A Nacre-Inspired Polymeric Multilayer Film With High efficiency of Low-temperature Toughening

Polypropylene (PP) films have been widely used in medical, electronics, and construction fields due to their low cost and excellent comprehensive properties. However, the poor low-temperature toughness of PP films restricts its further applications in extreme cold environments. Here, the nacre-inspired 8-, 32-, 128-, and 512-layer PP/SEBS-based films were constructed via our multilayer blown systems. Compared to the conventional blended films, 128-layer films showed significant improvement under the low-temperature conditions, i.e., 160 %, 150 %, and 136 % in impact toughness, tear toughness, and elongation at break, respectively. The high toughening efficiency of the multilayer films is because of the nacre-inspired multilayer structures, which can develop the multi-stage propagation of the damage behavior such as craze and plastic deformation to dissipate much energy when mechanically broken. Since nacre-inspired PP/SEBS-based multilayer films show high efficiency in low-temperature toughening, this work may provide a possible solution to improving the low-temperature mechanical properties of PP films or even other types of polymeric films.