双阳离子型离子液体的合成与性能

以N-甲基咪唑、吡啶和二溴代烷为原料合成了一系列α,ω-亚烷基-双(N-甲基咪唑)型和α,ω-亚烷基-双(吡啶)型离子液体,并对其结构、熔点、溶解性、吸湿性和热性能分别进行了表征.结果表明,随着连接两个阳离子联接基的碳氢链长度的增加,离子液体的熔点先降低后升高,联接基的碳氢链长度为5个碳原子时最低;α,ω-亚烷基-双(N-甲基咪唑)型离子液体的熔点低于α,ω-亚烷基-双(吡啶)型离子液体;双阳离子溴盐型离子液体溶于水,双阳离子六氟磷酸盐型离子液体溶于丙酮和乙腈等;双阳离子溴盐型离子液体有一定的吸湿性,所合成的双阳离子型离子液体具有较高的热稳定性.     

溴化1-十六烷基-3-乙烯基咪唑型离子液体的制备及聚合性研究

以N-乙烯基咪唑、溴代十六烷为原料,经亲核取代反应合成溴化1-十六烷基-3-乙烯基咪唑([HDVIM]Br)离子液体。并以该离子液体为单体,偶氮二异丁腈(AIBN)为引发剂,制备聚离子液体p[HDVIM]Br。采用红外光谱(FTIR)、核磁共振仪(~1H NMR)和元素分析、凝胶色谱仪(GPC)、热重分析仪(TGA)、X-射线衍射仪(XRD)及电导率对其进行结构与性能测试与分析。结果表明,[HDVIM]Br具有可聚性,且为无定形非晶结构。[HDVIM]Br的电导率随温度升高逐渐增大,随着浓度增加而增加;溴化1-十六烷基-3-乙烯基咪唑离子液体聚合物p([HDVIM]Br)的数均分子量为3.68×10~4 g/mol。     

咪唑型室温离子液体介质中甲苯氯甲基化反应的研究

在溴化N,N-二烷基咪唑型室温离子液体反应介质中,尝试了甲苯、多聚甲醛和氯化氢气体的氯甲基化反应。以[C5mim]Br为催化剂,考察了反应温度、反应时间和离子液体用量对反应转化率的影响,获得的较佳反应条件为:反应温度65℃,反应时间10h,离子液体催化剂用量为甲苯物质的量的4%,在此条件下甲苯的转化率为82.6%,单氯甲基化选择性为100%。随着溴化N,N-二烷基咪唑型室温离子液体烷基链的增长,甲苯转化率有所提高;以溴化N-十二烷基-3-甲基咪唑离子液体为催化剂时,甲苯转化率可达90%,单氯甲基化选择性为100%。反应结束后产物与离子液体自动分层,便于分离。离子液体催化剂重复使用6次,甲苯转化率保持恒定。     

1-烷基-3-甲基咪唑磺胺醋酰盐离子液体的合成

以甲基咪唑为原料,合成1-烷基-3-甲基咪唑溴盐中间体,与磺胺醋酰银反应,合成1-烷基-3-甲基咪唑磺胺醋酰盐离子液体,并研究其抑菌性能。考察投料比、反应温度对1-丁基-3-甲基咪唑溴盐中间体产率的影响;烷基碳原子数量对中间体的合成、离子液体的合成及其抑菌性能的影响。结果表明,n(N-甲基咪唑)∶n(溴代正丁烷)=1∶1.3,反应温度90℃时,1-丁基-3-甲基咪唑溴盐产率最高;烷基碳原子数量增加,中间体的产率逐渐变低,对离子液体合成产率及其抑菌性能影响较小。     

1-烷基-3-甲基咪唑磺胺醋酰盐离子液体的合成

以甲基咪唑为原料,合成1-烷基-3-甲基咪唑溴盐中间体,与磺胺醋酰银反应,合成1-烷基-3-甲基咪唑磺胺醋酰盐离子液体,并研究其抑菌性能。考察投料比、反应温度对1-丁基-3-甲基咪唑溴盐中间体产率的影响;烷基碳原子数量对中间体的合成、离子液体的合成及其抑菌性能的影响。结果表明,n(N-甲基咪唑)∶n(溴代正丁烷)=1∶1.3,反应温度90℃时,1-丁基-3-甲基咪唑溴盐产率最高;烷基碳原子数量增加,中间体的产率逐渐变低,对离子液体合成产率及其抑菌性能影响较小。     

溴化1-十六烷基-3-乙烯基咪唑型离子液体的制备及聚合性研究

以N-乙烯基咪唑、溴代十六烷为原料,经亲核取代反应合成溴化1-十六烷基-3-乙烯基咪唑([HDVIM]Br)离子液体。并以该离子液体为单体,偶氮二异丁腈(AIBN)为引发剂,制备聚离子液体p[HDVIM]Br。采用红外光谱(FTIR)、核磁共振仪(¹H NMR)和元素分析、凝胶色谱仪(GPC)、热重分析仪(TGA)、X-射线衍射仪(XRD)及电导率对其进行结构与性能测试与分析。结果表明,[HDVIM]Br具有可聚性,且为无定形非晶结构。[HDVIM]Br的电导率随温度升高逐渐增大,随着浓度增加而增加;溴化1-十六烷基-3-乙烯基咪唑离子液体聚合物p([HDVIM]Br)的数均分子量为3.68×101H NMR)和元素分析、凝胶色谱仪(GPC)、热重分析仪(TGA)、X-射线衍射仪(XRD)及电导率对其进行结构与性能测试与分析。结果表明,[HDVIM]Br具有可聚性,且为无定形非晶结构。[HDVIM]Br的电导率随温度升高逐渐增大,随着浓度增加而增加;溴化1-十六烷基-3-乙烯基咪唑离子液体聚合物p([HDVIM]Br)的数均分子量为3.68×10⁴ g/mol。     

酰胺功能化咪唑型离子液体的合成、性能及应用

合成了一系列含有酰胺片断结构的咪唑型离子液体,总收率达到51.8%~74.0%。用1HNMR、FTIR、元素分析、DSC、TG、黏度、溶解性和电化学等表征手段,对其结构组成和物理性质进行了全面的表征。结果表明:这些酰胺功能化咪唑型离子液体具有热稳定性高(在295.2℃以下不分解)、电化学窗口宽(4.0~4.2 V)、凝固点低(最低可达-76.5℃)等特点,并在极性溶剂中具有良好的溶解性。探讨了3-(N,N-二乙基氨甲酰基甲基)-1-甲基咪唑四氟硼酸盐(3 a)离子液体在缩醛(酮)化反应中的应用,获得了比传统离子液体1-正己基-3-甲基咪唑四氟硼酸盐(HeM ImBF4)更优的反应结果,转化率相对提高2%~17%。     

1-戊基-3-甲基咪唑类离子液体的合成

以1-氯戊烷和N-甲基咪唑为原料合成了室温离子液体1-戊基-3-甲基咪唑四氟硼酸盐(PMIMBF4)和六氟磷酸盐(PMIMPF6),通过考察各种影响因素对中间产物氯代咪唑盐(PMIMCl)的影响得出合成1-戊基3-甲基咪唑离子液体的最佳条件为:原料N-甲基咪唑与1-氯戊烷的投料比为1.2∶1,反应温度为70-75℃,反应时间为24 h。最终产物的收率为92%-94%。产物结构用FT-IR和1HNMR光谱进行表征。     

酸性离子液体催化合成N,N’-亚甲基双丙烯酰胺

以N-甲基咪唑、2-氯乙基苯、硫酸氢钾合成1-甲基-3-[α-甲基-(4-磺酸苄基)]咪唑硫酸氢盐酸性离子液体,考察了酸性离子液体在甲醛和丙烯腈反应合成N,N’-亚甲基双丙烯酰胺(MBA)中的催化性能。结果表明,合成MBA的最佳反应条件为∶n(甲醛)∶n(丙烯腈)=1.2∶1.0,酸性离子液体用量为丙烯腈质量的8.0%,反应温度70℃,反应时间2 h。在该条件下MBA的收率>92%,纯度为98%以上,且反应结束后,产物易于分离,酸性离子液体可循环使用5次以上。     

微波辐射下卤化1,3-二烷基咪唑离子液体的合成

采用未经改装的家用微波炉,在无溶剂的状态下以N-甲基咪唑(mim)为原料合成了系列卤化1-烷基-3-甲基咪唑离子液体,考察了微波功率、加热时间、加热方式、原料的物料比对产品收率的影响.用傅里叶红外光谱仪表征其结构,用沉淀滴定法测定了系列卤化1-烷基-3-甲基咪唑离子液体的相对分子质量.用微波辅助合成咪唑离子液体的方法无需密闭反应容器,避免使用有机溶剂作为反应介质,大大地缩短了反应时间,是实验室制备离子液体实用、有效的方法.     

六烷基胍TADC含能离子液体的合成与表征

采用离子交换法合成了4种六烷基胍4,5-二氰基-1,2,3三唑([Cn-guan][TADC],n=3,4,5,6)含能离子液体,用红外光谱和核磁共振对结构进行了表征,测试了其在常用有机溶剂中的溶解性,用表面界面张力仪和TG、DSC分别研究了其密度和热性能。结果表明,六烷基胍TADC离子盐在极性较大的有机溶剂中具有良好的溶解性,最大分解温度在370℃左右,表明[C3-6-guan][TADC]具有良好热稳定性,([Cn-guan][TADC],n=3,4,5)在DSC的二次升温过程中经历了玻璃态、过冷态、结晶固态和液态4种相态。     

Preparation and characterization of novel ionic liquid based on benzotriazolium cation

Six novel ionic liquids based on benzotriazolium ion were synthesized by an improved method. These ionic liquids were characterized by IR, ¹H NMR, and elemental analysis. Their melting point, thermal stability, conductivity, electrochemical window and solubility properties in common solvents were investigated. The results indicate that these ionic liquids show the higher thermal stability (up to 345 °C), the larger electrochemical window of 3 V, the peculiar solubility in traditional solvents and the excellent electrochemical medium in the electrochemical oxidation of naphthalene and ferrocene.     

己内酰胺类离子液体的热力学性质(英文)

A series of caprolactam ionic liquids(ILs) containing incorporated halide anions were synthesized.Their physical properties,such as melting points,heats of fusion and heat capacities,were measured by differential scanning calorimeter(DSC).The results indicate that these ionic liquids exhibit proper melting points,high value of heats of fusion,and satisfying heat capacities which are suitable for thermal energy storage applications.     

Thermodynamic Properties of Caprolactam Ionic Liquids

A series of caprolactam ionic liquids (ILs) containing incorporated halide anions were synthesized. Their physical properties, such as melting points, heats of fusion and heat capacities, were measured by differential scanning calorimeter (DSC). The results indicate that these ionic liquids exhibit proper melting points, high value of heats of fusion, and satisfying heat capacities which are suitable for thermal energy storage applications.     

Ionic liquids as active pharmaceutical ingredients

Ionic liquids (ILs) are ionic compounds that possess a melting temperature below 100 °C. Their physical and chemical properties are attractive for various applications. Several organic materials that are now classified as ionic liquids were described as far back as the mid-19th century. The search for new and different ILs has led to the progressive development and application of three generations of ILs: 1) The focus of the first generation was mainly on their unique intrinsic physical and chemical properties, such as density, viscosity, conductivity, solubility, and high thermal and chemical stability. 2) The second generation of ILs offered the potential to tune some of these physical and chemical properties, allowing the formation of "task-specific ionic liquids" which can have application as lubricants, energetic materials (in the case of selective separation and extraction processes), and as more environmentally friendly (greener) reaction solvents, among others. 3) The third and most recent generation of ILs involve active pharmaceutical ingredients (API), which are being used to produce ILs with biological activity. Herein we summarize recent developments in the area of third-generation ionic liquids that are being used as APIs, with a particular focus on efforts to overcome current hurdles encountered by APIs. We also offer some innovative solutions in new medical treatment and delivery options.     

Ionic liquids based on (fluorosulfonyl)(pentafluoroethanesulfonyl)imide with various oniums

New hydrophobic ionic liquids based on (fluorosulfonyl)(pentafluoroethanesulfonyl)imide ([(FSO₂)(C₂F₅SO₂)N]⁻, FPFSI⁻) anion with various oniums, including imidazolium, tetraalkyl ammonium, pyrrolidinium, and piperidinium, were prepared and characterized. Their physicochemical and electrochemical properties, including phase transitions, thermal stability, viscosity, density, specific conductivity and electrochemical windows, were extensively characterized, and were comparatively studied with the corresponding ionic liquids containing the isomeric but symmetric TFSI⁻ ([(CF₃SO₂)₂N]⁻) anion. These new FPFSI⁻-based ionic liquids display low melting points, low viscosities, good thermal stability, and wide electrochemical windows allowing Li deposition/dissolution. All these desired properties suggest they are potential electrolyte materials for Li (or Li-ion) batteries.     

Effect of alkyl chain length on the thermophysical properties of pyridinium carboxylates

In the present study,new series of pyridinium carboxylate protic ionic liquids (PILs) were synthesized by pairing pyridinium cation with carboxylate anion from C1-C3 forming pyridinium formate ([CsH6N+][HCOO-]),pyridinium acetate ([CsH6N+][CH3COO-]) and pyridinium propionate ([C5H6N+][CH3CH2COO-]) respectively.The physical properties namely,density,viscosity,surface tension (298.15-343.15) K,and refractive index (293.15-323.15) K were measured.Thermal properties namely,glass transition temperature,molar heat capacity,and thermal decomposition temperatures were also determined.The thermal expansivity was calculated using the experimental density data.The effect of increasing the alkyl chain length on the thermophysical properties of the pyridinium carboxylate PILs has been evaluated.As expected the physical properties i.e.density,viscosity,surface tension and refractive index of the investigated pyridinium carboxylates decreased with increasing temperature.In general pyridinium carboxylate PILs possessed low viscosity,high thermal stability and excellent hydrogen bonding capability,and these properties lead them to outperform conventional solvents employed for lignin dissolution.     

Measurement of thermal conductivity,viscosity and density of ionic liquid [EMIM][DEP]-based nanofluids☆

This article studied experimentally the effect of multi-wall carbon nanotubes(MWCNTs)on the thermo physical properties of ionic liquid-based nanofluids.The nanofluids were composed of ionic liquid,1-ethyl-3-methylimidazolium diethylphosphate [EMIM][DEP],or its aqueous solution[EMIM][DEP](1)+ H_2O(2)and MWCNTs without any surfactants.The thermal conductivity,viscosity and density of the nanofluids were measured experimentally.The effects of the mass fraction of MWCNTs,temperature and the mole fraction of water on the thermo physical properties of nanofluids were studied.Results show that the thermal conductivity of nanofluids increases within the range of 1.3%–9.7% compared to their base liquids,and have a well linear dependence on temperature.The viscosity and density of the nanofluids exhibit a remarkable increase compared with those of the base liquids.Finally,the correlation of the effective thermal conductivity and viscosity of the nanofluids was made using the models in the literatures.     

Effect of ionic liquids and surfactants on zinc oxide nanoparticle activity in crosslinking of acrylonitrile butadiene elastomer

The goal of this work was to study the influence of several ionic liquids and cationic surfactants on zinc oxide nanoparticle activity in sulfur vulcanization of acrylonitrile butadiene elastomer (NBR). In this article, we discuss the effect of ionic liquids and surfactants on the cure characteristics, crosslink density, and distribution in the elastomer network as well as on mechanical properties of the acrylonitrile butadiene rubber. Ionic liquids (alkylimidazolium salts) and cationic surfactants (alkylammonium bromides) decrease the vulcanization time of rubber compounds. Their application results in the increase of vulcanizate crosslink density as well as of the heterogeneity of elastomer network. The influence of ionic liquids on the acrylonitrile butadiene elastomer properties depends on the anion present in the molecule and on the length of alkyl chains attached to the imidazolium ring. The most active ionic liquids seem to be the ones with the 1‐butyl‐3‐methylimidazolium cation or the BF₄^‐ anion. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010