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1.
考察了十二烷基三甲基氢氧化铵(DTAH)和十二烷基苯磺酸钠(SDBS)及其混合体系的表面活性、碱性和稳定性。结果表明,复配体系n(DTAH)∶n(SDBS)=9∶1时,不仅降低表面张力能力和效率均有显著提高,而且具有很好的稳定性和强碱性,其CMC(临界胶束浓度)、γCMC(临界胶束浓度时的表面张力)和pH分别为3.02×10-5mol/L,28.10 mN/m和12.46,DTAH/SDBS复配体系在表面和胶束中的相互作用参数βσ和βm分别为-18.36,-22.69,表现出很好的协同作用。  相似文献   

2.
测定了N,N'-双(月桂酰基)乙二胺二丙酸钠(DLMC)及与十二烷基三甲基溴化铵(DTAB)和十二烷基聚氧乙烯(6)醚(AEO6)复配体系的表面张力,计算了DLMC及复配体系的表面化学性能参数;应用正规溶液理论得到复配体系内表面相和胶束相中2种表面活性剂之间的相互作用参数。结果表明,在25℃,0.1 mol·L-1NaBr水溶液中,DLMC的临界胶束浓度(cmc)为1.01×10-4mol·L-1,cmc下的表面张力(γcmc)为30.3 mN·m-1;DLMC/DTAB复配体系的γcmc,cmc和Amin均比单一组分要低;DLMC/AEO6复配体系的γcmc,cmc和Amin随着DLMC组分的增加先减小后有所增加。复配体系在形成胶束能力、降低表面张力效率及降低表面张力能力方面存在协同增效作用。  相似文献   

3.
以漆脂、环氧氯丙烷、二乙醇铵、1,4-二溴丁烷为原料,合成了一种漆脂基季铵盐双子表面活性剂。采用红外光谱、核磁共振碳氢谱对其结构进行分析,并对产物的表面性能进行分析。结果表明:合成产物临界胶束浓度(cmc)为5×10-4mol·L-1,表面张力(γ)可达33.6 mN·m-1;当质量分数为0.1%时,分出5 mL水的时间为10 min;表面张力和乳化性能与传统的十六烷基三甲基溴化铵(CTAB)相当。  相似文献   

4.
研究了烷基糖苷羟丙基磺酸盐阴离子表面活性剂(APGHPS)和咪唑啉两性离子表面活性剂(IMD)复配体系的稳定性、表面活性、泡沫性能、润湿性能和耐硬水性能。结果表明:APGHPS和IMD复配体系稳定性好;复配体系表现出良好的协同增效作用,当n(APGHPS)∶n(IMD)=1∶1时,增效作用最为明显,此时临界胶束浓度cmc=8.81×10~(-5)mol/L,最低表面张力γcmc=26.2 m N/m,均低于单一组分;复配体系的泡沫性能、润湿性能和耐硬水性能都较单一组分表面活性剂有所提高。  相似文献   

5.
双子型苯并咪唑阳离子表面活性剂的合成及性能   总被引:1,自引:0,他引:1  
以苯并咪唑、溴代正十二灴烧、二溴代烷烃为原料合成了3种双子型苯并咪唑阳离子表面活性剂,通过1HNMR和元素分析对合成的中间体和表面活性剂进行了结构表征.测试出该类表面活性剂的水溶液在70℃下的临界胶束浓度分别为2.9×10-3mol·L-1、4.5×10-6mol·L-1和2.6×10-6 mol·L-1;最低表面张力分别为37·6 mN·m-1、39.4 mN·m-1和39.7 mN·m-1.计算出对应的饱和吸附量分别为3.9×10-1mol·cm-2、3.6×10-11mol·cm-2、3.4×10-11mol·cm-2;饱和吸附面积分别为4.26 nm2、4.6 nm2、4.88 nm2.此外,还对合成的表面活性剂的克拉夫特点、各种溶剂中的溶解度、泡沫、乳化等性能进行了测试.  相似文献   

6.
一种酯型双子表面活性剂的合成及其协同效应   总被引:2,自引:0,他引:2  
通过酯化、溴代和季铵化反应,合成了以乙氧基为联接基的酯型双子(Gemini)阳离子表面活性剂N,N′-双(二甲基十二酸乙酯基)乙醚溴化铵([C11H23COOCH2CH2N (CH3)2CH2CH2OCH2CH2N (CH3)2CH2CH2OOCC11H23].2Br-,Ⅱ-12-EO2)。以表面张力法和稳态荧光法考察了Ⅱ-12-EO2与十二烷基硫酸钠(SDS)复配体系在40℃时0.1 mol.L-1溴化钠水溶液中的表面化学性质和胶束化行为。得到Ⅱ-12-EO2的临界胶束浓度(cmc)为1.25×10-4mol.L-1,最低表面张力(γcmc)为28.4 mN.m-1。采用稳态荧光法以芘(Py)为荧光探针,Ⅱ-12-EO2的胶束栅栏层的微极性,较一般表面活性剂大,达到1.4,与SDS的复配体系在1.2左右;以十二烷基溴化吡啶为猝灭剂,测定体系的胶束聚集数为15。运用非理想混合表面活性剂分子相互作用理论计算出Ⅱ-12-EO2与SDS复配体系的相互作用参数(β),复配体系具有降低表面张力效率、形成胶束能力和降低表面张力能力方面的协同效应。  相似文献   

7.
表面活性剂的复配及对甲维盐微乳剂物理稳定性的影响   总被引:1,自引:0,他引:1  
李嘉诚  冯玉红  林强 《精细化工》2005,22(Z1):70-72
通过测定不同类型的单一及复配型表面活性剂水溶液的临界胶束浓度和表面张力,研究了它对w(甲维盐)=1%的微乳剂物理稳定性的影响。膦酸酯类阴离子表面活性剂A的临界胶束浓度为1.79×10-4 mol/L,表面张力为28.90 mN/m;苄基酚聚氧乙烯聚氧丙烯醚嵌段型非离子表面活性剂B(EPE型)的临界胶束浓度为 1.91×10-4 mol/L,表面张力为20.70 mN/m;按m(A):m(B)=2:3形成的复配型表面活性剂2#的水溶液的临界胶束浓度为9.30×10-5 moL/L,表面张力为25.66 mN/m。当w(2#)=10%时,配制w(甲维盐)=1%的微乳剂物理稳定性最佳,各项指标均合格。  相似文献   

8.
为了提高植物生长调节物质1-萘甲氧基乙酸溶液的润湿性和渗透性,将其与碳氢碳氟表面活性剂进行复配。采用表面张力法测定复配体系的表面张力。结果表明,1-萘甲氧基乙酸复配体系的胶团生成能力、降低水表面张力的能力和效率均出现明显的增效。综合考虑cmcT(临界胶束总浓度)、γcmc、c20,T(表面张力比纯水降低20 mN.m-1时表面活性剂总浓度)及经济效益,全氟辛酸钠(SPFO)/十二烷基三甲基溴化铵(DTAB)/KCl复配体系的效果最佳(SPFO与DTAB摩尔比为1∶10,KCl为0.1 mol.dm-3)。这3个指标分别为3.1×10-4mol.dm-3、18.8 mN.m-1、9.2×10-6mol.dm-3。  相似文献   

9.
以十四酸、四甲基乙二胺为主要原料,制备了二聚甜菜碱型表面活性剂双[亚甲基二甲基(十二烷基羧酸钠基次甲基)]溴化铵(BQS - 14),用红外光谱和元素分析对产物结构进行了分析表征,并测试了其表面性能.结果表明,BQS - 14的临界胶束浓度(cmc)为0.30 mmol·L-1,临界胶束浓度下的表面张力( γcmc)为36.9 mN· m-1;BQS - 14与十二烷基磺酸钠复配产生了协同作用,当物质的量比为1:2时,cmc降为0.12 mmol·L-1,γcmc为31.0 mN·m-1;BQS - 14还具有较好的稳泡性能.  相似文献   

10.
以环氧氯丙烷和三甲胺制得活性中间体环氧丙基三甲基氯化铵(GTA),再将其和腰果酚进行反应得到了腰果基季铵盐表面活性剂(3-腰果酚氧基-2-羟基)丙基-N,N,N-三甲基氯化铵。采用IR和MS对产物结构进行了表征。通过单因素实验探索其较优合成工艺为:当GTA用量为0.05 mol时,溶剂乙醇用量30 mL,反应温度70℃,反应时间6 h,n(腰果酚)∶n(GTA)=1.2∶1,此条件下收率可达76.69%。采用表面张力法和电导率法分别测定了产品的临界胶束浓度(cmc),分别为6.38×10-3和6.36×10-3 mol·L-1,γcmc=38.86 mN·m-1。  相似文献   

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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.  相似文献   

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14.
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.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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