A review of recent developments: self-healing approaches for polymeric materials

Abstract

The development and characterization of self-healing polymeric materials are now being considered for engineering applications. This is an emerging and fascinating area of research that could significantly extend the working life and improve the safety of the polymeric components for a broad range of applications. Overviews of various self-healing approaches for polymeric materials are presented in this paper. The approaches used to achieve healing functionality can be divided into three, such as microencapsule, microvascular, and intrinsic based healing system. Microencapsulation is a process of enclosing micron-sized particles of solids, droplets of liquids, or gases in an inert shell, which in turn isolates and protects them from the external environment. Microvascular based healing system can be partitioned in a manner similar to microcapsules base healing system in terms of the design cycle. Microvascular based healing system is known to give a significant improvement and overcome a few limitations present in the microcapsule embedded self-healing membrane design. Intrinsic based healing system is inherently able to restore its integrity which requires an external trigger for the self-healing to take place. This system is less complex than the microcapsule and microvascular based healing system in achieving repair through inherent reversibility of bonding of the matrix polymer. The development of polymers that can repair damage autonomously would be useful to improve the lifetime of polymeric materials. Success in the design of self-healing materials has important consequences on the material safety, product performance and enhanced fatigue lifetime.