Healable thermoset polymer composite embedded with stimuli-responsive fibres

Abstract

Severe wounds in biological systems such as human skin cannot heal themselves, unless they are first stitched together. Healing of macroscopic damage in thermoset polymer composites faces a similar challenge. Stimuli-responsive shape-changing polymeric fibres with outstanding mechanical properties embedded in polymers may be able to close macro-cracks automatically upon stimulation such as heating. Here, a stimuli-responsive fibre (SRF) with outstanding mechanical properties and supercontraction capability was fabricated for the purpose of healing macroscopic damage. The SRFs and thermoplastic particles (TPs) were incorporated into regular thermosetting epoxy for repeatedly healing macroscopic damages. The system works by mimicking self-healing of biological systems such as human skin, close (stitch) then heal, i.e. close the macroscopic crack through the thermal-induced supercontraction of the SRFs, and bond the closed crack through melting and diffusing of TPs at the crack interface. The healing efficiency determined using tapered double-cantilever beam specimens was 94 per cent. The self-healing process was reasonably repeatable.

Development of high shrinkage polyethylene terephthalate (PET) shape memory polymer tendons for concrete crack closure

“…10,11 A number of other investigators have explored the use of shape memory materials for closing, or preventing, cracks in a range of other materials. [12][13][14][15][16][17] The particular interest of the current work is large structural concrete applications, for which higher shrinkage stresses than those previously observed are required for the crack closure system to be viable. The shrinkage stress value sought is of the order of 100MPa but lower values, in the range 30-50MPa, would allow the system to close early age cracks and enhance autogenous healing mechanisms.…”

Polyurethane: A Shape Memory Polymer (SMP)

“…Selfhealing textiles are also developed using SMPU. In this context, Hu et al fabricated stimuliresponsive fiber using SMPU which showed 94% healing efficiency [65].…”

Healable and Optically Transparent Polymeric Films Capable of Being Erased on Demand

“…However, this method is not suitable for self-healing/healable films deposited on solid substrates. [20][21][22] Among various functional films, healable, optically transparent films are highly important but their fabrication remains a huge challenge. 1,15,23 Optically transparent films can find applications as protective and functional layers for various optical and display devices.…”