Preparation Of Functional Cellulose Derivative Material By Ionic Liquid Assisted Modification

Cellulose is widely distributed in our nature.It has a lot potential in application because of its abundant reserve,renewability and low cost.However,cellulose hasn't been cosmically used in industrialization for its chemical structure.Cellulose is hard to dissolve in common solvents.To solve this problem,we select ionic liquid as solvent of pretreatment and combine ionic liquid and chemical modification to improve the modification of cellulose.We also studied the application of prepared cellulose derivative about the adsorption of metal ions,catalysis of biodiesel and antibacterial effect.We synthetize a series of alkyl phosphate ionic liquids by one step.We screen the optimum ionic liquid by testing the viscosity of ionic liquid and the solubilization of cellulose.The cellulose after treatment with ionic liquid changes into smaller particle with smaller diameter and the structure becomes loose.The characterization of cellulose demonstrates that there is no functional group introduced on cellulose.However,the structure has been changed.The crystal form of cellulose changes from cellulose?into cellulose?after treatment with ionic liquid.We prepared cellulose derivative with the method which combines ionic liquid and chemical modification.The prepared cellulose derivative can be used to remove Cu²⁺from aqueous solution.The adsorption process can be simulated with a pseudo-second order model and Freundlich isotherm model.The optimum pH for adsorption is 5.5,and the whole process can be almost completed quickly within 30 min.The maximum equilibrium adsorption capacity of sulfonated cellulose is109.27mg/g at 298.15K.We use cellulose derivative to catalyze the esterification of oleic acid.The whole process can be conducted under mild temperature.The optimum condition of esterification with sample SC is:methanol/oleic acid ratio:12:1,the amount of catalyst:5.0%,reaction time:8h,reaction temperature:60??The highest convention is 96.9%.The optimum condition of esterification with sample LSC is:methanol/oleic acid ratio:12:1,the amount of catalyst:2.5%,reaction time:8h,reaction temperature:60??The highest convention is 97.0%.Prepared cellulose derivative presents good catalysis in esterification.We also test the antimicrobial property of cellulose derivative.We select Escherichia coli and Staphylococcus aureus as models to test the antimicrobial property.The antimicrobial property on Escherichia coli of sample SC is 88.7%and the antimicrobial property on Staphylococcus aureus of sample SC is 46.2%.The antimicrobial property on Escherichia coli of sample LSC is 95.8%and the antimicrobial property on Staphylococcus aureus of sample LSC is 50.3%.In conclusion,we propose the idea that combines ionic liquid and chemical modification to improve the effect of modification.The prepared cellulose derivative can be applied in adsorption,catalysis and antibiosis.This study supplies the experimental data and technical support for the preparation of cellulose derivative,and also broaden the application of cellulose derivative in the fields of environment,energy and biomedicine.