Interphase enhanced low-velocity impact energy absorption in liquid crystal elastomer-based woven composites

Abstract

A reasonable approach to enhancing the energy absorption capability of composites is to incorporate elastomers that possess viscoelastic properties capable of enduring considerable elastic deformations and absorbing significant energy without fracturing. From this perspective, using liquid crystal elastomers (LCEs) as a matrix for fiber-reinforced composites could be an excellent option for developing impact-absorbing materials since LCEs possess an outstanding energy dissipation ability compared with amorphous elastomers. Herein, we report excellent energy-dependent impact properties of LCE composites reinforced with carbon fiber (CF) woven fabric. We discovered that the LCE/CF composite can effectively dissipate high amounts of low-velocity impact energy. The exceptional characteristics of LCE, which make it adaptable to impact energy absorption, combined with the presence of an interphase featuring a higher loss modulus compared to the individual composite components, were demonstrated to significantly enhance impact energy absorption of the composite. The developed LCE/CF composite panel is capable of absorbing up to 60 J of impact energy despite its thickness of only about 1 mm and has a substantial damping loss coefficient of about 0.1, which is two orders of magnitude higher than those of typical fiber-reinforced composites.