒度仪研究微乳液的相行为、粒径,测定微乳液的防晒能力和体外抗氧化能力。结果显示：微乳液的最佳配方为复配表面活性剂司盘80与吐温80质量比为4∶1,聚乙二醇-400为助表面活性剂,复配表面活性剂与助表面活性剂质量比为1∶1,油茶籽油与混合表面活性剂质量比为6∶4。制备的油茶籽油-烟酰胺微乳中,烟酰胺溶液占微乳液总质量的8.34%。微乳液粒径为80 nm左右。在290～400 nm的紫外吸收峰数量多于油茶籽油,证明其防紫外线能力强于油茶籽油。微乳液对DPPH·、·OH、ABTS~+、O₂~-·均有抑制能力,表现出良好的抗氧化性能。为后续防晒制剂的开发提供理论依据。     

Gemini表面活性剂微乳液相行为的影响因素研究

研究了Gemini表面活性剂微乳液的界面相行为,考察了中间联接基团长度、表面活性剂和助表面活性剂的配比、醇链长和烷烃链长对相图的影响。结果表明：短链联接基团较易形成单相微乳液,表面活性剂用量较少且有较高的含水量;随着烷烃链长增加,形成O/W区域所需表面活性剂含量增加,且区域面积在逐渐减小;醇链长改变时,沿着油-（S＋A）轴都能形成W/O型微乳液。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。