环境友好材料:基于氨基酸离子液体的理化性质与毒性研究

Environmentally friendly materials:Physico-chemical properties and toxicity of amino acid derived ionic liquids

制备了6种以氨基酸为阳离子的离子液体,并研究了熔点、玻璃转化温度、热稳定性、溶解性等重要的理化性质及毒性,为日后的应用奠定基础。结果表明,基Cl^(-)的离子液体熔点在90~100℃之间;而基于SO_(4)^(2-)的离子液体室温下为液态,无明显的熔点:符合"离子液体"的定义。仅一种离子液体有玻璃转化温度。6种离子液体在127~200℃之间发生了放热反应。所有的离子液体都能与水完全混溶,微溶或不溶于乙酸乙酯、正辛醇和乙醇。在毒性实验中,肌酸离子液体对螺旋藻的增殖无明显影响;L-组氨酸离子液体有一定的抑制作用,半数抑制浓度EC_(50)大于200 mg/L;甲硫氨酸离子液体有促进作用。所有的离子液体的GHS水生环境风险分类为第3级急性毒性或第4级慢性毒性,对环境的影响风险较小,可作为很好的环境友好材料。

6 Ionic liquids(ILs) were synthesized from 3 amino acids for cations and 2 inorganic acids for anions.Their physico-chemical properties,such as melting point,glass transition temperature and solvation property,as well as toxicity towards Spirulina platensis were studied.The melting points of Cl^(-) based ILs are between 90~100 ℃.The SO_(4)^(2-) based ILs are liquid at room temperature,without obvious melting points.Exothermal reactions took place between 127~200 ℃ All the ILs are fully miscible with water,slight soluble or insoluble in ethyl acetate,n-octanol and ethanol.Creatine based ILs have no obvious influence on the proliferation of Spirulina platensis.L-histidine based ILs inhibited the proliferation,with EC_(50) higher than 200 mg/L,whilst methionine based ILs stimulated that.The GHS Hazard to Aquatic Environment of all the ILs is categorized as classes Acute 3 or Chronic 4,corresponding to slight environmental hazard.Can be used as a good environmentally friendly material.