Preparation and characterization of regenerated cellulose blend films containing high amount of poly(vinyl alcohol) (PVA) in ionic liquid

Regenerated cellulose/poly(vinyl alcohol) (PVA) blend films in ionic liquid 1-allyl-3-methylimidazolium chloride (AMIMCl) were successfully prepared by coagulating with water. The structures and properties were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). SEM images indicated that there was good compatibility between cellulose and PVA. The XRD results showed that the crystallinity of cellulose was significantly decreased from 42.8% up to 29.4% with increasing PVA content. The blend film with a 10 wt% PVA demonstrated the best mechanical performance. Its tensile strength and modulus showed 97 and 5,100 MPa, respectively compared with 69 and 3,400 MPa of neat cellulose film. The elongation also increased 50%. In addition, the transparency of the blend lms was still maintained well, and the shrinkage of the regenerated cellulose film was greatly improved with incorporation of PVA. The possible mechanism of forming cellulose/PVA blend films was proposed in the process of regeneration and dissolution. [graphic not available: see fulltext]