新型聚醚基三硅氧烷表面活性剂的制备及表面活性

以巯丙基三硅氧烷与聚乙二醇烯丙基甲基醚经thiol-ene反应合成了新型聚醚基三硅氧烷表面活性剂,并对其结构进行了FT-IR和~1H NMR表征,通过表面张力的测定考察了其表面活性。结果表明,该法可以高效合成高纯度的聚醚基三硅氧烷表面活性剂,该表面活性剂能将水的表面张力降低至21～23 mN/m,具有优良的表面活性。     

糖苷改性三硅氧烷表面活性剂及保湿性能

根据表面活性剂结构与性能的关系,将有机硅表面活性剂具有低表面张力的高"效能"与糖基表面活性剂的可生物降解性结合起来,合成了糖苷改性三硅氧烷表面活性剂,通过测定表面张力、临界聚集浓度、聚集体大小和保湿性研究了糖苷改性三硅氧烷表面活性剂的表面活性和在化妆品中的保湿性能。结果表明,糖苷改性三硅氧烷表面活性剂可以显著地降低水的表面张力至约20 mN/m,临界聚集浓度约为1×10-4mol/L,在水溶液中形成的聚集体平均水合半径约为250 nm。在化妆品配方中加入质量分数3%的糖苷改性三硅氧烷表面活性剂,使用2 h后水分含量为33.36%,水合率为31.97%,水分散失为11.21 g/(h.m2),水分散失率为-11.54%,具有明显的补水、锁水效果,且有持续的补水、锁水能力,是一种优良的化妆品保湿剂。     

双子型聚氧乙烯醚三硅氧烷表面活性剂的合成与性能研究

以烯丙基聚氧乙烯醚与六亚甲基二异氰酸酯为原料,在锡催化剂的作用下合成六亚甲基二氨基甲酸酯,然后在铂催化剂作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成反应制得双子型(Gemini)聚氧乙烯醚三硅氧烷表面活性剂(GPETS)。目标产物GPETS的结构用IR和1HNMR进行了表征,并研究了其表面活性。在浓度为5.9×10-5mol/L时,可以将水的表面张力降至22.0 mN/m。在不同的pH下研究其水解稳定性,并与相应的聚氧乙烯醚三硅氧烷表面活性剂对比,结果表明,GPETS的水解稳定性优于后者,适用于更宽的pH范围。     

烯丙基聚醚改性四硅氧烷表面活性剂的表面活性和润湿性能

通过1,1,1,3,5,7,7,7-八甲基四硅氧烷与不同聚合度的烯丙基聚氧乙烯醚反应合成了系列烯丙基聚醚改性四硅氧烷表面活性剂(TESE),用1HNMR和29SiNMR对产物进行了表征。通过对表面张力和接触角的测定,研究了其水溶液的表面活性以及在PET(聚对苯二甲酸乙二醇酯)和PMMA(聚甲基丙烯酸甲酯)基板上的润湿性能,同时探究了其在水中的溶解性以及亲水基结构(聚醚EO链长)对其表面活性和润湿性能的影响。结果显示,这类表面活性剂具有优异的表面活性和良好的润湿性能。随着EO链长的增加,TESE的表面活性存在最佳EO链长(EO单元数为8)。其中,在较短EO链长的一定范围内,TESE水溶液的最低表面张力(γcmc)变化幅度均较小,而EO链长超出一定范围后,γcmc增大幅度较为显著;TESE的润湿性能,在EO单元数小于12时变化不大,当EO单元数超过12时明显减弱。     

一种三硅氧烷硫酸盐表面活性剂的合成及性能

以1,1,1,3,5,5,5 -七甲基三硅氧烷(TSO)、甲基丙烯酸羟丙酯和氨基磺酸为原料合成了一种三硅氧烷硫酸盐表面活性剂;通过IR和1HNMR对合成的中间体及最终产物的结构进行了表征,并对其表面活性、泡沫性能和渗透性能等进行了测试.结果表明,三硅氧烷硫酸盐表面活性剂的最低表面张力(γcmc)为23.3 mN· m-1,临界胶束浓度(cmc)为3.16×10-2 tmol·L-1;该表面活性剂有较好的渗透性能,但是起泡性和稳泡性不强.     

阳离子型七甲基三硅氧烷双子表面活性剂的合成及性能研究

以丁炔二醇醚(BEO)和环氧氯丙烷为原料,在四氯化锡的催化作用下,开环醚化生成氯醇醚(BAE),然后与三乙胺发生季铵化反应得到季铵盐型氯醇醚(QASBAE)中间体,最后在铂催化剂的作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成反应生成目标产物季铵盐型阳离子型三硅氧烷双子表面活性剂(QASBTSS)。用FT-IR和1HNMR对目标产物的结构进行了表征,并通过测定其水溶液的平衡表面张力对其界面性能进行了研究。结果表明,在临界胶束为6.56×10-4 mol·L-1时,可以将水的表面张力降低至22.48 m N·m-1。     

葡糖酰胺基四硅氧烷表面活性剂的合成及其表面活性

利用含有双胺基的四硅氧烷中的伯胺基与D-葡萄糖酸-δ-内酯酰胺化,仲胺基与低聚乙二醇甲醚缩水甘油醚烷基化的反应,制备了含葡糖酰胺基的四硅氧烷表面活性剂(Me3SiO)3Si(CH2)3NR(CH2)2NHCO(CHOH)4CH2OH,R=CH2CH(OH)CH2O(CH2CH2O)nCH3,n=1,2,3;并用IR和1HNMR对其结构进行了表征,用表面张力法测定其表面活性。结果表明:这种含葡糖酰胺基的四硅氧烷表面活性剂在水溶液中的临界聚集浓度cac小于10-4mol.L-1,最低表面张力γ小于21 mN.m-1;随着分子中乙氧基(EO)数的增加,cac明显增大,但γ变化很小。     

三硅氧烷表面活性剂的合成、性能及应用

简要介绍了三硅氧烷表面活性剂的结构,同时比较了其与普通碳氧表面活性剂在水中的表面活性;阐述了不同类型(阳离子型、阴离子型、两性以及非离子型)的三硅氧烷表面活性剂的合成研究情况;并且对其表面/界面性能、聚集性能、超级铺展性以及稳定性进行了讨论;介绍了其在农业化学品、微乳液、涂料、印刷油墨和锂电池等方面的应用;最后提出了三硅氧烷表面活性剂目前存在的问题、发展方向和应用前景.     

季铵盐聚氧乙烯醚三硅氧烷表面活性剂的合成与界面性能

以烯丙基聚氧乙烯醚、环氧氯丙烷和氢氧化钠溶液为原料,采用两步法来合成烯丙基聚氧乙烯缩水甘油醚(APGE),然后在铂催化剂作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成反应制得聚氧乙烯基缩水甘油醚三硅氧烷(PGETS),最后将其与三甲胺盐酸盐进行开环反应合成出季铵盐聚氧乙烯醚三硅氧烷表面活性剂(QASPETSS)。用IR和1HNMR对目标产物的结构进行了表征,并通过测定该水溶液的平衡表面张力研究了其表面活性。结果表明,在临界胶束浓度为6.3×10-4mol/L时,可以将水的表面张力降至22.4 mN/m;饱和吸附量、饱和吸附层中每个QASPETSS分子所占的平均面积和形成胶束的标准自由能分别为3.6×10-6mol/m2、0.46 nm2和-28.2 kJ/mol。     

三硅氧烷表面活性剂复合体系对百树菊酯的增效研究

通过液体动/静态表面张力、铺展面积、接触角、药害等测试,研究了不同表面助剂对三硅氧烷表面活性剂(SE-90)进行二元及三元复配前后性能。结果显示:多种非离子表面活性剂能降低三硅氧烷表面活性剂的动态表面张力,其中具有较高HLB值的窄分布异构十三醇聚氧乙烯醚(9EO,S90)能显著提高三硅氧烷表面活性剂在动态中快速平衡水溶液表面张力的能力,且当w_(SE-90):w_(S90)=7:1时效果最佳;糖基表面活性剂SWE-30可显著降低三硅氧烷表面活性剂的药害,当w_(SE-90):w_(S90):w_(SWE-30)=7:1:2且总施药添加量为0.1%～0.033 %之间时,对5.7 %百树菊酯乳油的增效效果最理想。     

Mixed Micelles of Trisiloxane Based Silicone and Hydrocarbon Surfactants Systems in Aqueous Media: Dilute Aqueous Solution Phase Diagrams, Surface Tension Isotherms, Dilute Solution Viscosities, Critical Micelle Concentrations and Application of Regular Solution Theory

Mixtures of trisiloxane type nonionic silicone surfactant (SS) with sodium dodecylsulfate, tetradecyltrimethylammonium bromide or tert-octylphenol ethoxylated with 9.5 ethylene oxide groups were studied in water at 30 °C by dilute aqueous solution phase diagrams, surface tension and dilute solution viscosity methods. The cloud points for the silicone surfactant aqueous solutions increased upon addition of hydrocarbon surfactants indicating the formation of hydrophilic complexes in mixture solutions. The scrutiny of the surface tension isotherms plotted as a function of SS concentration revealed that competitive adsorption effects are the characteristic features in these mixtures depending upon the SS concentration. Otherwise the isotherms exhibited two break points and the difference of concentration between the two break points increased with the increase in SS concentration indicating the cooperative nature of interactions. The micellar mole fractions of individual surfactants were determined by Rublingh's regular solution theory; interaction parameters and activity coefficients were evaluated and interpreted in terms of synergistic type interactions in these mixtures. The surface active parameters in mixture solutions were estimated and their analysis shows that the molecular species in the mixture solutions have a preferential tendency for adsorption at the air/water interface than in association form in the bulk solution. The effect of hydrocarbon surfactants on the intrinsic viscosity of SS micelles was monitored and related to the enhanced hydration in mixed micelles.     

The Effects of the Organic Groups Attached at the Silicone Atoms of the Organosilane-Based Gemini Nonionic Surfactants on Their Surface Activities

A novel trisiloxane gemini nonionic surfactant was synthesized by the reaction of 3-(diethoxy(methyl)silyl)propan-1-amine with hexamethyldisiloxane to get 3-(trisiloxane)propan-1-amine, which was further reacted with glutaroyl dichloride to form the surfactant molecule, N ¹,N ⁵-bis(3-(trisiloxane)propyl)glutaramide (3). Some related compounds were also prepared, including N ¹,N ⁵-bis (3-(trimethoxysilyl)propyl) glutaramide (1), and N ¹,N ⁵-bis(3-(diethoxy(methyl)silyl)propyl)glutaramide (2). All prepared compounds were analyzed by IR, ¹H-NMR and ¹³C-NMR to confirm their structures. Their interfacial activities, including surface tension and wetting ability, were measured. These surface activities were compared each other and a discussion was carried out on how the organic groups attached on the silicone atoms affect their surface tension and wetting ability. To explain the superior surface activities of the molecules 3, a hypothesis was proposed about a cyclic hydrophobic core area that could be formed by the two hydrophobic chains and the linker of the gemini molecule due to the dispersion force (Van der Waals force) between the two trisiloxane moieties, which close the hydrophobic cycle inside the molecule.     

Synthesis and Properties of a Hydrolysis Resistant Cationic Trisiloxane Surfactant

In order to improve the hydrolysis resistant ability (HRA) of trisiloxane surfactants, a new kind of quaternary ammonium salt cationic trisiloxane surfactant (QASCTSS) was synthesized in three steps and investigated. The chemical structure of QASCTSS was characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. Compared with normal trisiloxane surfactants, QASCTSS exhibits a lower surface tension, especially under strong acid or alkaline conditions. This was attributed to the protection for Si–O backbone from the quaternized side chain, and some improvement in HRA is seen in acidic conditions with ethyl instead of methyl side chains on the quaternary structure.     

Aqueous solution properties of a silicone surfactant and its mixed surfactant systems

The aqueous solution properties of a nonionic silicone surfactant of dimethylpolysiloxane and its mixed surfactant systems were studied. It was found that the silicone surfactant has a high surface activity and forms micelles in two steps: premicelles in dilute concentrations and polymolecular micelles above 3.7 × 10⁻⁷ mol dm⁻³. In mixed systems of the silicone surfactant with anionic hydrocarbon or fluorocarbon surfactant, weak intermicellar interactions were found. They are due to electrostatic interaction between hydrophilic groups of the respective micelles. Dye solubilization measurements showed that the solubilized amount of Yellow-OB is greater than predicted by ideal systems. Hydrazo-azo tautomerism is observed in fluorocarbon-silicone surfactant systems, while Yellow-OB is solubilized only in the azo-form in the hydrocarbon-silicone surfactant system.     

Synthesis and Characterization of Glycoside-Based Trisiloxane Surfactant

The synthesis of glycoside-based trisiloxane surfactants of the general formula Me₃SiOSiMeR¹OSiMe₃ (R¹ = (CH₂)₃(OCH₂CH₂)₂OR², R² = glycosyl) is described, and the surface activity properties of the surfactant are studied. Diethylene glycol monoallyl ether glycoside is synthesized by reacting the diethylene glycol monoallyl ether with glucose. The glycoside-based trisiloxane surfactant is prepared by hydrosilylation of the precursor glycoside with hydrogen-containing trisiloxane. The product is structurally characterized by IR, ¹H NMR and MS. The surface tension of an aqueous solution is reduced to approximately 20 mN m⁻¹ at concentration level of 10⁻⁴ mol L⁻¹.     

Wetting of hydrophobic substrates by nanodroplets of aqueous trisiloxane and alkyl polyethoxylate surfactant solutions

Trisiloxane surfactants at low concentrations promote the complete and rapid wetting of aqueous droplets on very hydrophobic (hydrocarbon) substrates. This behavior has not been demonstrated by any other surfactant which explains why the trisiloxanes are referred to as superspreaders. Despite many experimental and theoretical investigations the mechanism of superspreading is not fully understood. Molecular dynamics simulations using all-atom force fields have been conducted to attempt to elucidate the mechanism of superspreading. Spherical nanodroplets containing approximately 10,000 water molecules in the bulk and 475 surfactant molecules at the liquid-vapor interface were placed in the vicinity of a graphite substrate and allowed to spread freely at room temperature. In the trisiloxane case the droplet was found to spread very little, although randomly removing 175 surfactant molecules lowered the final contact angle from 110^° to 80^°. In contrast, an alkyl polyethoxylate surfactant-laden droplet was found to spread significantly further, with the equilibrium contact angle reaching 55^°. Similar results for the two surfactant systems were found for cylindrical nanodroplets spreading on a self-assembled monolayer (SAM). The reasons for the lack of spreading in the trisiloxane case and the simulation challenges associated with these systems are discussed. In support of our arguments we demonstrate that the surfactant molecules of an initially uniform aqueous trisiloxane solution self-assemble into a bilayer in tens of nanoseconds on a graphite substrate. Lastly, in a final set of simulations, neat trisiloxane droplets at 450 K are found to arrange into a layered structure on a methyl-terminated SAM and to form a sand pile-shape on a hydroxyl-terminated SAM.