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1.
以乙二胺、月桂酸、三氯化磷和2-溴乙基磺酸钠等为原料,制备磺酸盐双子表面活性剂乙撑-双(N-乙磺酸-十二酰胺)钠盐,对其中间体合成工艺进行优化,对产物结构进行表征,并对其相关性能如表面活性、起泡性以及乳化性进行测定。结果表明:该表面活性剂的水溶液在24℃条件下,其临界胶束浓度(cmc)为0.53 mmol/L,相应表面张力(γcmc)为29.73 m N/m,该表面活性剂的表面活性、起泡性以及乳化性较好。  相似文献   

2.
以正辛酸、二乙烯三胺、环氧氯丙烷和亚硫酸钠为主要原料合成了一种氨基磺酸盐型两性表面活性剂3-双(辛酰胺乙基)氨基-2-羟基-1-丙基磺酸钠(BHS),用红外光谱、质谱和核磁共振谱图确证了产物的结构。该表面活性剂水溶液性能测试结果表明:25℃时临界胶束浓度(cmc)为5.2×10~(-4)mol/L,最低水/空气界面张力(γcmc)低至24m N/m。加入0.1mol/L Na Cl后,cmc减小至4.7×10~(-4)mol/L,γcmc降低至23.7m N/m。升高温度,cmc增加,γcmc下降。BHS的润湿性、乳化性能优于双辛酰胺乙基丙烷磺酸钠表面活性剂。  相似文献   

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以十二胺、1,6-二溴己烷和1,3-丙磺酸内酯为主要原料,分别采用极性头基加入法和联结基加入法,合成了一种磺酸盐型双子表面活性剂1,6-双(N-十二烷基-N-丙基磺酸钠)-己烷〔简称12-6-12(SO_3)_2〕。用1HNMR和ESI-MS表征了中间体和产物的结构,并考察了12-6-12(SO_3)_2的表面活性。结果表明:该表面活性剂水溶液在30℃下,临界胶束浓度(CMC)为0.015 mmol/L、表面张力为33.50 m N/m、表面过剩吸附量(Γmax)为2.78×10-6mol/m2、分子最小截面积(Amin)为0.60 nm2。该磺酸盐双子表面活性剂的CMC是结构相似的传统单链表面活性剂十二烷基磺酸钠(SDS)CMC(25℃,8.0 mmol/L)的0.2%,是结构相似的磺酸盐双子表面活性剂1,3-双(N-十二烷基-N-丙基磺酸钠)-丙烷(12-3-12(SO_3)_2)CMC(25℃,0.048 mmol/L)的31%。  相似文献   

4.
烷基四甲基胍双子表面活性剂的合成与性能   总被引:1,自引:1,他引:0  
以十二烷基伯胺和四甲基脲为原料合成了十二烷基四甲基胍及其盐酸盐.后者再与环氧氯丙烷反应制备了十二烷基四甲基胍双子阳离子表面活性剂,通过IR和~1HNMR鉴定了其结构,并考察了其性能.结果表明,十二烷基四甲基胍双子表面活性剂的临界胶束浓度(cmc)为2.5×10~(-4)mol/L,γ_(cmc)为28.5 mN/m,其表面活性明显高于单十二烷基胍盐酸盐.最后以十二烷基四甲基胍双子表面活性剂为模板剂制备了纳米SiO_2粒子.  相似文献   

5.
以二聚酸和N-甲基牛磺酸钠为原料,经酰氯化和Schotten-Baumann缩合反应合成了一种磺酸盐型双子表面活性剂,并对其相关性能进行了表征。结果表明,通过正交试验获得的磺酸盐型双子表面活性剂C34H66(CON(CH3)CH2CH2SO3Na)2的优化合成条件为:反应温度15℃,反应时间5 h,碱质量分数40%,n(N-甲基牛磺酸钠)∶n(二聚酸酰氯)=2.3∶1。合成的C34H66(CON(CH3)CH2CH2SO3Na)2具有更高的表面活性,其γcmc和cmc分别为30.4 mN·m-1和3.55×10-4mol·L-1。泡沫性能分析表明其具有良好的起泡性和稳泡性,水溶液的泡沫高度和半衰期分别是传统表面活性剂的1.3~3.2倍和12~33倍。  相似文献   

6.
以十二胺、1,6-二溴己烷和1,3-丙磺酸内酯等为原料,分别采用极性头基加入法和联结基加入法,合成了一种磺酸盐型双子表面活性剂1,6-双(N-十二烷基-N-丙基磺酸钠)-己烷(简称12-6-12(SO3)2 ),对其中间体和产物结构进行表征,并对其表面活性进行测定。1H NMR和ESI-MS的结构分析证实了它们的结构。性能测试表明:该表面活性剂水溶液在30oC条件下,临界胶束浓度(CMC)为0.015 mmol/L ,表面张力为33.50mN/m,表面过剩吸附量(Γmax)为2.78× 10-6 mol∙m-2,分子最小截面积(Amin)为0.58 nm2。该磺酸盐双子表面活性剂是结构相似的传统单链表面活性剂十二烷基磺酸钠(SDS)CMC(25oC,8.0 mmol/L)的0.002倍,是结构相似的磺酸盐双子表面活性剂1,3-双(N-十二烷基-N-丙基磺酸钠)-丙烷(12-3-12(SO3)2)CMC(25oC,0.048 mmol/L)的0.31倍。  相似文献   

7.
含松香骨架甜菜碱类两性表面活性剂的合成   总被引:4,自引:1,他引:3  
以脱氢枞酸为原料,合成了3种新型含松香骨架的甜菜碱类表面活性剂:N-(2-脱氢枞酰氧基)乙基-N,N-二甲基羧甲基甜菜碱,N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磺丙基甜菜碱和N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磷酸酯甜菜碱。通过红外和核磁共振氢谱对产物结构进行表征,3种甜菜碱cmc分别为3.16 mmol.L-1、3.01 mmol.L-1和2.56 mmol.L-1,此时表面张力分别为31.91 mN.m-1、33.20 mN.m-1和25.79 mN.m-1,说明3种甜菜碱具有好的表面活性。  相似文献   

8.
本文测定了四种双子表面活性剂(C12H25(CH3)2N+(CH2)1N(CH3)2CaH2w+1和C12H25(CH3)2NCH2CH2OCH2CH2N+(CH3)2CaH2m+1(分别记为C12-4-Ca和C12-CH2CH2OCH2CH2-Cm,m=12,18))的表面活性、乳化性能,并计算了表面过剩吸附量(Гmax)和单分予吸附面积(Amia)。结果表咧,合成的删种表面活性剂的临界胶束浓度(cmc)、相应的表面张力(γcmc)、Гmax和Amin基本相差不大。对称的双子表面活性剂的乳化性能优于非对称双子表面活性剂;具有刚性连接基团的乳化性能优于具有柔性连接拱团的双子表面活性剂。并考察了四种表面活性剂对28种植物常见致病菌的抑菌活性。  相似文献   

9.
以椰油醇聚氧乙烯(3)醚、氢氧化钠、2-氯乙基磺酸钠为原料合成了椰油醇聚氧乙烯醚磺酸钠表面活性剂(AESO)。通过正交试验设计考察物料摩尔比、反应温度、反应时间以及溶剂用量等因素对产物产率的影响,得到较佳工艺条件为:n(2-氯乙基磺酸钠)∶n(醇醚钠)=1.3∶1.0,反应温度70℃,反应时间3 h,溶剂甲苯50 mL,此时产率达70.3%,提纯后产物纯度达到98.65%。采用红外光谱和质谱对产物结构进行了表征,同时测定了产品的表面活性,结果表明,在25℃时cmc为3.2×10-4mol·L-1,γcmc为30.26 mN·m-1,表现出优良的表面活性。  相似文献   

10.
本文以二乙醇胺、溴代十二烷为原料合成N,N-二羟乙基十二烷基叔胺中间体,然后将N,N-二羟乙基十二烷基叔胺与聚乙二醇进一步反应合成聚乙二醇双子表面活性剂,得到一种既能降低表面张力,又能增加水相流动黏度的新型双子表面活性剂。通过红外光谱、热分析和产品性能评价,证实合成产物为季铵盐阳离子双子表面活性剂。聚乙二醇双子表面活性剂表面张力≤24m N·m~(-1),临界胶束浓度(cmc)≤5×10~(-5)mol·L~(-1)。室内驱油实验表明,采收率提高19%以上。  相似文献   

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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   

14.
A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by 1H MAS NMR. For direct comparison purposes, an SiO2 coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N2 absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.  相似文献   

15.
Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  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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