Starch based mechanically tough hydrogel for effective removal of toxic metal ions from wastewater

Abstract

Mechanically tough hydrogels have attracted incredible attention in numerous fields owing to their outstanding flexibility with extraordinary fatigue resistance. In this research, a new synthetic strategy was demonstrated to improve mechanical properties of starch grafted poly(acrylic acid) hydrogel by introducing a double cross-linked network. The design strategy includes the introduction of epichlorohydrin cross-linked starch into the poly(acrylic acid) chain. This cross-linked hydrogel possesses mechanical strength of 2.78 ± 0.58 MPa. More impressively, the hydrogel was also manifested noteworthy adsorption capacity for heavy metal ions for wastewater purification. Additionally, the hydrogel showed outstanding reusability due to its excellent mechanical strength. It has also prominent desorption ability to release the adsorbed metal ions from its network under the used condition. Thus, it was used for the subsequent cycles. This kind of mechanically strong bio-based hydrogel is promising as adept toxic heavy metal ions adsorbent, as it meets the demand for soft matter with remarkable mechanical properties to satisfy recyclability. Thus, the developed material may help to remove hazardous metal pollutants from contaminated water.