Preparation and properties of carboxymethyl cellulose/layered double hydroxide bionanocomposite films

•Caboxymethyl cellulose and layered double hydroxides have attractive potential to develop bio-nanocomposites.•Increasing layered double hydroxide amount greatly improved mechanical properties of caboxymethyl cellulose films.•Incorporation of LDH significantly improved water vapor permeability of caboxymethyl cellulose films.•Relationships between bionanocomposite property and layered double hydroxide amount are reported.

Solution casting method was employed for preparing of carboxymethyl cellulose/layered double hydroxide (CMC–LDH) bionanocomposite films with LDH content ranged from 0 to 8 wt%. The synthesized nanocomposite films were characterized using FTIR, XRD, TEM and SEM analytical methods. XRD and TEM analysis revealed a partially exfoliated structure for nanocomposites with LDH content up to 3 wt%. However, for LDH contents higher than 3 wt%, nanocomposites formed an intercalated structure. Incorporation of LDH significantly decreased water vapor permeability (WVP) of the bionanocomposite films up to 37%. Addition of the LDHs into the CMC matrix is accompanied by a decrease in the film transparency. Mechanical properties of CMC-based films were improved significantly by addition of LDH particles. CMC–LDH nanocomposite film with 3 wt% LDH showed a 148 and 143% increase in the tensile strength and tensile modulus, as well as a 62% decrease in elongation in comparison with the pure CMC film.