title: Synthetically simple, highly resilient hydrogels.
abstract: Highly resilient synthetic hydrogels were synthesized by using the efficient thiol-norbornene chemistry to cross-link hydrophilic poly(ethylene glycol) (PEG) and hydrophobic polydimethylsiloxane (PDMS) polymer chains. The swelling and mechanical properties of the hydrogels were controlled by the relative amounts of PEG and PDMS. The fracture toughness (G(c)) was increased to 80 J/m(2) as the water content of the hydrogel decreased from 95% to 82%. In addition, the mechanical energy storage efficiency (resilience) was more than 97% at strains up to 300%. This is comparable with one of the most resilient materials known: natural resilin, an elastic protein found in many insects, such as in the tendons of fleas and the wings of dragonflies. The high resilience of these hydrogels can be attributed to the well-defined network structure provided by the versatile chemistry, low cross-link density, and lack of secondary structure in the polymer chains.
authors.affiliation: Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States.
authors.forename: Jun
authors.initials: J
authors.lastname: Cui
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Lackey
authors.forename: Ahmad E
authors.initials: AE
authors.lastname: Madkour
authors.forename: Erika M
authors.initials: EM
authors.lastname: Saffer
authors.forename: David M
authors.initials: DM
authors.lastname: Griffin
authors.forename: Surita R
authors.initials: SR
authors.lastname: Bhatia
authors.forename: Alfred J
authors.initials: AJ
authors.lastname: Crosby
authors.forename: Gregory N
authors.initials: GN
authors.lastname: Tew
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D020100:Hydrogels / Q000138:chemical synthesis*; D019476:Insect Proteins / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D004129:Dimethylpolysiloxanes; D020100:Hydrogels; D019476:Insect Proteins; D011108:Polymers; D014867:Water; D011092:Polyethylene Glycols; C030951:resilin; C013830:baysilon