Super-tough double-network hydrogels reinforced by covalently compositing with silica-nanoparticles

• DOI: 10.1039/c2sm07233e
• Publication Date: 2012-04-27T08:32:36Z
• Authors: Qiang Wang; Ruixia Hou; Yajun Cheng; Jun Fu
• Keywords: 02 engineering and technology; 0210 nano-technology

We have successfully developed hydrogels with high compressive toughness by reinforcing the double-network structure (PAMPS/PAAm) grafted silica nanoparticles. Silica nanoparticles vinyl end groups were used as macro-crosslinkers to copolymerize AMPS, yielding a nanocomposite first network. Subsequent introduction of secondary PAAm network resulted in super-tough (DN) composite hydrogels, which do not fracture upon loading up 73 MPa and strain above 0.98. The strength, swelling behavior, morphology silica-grafted DN investigated functions nanoparticle content particle size, comparison nanoparticle-filled gels without covalent bonding polymer Maximal reinforcement was achieved at around 1 wt% (weight percent) respect AMPS. Unique embedded micro-network structures observed accounted for substantial improvement toughness. mechanism is discussed detail based on behavior these covalently composited hydrogels.