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Cellulose is nature's most abundant natural polymer materials, biodegradable, and biocompatible good. Ionic liquids as room temperature molten salt, is a potential \It has been found that some ionic liquids can be well dissolved natural cellulose, and the reaction medium can be achieved in ionic liquids cellulose modified its function. The polyurethane material has excellent performance characteristics of a wide range of applications, but its biodegradability and biocompatibility, limit its further application. Accordingly, the present starting from the synthesis of ionic liquids studied the dissolution and regeneration of the microcrystalline cellulose in the ionic liquid, both the ionic liquid solution of cellulose in the polymerization and crosslinking of the cellulose with polyurethane prepolymer, synthesis of a cellulose-based polyurethane material, carried out a preliminary study of the structure and properties of the material. Main results are as follows: 1 Synthesis of Chloride 1 - butyl - 3 - methyl imidazole (Bmim] Cl), 1 - allyl-3 - methyl-imidazole ([Amim] Cl) chloride, chlorinated four kinds 1 - carboxyethyl -3 - methylimidazole and Gemini type ionic liquid, wherein [Bmim] Cl and [Amim] CL excellent solvent microcrystalline cellulose can be dissolved within a very short time microcrystalline cellulose prime, chloride 1 - carboxyethyl -3 - methyl imidazole with Gemini, ionic liquids can not dissolve microcrystalline cellulose. 2. Microcrystalline cellulose in the chloride 1 - butyl - 3 - methylimidazolium ([Bmim] Cl) dissolved regeneration process, the results show that, microcrystalline cellulose dissolved before and after any chemical reaction does not occur , is a physical process. Microcrystalline cellulose is dissolved in the ionic liquid after regeneration, microcrystalline cellulose crystal transition occurs, and its crystal form is the transition from cellulose I to cellulose II. Greatly reduce the degree of crystallinity of the microcrystalline cellulose regenerated prior to dissolution of the microcrystalline cellulose regeneration decreased thermal stability in the microcrystalline cellulose, microcrystalline cellulose has a higher residual amount of regeneration, regeneration micro crystalline cellulose surface structure is not dense. This work also uses three kinds of iso-cyanate (TDI, MDI, IPDI), and a polyether (N-220), to prepare three types of polyurethane prepolymer, and was dissolved in the ionic liquids ([Bmim] Cl) microcrystalline cellulose reactions, to prepare three types of cellulose-based polyurethane material. XRD results showed that the cellulose polyurethane material only at 2θ = 20.35 ° a single absorption peak, the crystal structure of cellulose has been destroyed. TGA results show that the cellulose-based polyurethane material has good thermal stability, which Cellulose/PU-1 has better thermal stability. The residual amount of the analyzed material, wherein Cellulose/PU-2 has a higher residual amount.
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