Multifunctional carboxymethyl cellulose film by adjusting cellulose structure through molten salt hydrates

The functional and environmentally friendly materials derived from cellulose have attracted increasing attention due to their extensive application. In this work, a new approach for preparation of carboxymethyl cellulose (CMC) films by adjusting the structure of cellulose with molten salt hydrates (MSHs) was proposed. The dissolving ability of cellulose in single and mixed MSHs was studied, and the structure of regenerated cellulose was characterized. The mechanism of cellulose dissolution and regeneration revealed that cellulose regenerated from mixed MSH (LiCl–2ZnCl2–6H2O) was conducive to derivatization. CMC films were synthesized from regenerated cellulose, and their structure–property relationships were investigated. CMC films with good mechanical strength and transmittance and CMC-H films with water resistance and flexibility were successfully prepared, illustrating that adjusting cellulose structure by using MSHs is an effective strategy for developing multifunctional CMC films. [Display omitted] •A new approach for preparation of CMC film was proposed.•Cellulose regenerated from mixed MSH was conducive to derivatization.•CMC film with good mechanical strength and transmittance were prepared.•CMC-H film with water resistance and flexibility was obtained.