Effects of organic modified hectorite on performance, isothermal crystallization behavior and interface interaction of poly(lactic acid) film

In this work, in order to improve the properties of PLA, Hec-g@OA/PLA nanocomposite films were prepared by a single-screw extrusion film blown machine with PLA as a matrix and organically modified hectorite (Hec-g@OA) as a filler, and the optimum filler mass ratio of Hec-g@OA was preferred as an objective function of mechanical properties. The mechanical properties of PLA were found to increase from 24.31% to 61.75% when the mass percentage of Hec-g@OA was 0.3 wt%. Secondly, isothermal crystallization behavior of the nanocomposite films was analyzed by simultaneous rheology and FTIR technology for the purpose of further studied the effect of Hec-g@OA on the isothermal crystallization behavior of PLA, which showed that the half-crystallization time of Hec-g@OA/PLA decreased from 7.01 min, 28.99 min and 77.88 min to 3.87 min, 20.59 min and 65.78 min, respectively, at 130 °C, 135 °C and 140 °C. Finally, the form of the interaction between PLA and Hec-g@OA was analysis by electronic structure calculations and energy decomposition, it was analyzed that electrostatic interaction was found to be the main impact factor for induced crystallization of Hec-g@OA/PLA nanocomposite films, while induction and dispersion were found to be the minor impact factors.