Preparation of transparent cellulose film with controlled haze using halloysite nanotubes

In this study, a regenerated transparent film was obtained from cellulose/ionic liquid solution. The wrinkle and the optical properties of the film were controlled by mild heat conditionings and halloysite nanotube (HNT), respectively. To remove wrinkles, pretreatment and pressed-drying processes were employed. The haze of the film was increased with the increase of HNT, whereas the diffuse transmittance remained constant. As confirmed by FT-IR, SEM and rheological measurement, the HNTs were homogeneously dispersed in the film and formed hydrogen bonds with cellulose. Therefore, the study suggests methods that can be used to control wrinkling and haze to give transparent cellulose film.