Nacre‐Inspired Nanocomposite Films with Enhanced Mechanical and Barrier Properties by Self‐Assembly of Poly(Lactic Acid) Coated Mica Nanosheets

Abstract Developing biodegradable materials such as poly(lactic acid) (PLA) is a promising strategy to reduce the reliance on non‐degradable plastics and the accumulation of those wastes. However, the fabrication of high‐performance biodegradable films which integrate excellent mechanical and barrier properties remains a major challenge. To address this problem, the “brick and mortar” structure, one of the most effective biomimetic models, is introduced to improve the comprehensive properties of materials. Here, a PLA‐assisted exfoliation and dispersion method to prepare the PLA coated mica nanosheets (Nano‐mica/PLA) from a natural mineral phlogopite is presented. By introducing the sheer force assembly, a kind of nacre‐inspired nanocomposite film with the “brick and mortar” structure can be fabricated. Such a nacre‐inspired nanocomposite film shows excellent mechanical properties, UV‐shielding, and gas barrier properties. The overall performance of the nacre‐inspired nanocomposite film is superior to commercial plastic films, which will allow it possible to break a path for practical applications of PLA in the field of packaging.