Tough, highly stretchable and self-healing poly(acrylic acid) hydrogels reinforced by functionalized basalt fibers

Abstract

Recently, self-healing properties have lately received great attention for polymeric hydrogels which enables the hydrogels to restore their structures after damage and prolong the service life of the gels. However, commonly polymeric hydrogels generally exhibit poor mechanical and self-healing properties. Herein, hydroxyl-functionalized basalt fibers (f-BF) as reinforcement and methylene bis acrylamide as the crosslinking agent were introduced into poly(acrylic acid) (PAA) hydrogels for fabrication of mechanically robust and self-healing hydrogels. The enhanced PAA hydrogel was obtained through synergistic covalent cross-linking of PAA chains and dynamic crosslinking of hydrogen bond interactions between polymeric matrix and f-BF, which endow the resultant hydrogel excellent mechanical properties and self-healing ability. The PAA/f-BF double crosslink hydrogel exhibits high tensile strength of 108 KPa and excellent toughness of 344.23 KJ.m−3, almost ∼6 times to PAA hydrogel. The as-prepared hydrogel possesses highly stretchable of 813 %, ∼4 times to PAA hydrogel. What’s more, the as-prepared hydrogel also has enhance self-healing ability based on tensile strength reaches up to ∼85 %. The excellent performances and simple preparation should enable the development of self-healing hydrogels for potential tissue engineering and bionic robotics applications.