Preparation and properties of a form‐stable phase‐change hydrogel for thermal energy storage

In this study, we aimed to fabricate a form‐stable phase‐change hydrogel (PCH) with excellent mechanical properties and heat‐storage properties. Sodium alginate (SA) and polyacrylamide (PAAm) composite hydrogels were prepared with ionically crosslinked SA in a PAAm hydrogel network. Glauber's salt [i.e., sodium sulfate decahydrate (Na 2 SO 4 ·10H 2 O)] was incorporated within the hydrogel network as a phase‐change material. Scanning electron microscopy micrographs revealed that Na 2 SO 4 ·10H 2 O was confined in the micropores of the hydrogel inner spaces, and differential scanning calorimetry curves showed that the composite hydrogel possessed a considerable storage potential. Mechanical properties tests, such as tensile and compressive measurements, presented a decreasing trend with increasing Na 2 SO 4 ·10H 2 O dosage. We concluded that the prepared composite PCH could be used to design hydrogel materials with thermal‐energy‐storage applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43836.