Ca²⁺ Enhanced Nacre-Inspired Montmorillonite–Alginate Film with Superior Mechanical, Transparent, Fire Retardancy, and Shape Memory Properties

Inspired by nacre, this is the first time that using the cross-linking of alginate with Ca ions to fabricate organic–inorganic nacre-inspired films we have successfully prepared a new class of Ca 2+ ion enhanced montmorillonite (MMT)–alginate (ALG) composites, realizing an optimum combination of high strength (∼280 MPa) and high toughness (∼7.2 MJ m –3 ) compared with other MMT based artificial nacre. Furthermore, high temperature performance of the composites (with a maximum strength of ∼170 MPa at 100 °C) along with excellent transmittance, fire retardancy, and unique shape memory response to alcohols could greatly expand the application of the mutilfunctional composites, which are believed to show competitive advantages in transportion, construction, and insulations, protection of a flammable biological material, etc.