title: Self-healable, tough and highly stretchable ionic nanocomposite physical hydrogels.
abstract: We present a facile strategy to synthesize self-healable tough and highly stretchable hydrogels. Our design rationale for the creation of ionic cross-linked hydrogels is to graft an acrylic acid monomer on the surface of vinyl hybrid silica nanoparticles (VSNPs) for the growth of poly(acrylic) acid (PAA), and the obtained VSNP-PAA nanobrush can be used as a gelator. Physical cross-linking through hydrogen bonding and ferric ion-mediated ionic interactions between PAA polymer chains of the gelators yielded ionic nanocomposite physical hydrogels with excellent and balanced mechanical properties (tensile strength 860 kPa, elongation at break ∼2300%), and the ability to self-repair (tensile strength ∼560 kPa, elongation at break ∼1800%). The toughness and stretchability arise from the reversible cross-linking interactions between the polymer chains that help dissipate energy through stress (deformation) triggered dynamic processes. These unique properties will enable greater application of these hydrogel materials, especially in tissue engineering.
authors.affiliation: Laboratory of Advanced Materials (MOE), Department of Chemical Engineering, Tsinghua University, Beijing 100084, China. xxm-dce@mail.tsinghua.edu.cn.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhong
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Liu
authors.forename: Fu-Kuan
authors.initials: FK
authors.lastname: Shi
authors.forename: Li-Qin
authors.initials: LQ
authors.lastname: Zhang
authors.forename: Xi-Ping
authors.initials: XP
authors.lastname: Wang
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Cheetham
authors.forename: Honggang
authors.initials: H
authors.lastname: Cui
authors.forename: Xu-Ming
authors.initials: XM
authors.lastname: Xie
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D013718:Tensile Strength; D023822:Tissue Engineering
chemical_list: D000180:Acrylic Resins; D020100:Hydrogels; D007477:Ions; C006903:carbopol 940; D012822:Silicon Dioxide