Performance improvement of poly(butylene adipate-butylene terephthalate) based nanocomposites modified by the cooperation of nano montmorillonite and ionic liquid

Abstract 1-hexadecyl-3-methylimidazolium chloride ionic liquid (IL) and sodium montmorillonite nanoclay (MMT) were used collaboratively to improve the properties of poly(butylene adipate-butylene terephthalate) (PBAT). Based on the ion exchange interaction and the shear effect during the melt blending process, effective exfoliation and uniform dispersion of MMT in the PBAT matrix have been achieved. The exfoliated nano MMT acted as heterogeneous nucleating agent and promoted the crystallization of PBAT, causing the melting and crystallization temperatures to shift towards higher temperatures. When the IL content was 3 wt%, the maximum complex viscosity and modulus was reached, and further increase of IL led to a decrease of the viscoelasticity due to the plasticizing effect of IL. For the same reason, the synergistic effect of MMT and IL achieved the optimum mechanical properties of PBAT/MMT/IL3 film. Furthermore, the excellent barrier performance of two-dimensional MMT nanosheets decreased the permeability of oxygen and water vapor of the nanocomposite films. Therefore, this work has a positive effect on promoting the application of PBAT in the packaging field.