The Study On The Synthesis Of Cellulose Acetate In Ionic Liquid System

The production of the cellulose acetylation has been used with a very wide range, such as textile, pharmaceutical, biotechnology, cigarette filter. The synthesis of cellulose triacetate in the acetic acid system was studied in this paper, the effects of factors such as kind and dosage of antioxidant, dosage of catalyst, n(cellulose structural unit):n(acetic anhydride), reaction temperature, and reaction time, were examined. The obtained optimum conditions were n(cellulose structural unit):n(acetic anhydride)1:3.3, cellulose10.3g, H2SO40.24g, antioxidant A0.006g, reaction temperature120℃and reaction time2.0h. Under the above conditions, the average degree of substitution and yield of cellulose triacetate were2.95and96.9%, respectively. The average degree of polymerization is more than160. Otherwise, the usage of antioxidant improved the color of the product.The production of the cellulose acetylation in the acetic acid system is with a low degree of polymerization. So9kinds of ionic liquids (ILs) were synthesized and characterized by FT-IR、1H-NMR and13C-NMR techniques. Choosing ionic liquids with good ability of dissolving cellulose [Bmim]Cl、[Amim]Cl、[C2OHmim]Cl and [C2OHmim][OAc]. And dissolution and regeneration of cellulose in the ILs were investigated by X-ray and SEM, analysis the changing of the structure of cellulose.The synthesis of cellulose triacetate in ILs system was studied.the effects of factors such as n(cellulose structural unit):n(acetic anhydride), reaction temperature, and reaction time, were examined. The obtained optimum conditions were n(cellulose structural unit):n(acetic anhydride)1:4.0, cellulose1.5g, reaction temperature130℃and reaction time5.0h. Under the above conditions, the average degree of substitution and yield of cellulose triacetate were2.96and more than96%, respectively. The average degree of polymerization is more than390. Otherwise, the usage of antioxidant improved the color of the product.In this paper, the synthesis of cellulose triacetate in the acetic acid system and in ILs system. The quality of the cellulose triacetate is very high.