Synthesis And Study On The Application Of [Amim]Cl And[Hmim]HSO₄Ionic Liquids

As a kind of novel green solvents, ionic liquids are widely applied in many fields for their remarkable properties such as no vapor pressure, no poisonousness, no pollution, good capacity of dissolving most compounds etc. In this paper, synthesis and applications of alkyl imidazoles type ionic liquid were mainly researched. Surveyed the solubility property of [Amim]Cl and the catalytic of [Hmim]HSO4respectively.Firstly, synthetic [Amim]Cl and [Hmim]HS04ionic liquids in traditional and microwave radiation methods respectively. The synthesis conditions were optimized based on the single factor experiment and orthogonal experiment and its structure was determined by IR. Pyridinium was used as a probe molecule to analyze the acid-based type of [Hmim]HSO4.Then, Hammett indicator-UV-MS was used to characterize acid strength of [Hmim]HS04. The result was showed that [Hmim]HS04was both belong to Lewis acid and Bronsted acid.Secondly, dissolving behavior, dissolving ability of straw, cellulose acetate in discarded cigarette ends, prawn shell and collagen in [Amim]Cl were investigated. Aim at provide some reference to waste recycling and use of natural resources rationally. It was shown that [Amim]Cl can dissolve that four kinds of substances, and the straw had the highest rate of solubility, at100℃50min the rate of solubility can reach7.42%. Through the analysis’of FT-IR, dissolving behavior of products in [Amim]Cl were direct.Thirdly,[Amim]Cl ionic liquid as the medium, do collagen graft modification experiments. Methyl methacrylate was monomer, ammonium peroxydisulfate was initiator, and the synthesis conditions were optimized based on the single factor experiment and orthogonal experiment:reaction temperature was50℃, reaction time was4h, monomer was8%, initiator was0.6%. The percent grafting reached61.31%under this condition. By the analysis of FT-IR, the carbonyl peak of1736cm-1shown that reaction taken place between collagen and monomer.Lastly, ionic liquid replaced the traditional catalyzer, catalytic synthetic polylactic acid. There are three steps in the synthetic process which are free water removal, pre-polymerization and depolymerization. The optimal parameters of the process are: dehydrate at130℃,0.08MP and15min; microwave power of pre-polymerization setp was80W, vacuum0.095MPa,30min; in the third step, the condition of preparation of lactide was vacuum0.095MPa,240℃reduced pressure distillation2h. total mass of catalyzer was0.4%, in which nSn(oct)2:n[Hmim]HS04=1:3catalytic effect was the best. The yield of lactide was54%. Though FT-IR and H1NMR, determined its structure.The optimal parameters of the reaction process of PLA preparation are:lactide recrystalization for three times was as raw material, the mol mass of catalyst Sn(Oct)2was 0.15%mol..Microwave power was450W,30min. The max molecular weight of PDLLA prepared was18.67×104.