title: High-Strength, Tough, Fatigue Resistant, and Self-Healing Hydrogel Based on Dual Physically Cross-Linked Network.
abstract: Hydrogels usually suffer from low mechanical strength, which largely limit their application in many fields. In this Research Article, we prepared a dual physically cross-linked hydrogel composed of poly(acrylamide-co-acrylic acid) (PAM-co-PAA) and poly(vinyl alcohol) (PVA) by simple two-steps methods of copolymerization and freezing/thawing. The hydrogen bond-associated entanglement of copolymer chains formed as cross-linking points to construct the first network. After being subjected to the freezing/thawing treatment, PVA crystalline domains were formed to serve as knots of the second network. The hydrogels were demonstrated to integrate strength and toughness (1230 ± 90 kPa and 1250 ± 50 kJ/m(3)) by the introduction of second physically cross-linked network. What̀s more, the hydrogels exhibited rapid recovery, excellent fatigue resistance, and self-healing property. The dynamic property of the dual physically cross-linked network contributes to the excellent energy dissipation and self-healing property. Therefore, this work provides a new route to understand the toughness mechanism of dual physically cross-linked hydrogels, hopefully promoting current hydrogel research and expanding their applications.
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.|Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Gong
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.|Department of Electronics Engineering, The Chinese University of Hong Kong , Hong Kong, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.|Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.|Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Jinhui
authors.initials: J
authors.lastname: Li
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.|Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Wangping
authors.initials: W
authors.lastname: Huang
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen, 518055, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Sun
authors.affiliation: Department of Electronics Engineering, The Chinese University of Hong Kong , Hong Kong, China.|School of Materials Science and Engineering, Georgia Institute of Technology , 771 Ferst Drive, Atlanta, Georgia 30332, United States.
authors.forename: Chingping
authors.initials: C
authors.lastname: Wong
keywords: H-bond; dual physically cross-linked network; hydrogel; self-healing; toughness