Dual physically crosslinked double network hydrogels with high toughness and self-healing properties.

Toughness and self-healing properties are desirable characteristics in engineered hydrogels used for many practical applications. However, it is still challenging to develop hydrogels exhibiting both of these attractive properties in a single material. In this work, we present the fabrication of fully physically-linked Agar/PAAc-Fe3+ DN gels. These hydrogels exhibited dual physical crosslinking through a hydrogen bonded crosslinked agar network firstly, and a physically linked PAAc-Fe3+ network via Fe3+ coordination interactions secondly. Due to this dual physical crosslinking, the fabricated Agar/PAAc-Fe3+ DN gels exhibited very favorable mechanical properties (tensile strength 320.7 kPa, work of extension 1520.2 kJ m-3, elongation at break 1130%), fast self-recovery properties in Fe3+ solution (100% recovery within 30 min), in 50 °C conditions (100% recovery within 15 min), and under ambient conditions (100% recovery of the initial properties within 60 min), as well as impressive self-healing properties under ambient conditions. All of the data indicate that both the hydrogen bonds in the first network and the ionic coordination interactions in the second network act as reversible sacrificial bonds to dissipate energy, thus conferring high mechanical and recovery properties to the prepared Agar/PAAc-Fe3+ DN gels.

[1]  D. A. Gomes,et al.  Endothelial Differentiation of Human Stem Cells Seeded onto Electrospun Polyhydroxybutyrate/Polyhydroxybutyrate-Co-Hydroxyvalerate Fiber Mesh , 2012, PloS one.

[2]  Z. Suo,et al.  Highly stretchable and tough hydrogels , 2012, Nature.

[3]  Ming Zhong,et al.  Self-healable, super tough graphene oxide-poly(acrylic acid) nanocomposite hydrogels facilitated by dual cross-linking effects through dynamic ionic interactions. , 2015, Journal of materials chemistry. B.

[4]  Hyuntaek Oh,et al.  Autonomous self-healing of poly(acrylic acid) hydrogels induced by the migration of ferric ions , 2013 .

[5]  Lin Zhu,et al.  Fracture of the Physically Cross-Linked First Network in Hybrid Double Network Hydrogels , 2014 .

[6]  Qiuming Wang,et al.  A Robust, One‐Pot Synthesis of Highly Mechanical and Recoverable Double Network Hydrogels Using Thermoreversible Sol‐Gel Polysaccharide , 2013, Advanced materials.

[7]  T. Kurokawa,et al.  Double network hydrogels from polyzwitterions: high mechanical strength and excellent anti-biofouling properties. , 2013, Journal of materials chemistry. B.

[8]  Sang Yup Lee,et al.  Production of Poly(3-Hydroxybutyrate) by Fed-Batch Culture of Recombinant Escherichia coliwith a Highly Concentrated Whey Solution , 2000, Applied and Environmental Microbiology.

[9]  K. Shull,et al.  Ionically Cross-Linked Triblock Copolymer Hydrogels with High Strength , 2010 .

[10]  Xiaolong Wang,et al.  Molecularly Engineered Dual‐Crosslinked Hydrogel with Ultrahigh Mechanical Strength, Toughness, and Good Self‐Recovery , 2015, Advanced materials.

[11]  T. Kurokawa,et al.  A facile method for synthesizing free-shaped and tough double network hydrogels using physically crosslinked poly(vinyl alcohol) as an internal mold , 2010 .

[12]  Ting Huang,et al.  A Novel Hydrogel with High Mechanical Strength: A Macromolecular Microsphere Composite Hydrogel , 2007 .

[13]  S. Zwaag.  Self‐Healing Materials , 2007 .

[14]  T. Kurokawa,et al.  Double‐Network Hydrogels with Extremely High Mechanical Strength , 2003 .

[15]  Yuji Yamamoto,et al.  Design and Fabrication of a High-Strength Hydrogel with Ideally Homogeneous Network Structure from Tetrahedron-like Macromonomers , 2008 .

[16]  S. Van Vlierberghe,et al.  Biopolymer-based hydrogels as scaffolds for tissue engineering applications: a review. , 2011, Biomacromolecules.

[17]  Jian Ping Gong,et al.  Proteoglycans and Glycosaminoglycans Improve Toughness of Biocompatible Double Network Hydrogels , 2014, Advanced materials.

[18]  Kohzo Ito,et al.  Novel Cross-Linking Concept of Polymer Network: Synthesis, Structure, and Properties of Slide-Ring Gels with Freely Movable Junctions , 2007 .

[19]  T. Kurokawa,et al.  Direct Observation of Damage Zone around Crack Tips in Double-Network Gels , 2009 .

[20]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[21]  Wenbo Li,et al.  Hydrophobically associated hydrogels based on acrylamide and anionic surface active monomer with high mechanical strength , 2012 .

[22]  H. Cui,et al.  Self-healable, tough and highly stretchable ionic nanocomposite physical hydrogels. , 2015, Soft matter.

[23]  N. Peppas,et al.  Physicochemical foundations and structural design of hydrogels in medicine and biology. , 2000, Annual review of biomedical engineering.

[24]  Zhigang Suo,et al.  Strengthening alginate/polyacrylamide hydrogels using various multivalent cations. , 2013, ACS applied materials & interfaces.

[25]  Soft , 2019, The Missouri Review.

[26]  J. Gong,et al.  Highly Extensible Double‐Network Gels with Self‐Assembling Anisotropic Structure , 2008 .

[27]  Andrew G. Glen,et al.  APPL , 2001 .

[28]  J. L. López-Lacomba,et al.  Pseudo-double network hydrogels with unique properties as supports for cell manipulation. , 2014, Journal of materials chemistry. B.