Modified cellulose films with controlled permeatability and biodegradability by crosslinking with toluene diisocyanate under homogeneous conditions

Microcrystalline cellulose was modified by crosslinking with toluene diisocyanate under homogeneous phase in N,N-dimethylacetamide/LiCl solvent system. Modified cellulose films were prepared by solution casting method and their hydrophobicity, thermal stability, permeability, and degradability were characterized. The hydrophobicity, thermal stability, and mechanical properties of the films were improved by crosslinking according to the comprehensive results. The permeation rate of urea dropped rapidly from 107.7 mg/(cm2 h) to 0.88 mg/(cm2 h) with toluene diisocyanate/microcrystalline cellulose (TDI/MCC) increasing. Biodegradability of the films was examined in both controlled compost extract and natural cultivated soil. Comprehensive results including CO2 emission, scanning electron microscope (SEM) and attenuated total reflection infrared (ATR-IR) demonstrated that the films were biodegradable and the biodegradability decreased with TDI/MCC increasing. The results indicated that both permeation capability and biodegradability of the cellulose films can be optimized based on requirements.