Stretchable, strong and self-healing hydrogel by oxidized CNT-polymer composite

Acrylamide hydrogel made from poly-acryloyl-6-amino caproic acid (PAACA) was reinforced with functional carbon nanotubes which strengthen composite four times more compare to PAACA, pure hydrogel. Oscillatory rheological experiments improved the special strength and reversible behavior of composite. Structure features and internal cross linking density of the composite were observed by allowing swelling and deswelling of composite in different pH solutions. The crack damaged composite was first self-healed autonomically with in a period of less than 3 min to a same strength observed by mechanical tensile testing. Later pH solution was introduced into crack damaged zone which re-healed the crack in a period of 1 min and strengthen the composite 15% (an average) more than that which re-healed without pH solution. This enhanced reinforcement performance and healing of composite hydrogel with pH solution refers to strong hydrogen bonding of the terminal groups across the interface and hydrophobic, hydrophilic interactions. (C) 2016 Elsevier Ltd. All rights reserved.