Radiation effects on microcrystalline cellulose in 1-butyl-3-methylimidazolium chloride ionic liquid

► A new and convenient method to control average molecular weight of cellulose. ► Radiation degradation of MCC in ionic liquid was first studied by viscometry. ► The radiation degradation of MCC in [Bmim]Cl is attributed to numerous radicals. ► The content of MCC in [Bmim]Cl has negligible effect on degradation of cellulose. ► DMSO can efficiently inhibit the radiation degradation of cellulose in [Bmim]Cl.