Strong and tough polyacrylamide/Laponite nanocomposite hydrogels modified with 1-butyl-3-methylimidazolium chloride salt

In this paper, the physicochemical double cross-linking nanocomposite hydrogels were prepared. Due to the addition of ionic liquid (1-butyl-3-methylimidazolium chloride salt), Laponite cannot spontaneously form a high thixotropic gel in water. The homogeneously dispersed Laponite nanosheets act as dynamic physical crosslinking sites, which cooperate with the chemical crosslinking center of MBA in the polymer chain segments and build a super-strong and super-tough hydrogel network structure. The PAM/Laponite/IL nanocomposite hydrogel achieves excellent tensile strength up to 1191 Kpa, a high tensile strain of 6842%, and a very high toughness of 26.62 MJ/m3. In this paper, an effective mechanism to enhance the mechanical properties of the hydrogel is proposed based on the structural evolution of Laponite. This highly flexible nanocomposite hydrogel shows excellent potential as a load-bearing material.