DMSO as an auxiliary solvent in the fabrication of homogeneous chitin-based films obtaining from an ionic liquid process

[Display omitted] •Chitin and chitin-cellulose foils were prepared by a casting solution technique.•Preparation method using IL-based solvent with the assistance of DMSO was used.•Our method presented the improvement in the chitin processing in IL-based solvents.•All prepared materials were thoroughly investigated by selected research techniques.•The method provides the fabrication of composite materials with tunable properties. The novel preparation procedure for the fabrication of homogeneous chitin films has been designed. The method is based on the processing of biopolymers in ionic liquid-based solvents with the assistance of dimethyl sulfoxide co-solvent. In our experiments, co-solvent was added to the chitin solution just before biopolymer regeneration, as a viscosity reducer. The concept of the reduced viscosity allows to realize the easier manufacture of chitin compared to the method with chitin solution in neat IL solvent and additionally, it reduces the amount of an IL consumed for biopolymer dissolution. Furthermore, we investigated the preparation and characterization of chitin/cellulose composite films. The materials were obtained by mixing two separate solutions, chitin in IL and cellulose in IL/DMSO. The obtained foils were composed of designed weight ratios of chitin and cellulose, thus the properties of these materials were a hybrid of the features of the neat cellulose and neat chitin films.