title: Radiation effects on microcrystalline cellulose in 1-butyl-3-methylimidazolium chloride ionic liquid.
abstract: The radiation processing of cellulose in ionic liquids (ILs) demands a comprehensive knowledge of radiation effects on cellulose in ILs. Herein, gamma radiation-induced degradation kinetics of microcrystalline cellulose (MCC) in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) was studied by viscometry. The intrinsic viscosity of MCC in [Bmim]Cl decreased slightly with increasing dose; while chemical structure and crystalline state of cellulose has no obvious change up to 300 kGy. The radiation degradation rate constant (k) of MCC in [Bmim]Cl was 2.60×10(-7)/kGy, lower than that of solid cellulose, but higher than that in N-methylmorpholine-N-oxide (NMMO) solvent. Furthermore, k value decreased to 1.12×10(-7)/kGy in dimethyl sulfoxide (DMSO)/[Bmim]Cl system due to the free radicals scavenging of DMSO. The radicals generated during irradiation play main role in the radiation degradation of MCC in [Bmim]Cl. This work provides a new way to control the average molecular weight of cellulose by radiation-induced degradation of cellulose in ILs.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, 100871 Beijing, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Hao
authors.forename: Jing
authors.initials: J
authors.lastname: Peng
authors.forename: Yinyong
authors.initials: Y
authors.lastname: Ao
authors.forename: Jiuqiang
authors.initials: J
authors.lastname: Li
authors.forename: Maolin
authors.initials: M
authors.lastname: Zhai
mesh_terms: D002482:Cellulose / Q000528:radiation effects*; D003037:Cobalt Radioisotopes; D005720:Gamma Rays; D007093:Imidazoles / Q000737:chemistry*; D007700:Kinetics; D058105:Polymerization; D012997:Solvents / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014783:Viscosity; D014961:X-Ray Diffraction
chemical_list: D003037:Cobalt Radioisotopes; D007093:Imidazoles; D012997:Solvents; C502841:1-butyl-3-methylimidazolium chloride; D002482:Cellulose; C109691:microcrystalline cellulose