Surfactant ionic liquid-based microemulsions for polymerization
作者:Feng Yan、John Texter
DOI:10.1039/b605287h
日期:——
Surfactants based on imidazolium ionic liquids (ILs), including polymerizable surfactant ILs, have been synthesized and used to stabilize polymerizable microemulsions useful for producing polymer nanoparticles, gels, and open-cell porous materials.
Low-Temperature AGET ATRP of Methyl Methacrylate in Ionic Liquid-Based Microemulsions
作者:Yinxia Zhou、Lihua Qiu、Zhijun Deng、John Texter、Feng Yan
DOI:10.1021/ma201545x
日期:2011.10.25
methyl methacrylate (MMA) with activators generated by electron transfer (AGETATRP) was done using microemulsion polymerization at the relatively low temperature of 30 °C. Ethyl 2-bromoisobutyrate (EBiB) was used as ATRP initiator, ascorbic acid (AA) was used as reducing agent, and CuCl2/N-bis(2-pyridylmethyl)octylamine (BPMOA) was used as catalyst. Microemulsion AGETATRP of MMA was well-controlled
使用微乳液聚合在30°C的相对较低的温度下进行了可持续的甲基丙烯酸甲酯(MMA)原子转移自由基聚合反应,该活化剂由电子转移生成的活化剂(AGET ATRP)进行。将2-溴异丁酸乙酯(EBiB)用作ATRP引发剂,将抗坏血酸(AA)用作还原剂,并将CuCl 2 / N-双(2-吡啶基甲基)辛胺(BPMOA)用作催化剂。MMA的微乳液AGET ATRP得到了很好的控制,生产了直径约5 nm且分子量分布窄的聚甲基丙烯酸甲酯(PMMA)纳米颗粒(M w / M n= 1.20-1.40)。在PMMA聚合和分离后,含有催化剂和ILs的混合物被证明是可回收和可循环使用的。补充引发剂,还原剂和单体(MMA)后,即使在第五个循环中,MMA的AGET ATRP仍可生产出分子量可再现且分子量分布窄的PMMA。因此,该过程被证明是可持续的。此外,使用新的表面活性剂IL配体,3- 11-[(3-(双(吡啶-2-基甲基)氨基)丙酰基)氧基]十一烷基}
Nanoparticle dispersions with ionic liquid-based stabilizers
申请人:Texter John
公开号:US20110233458A1
公开(公告)日:2011-09-29
The disclosure generally relates to a dispersion of nanoparticles in a liquid medium. The liquid medium is suitably water-based and further includes an ionic liquid-based stabilizer in the liquid medium to stabilize the dispersion of nanoparticles therein. The stabilizer can be polymeric or monomeric and generally includes a moiety with at least one quaternary ammonium cation from a corresponding ionic liquid. The dispersion suitably can be formed by shearing or otherwise mixing a mixture/combination of its components. The dispersions can be used to form nanoparticle composite films upon drying or otherwise removing the liquid medium carrier, with the stabilizer providing a nanoparticle binder in the composite film. The films can be formed on essentially any desired substrate and can impart improved electrical conductivity and/or thermal conductivity properties to the substrate.
PROCESSES FOR NANOPARTICLE DISPERSIONS WITH IONIC LIQUID-BASED STABILIZERS
申请人:EASTERN MICHIGAN UNIVERSITY
公开号:US20150086721A1
公开(公告)日:2015-03-26
The disclosure generally relates to a dispersion of nanoparticles in a liquid medium. The liquid medium is suitably water-based and further includes an ionic liquid-based stabilizer in the liquid medium to stabilize the dispersion of nanoparticles therein. The stabilizer can be polymeric or monomeric and generally includes a moiety with at least one quaternary ammonium cation from a corresponding ionic liquid. The dispersion suitably can be formed by shearing or otherwise mixing a mixture/combination of its components. The dispersions can be used to form nanoparticle composite films upon drying or otherwise removing the liquid medium carrier, with the stabilizer providing a nanoparticle binder in the composite film. The films can be formed on essentially any desired substrate and can impart improved electrical conductivity and/or thermal conductivity properties to the substrate.
A stimuli-responsive homopolymer poly(ILBr) is fabricated via a "two-phase" atom transfer radical polymerization (ATRP) process, where ILBr stands for the reactive ionic liquid surfactant, 1-[11-acryloylundecyl]-3-methyl-imidazolium bromide. An extraordinarily wide molecular weight distribution (PDI = 6.0) was obtained by introducing the initiator (4-bromomethyl methyl benzoate) in a heterogeneous two-phase process. The molecular weight distribution of poly(ILBr) was characterized by size-exclusion chromatography (SEC). The resulting homopolymer was found to be surface active and stimuli responsive. Poly(ILBr) films coated on quartz exhibit stimuli-responsive dewetting after ion exchange of Br- by PF6-. This dewetting phenomenon can be understood in chain segmental terms as a stimuli-induced structural relaxation and appears to be the first such reported stimuli-responsive polymeric dewetting. Titrating aqueous poly(ILBr) with aqueous bis(2-ethylhexyl)sulfosuccinate induces nanophase separation and results in the condensation of nanoparticles 30-60 nm in diameter.