Mechanical Properties and Phase Transition of High Clay Content Clay/Poly(N-isopropylacrylamide) Nanocomposite Hydrogel

Abstract

Summary: A series of high clay content Clay-S/PNIPAAm nanocomposite hydrogels (S-N gels) has been successfully prepared by in situ polymerization. Their mechanical properties and phase transition behavior has been systematically investigated. It was found that S-N gels show high tensile strength, high elongation at break, fast stress relaxation, high hysteresis, and poor resilience, which may be ascribed to the hydrophilicity and flexibility of PNIPAAm chains. It was also concluded that the macroscopic phase transition behavior of S-N gels depend on the ratio of Segments II (thermosensitive segments) to Segments I (non-thermosensitive segments).