Poly (ethylene-co-methacrylic acid) (PEMA) ionomers and their applications including self-healing and shape memory applications

PEMA [poly (ethylene-co-methacrylic acid)] ionomer is a cost-effective, commercially important class of random copolymer of ethylene and methacrylic acid (3–15 mol %) where 15–80% of the acid groups are neutralized to form metal salts. Such PEMA ionomers carry great potential for use in a wide variety of unique applications such as shape memory, packaging materials, compatibilizers, toughening agent, and effective water vapor barrier material in organic devices and photovoltaic applications. Besides, due to their ‘self-healing’ property after impact, these materials have attracted special attention to the material scientists and technologists for their use in armour applications. The potential of self-healing materials to enable them damage-tolerant and also the load-bearing capability are promising aspects to develop lightweight functional structures to meet aerospace application requirements. This review introduces the state-of-the-art discussion of such novel ionomeric materials and their applications, especially on self-healing and shape memory materials. Indeed, this review first enlightens a deep understanding of the fundamentals of this class of materials with its electrostatic interactions within such ionic polymeric materials as well as highlights their extended functional applications.