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 well-controlled by the relative amounts of PEG and PDMS. 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.

Wide Bicontinuous Compositional Windows from Co-Networks Made with Telechelic Macromonomers

“…56,57,58 PEG and PS were chosen as model co-network components for several reasons. Many studies on PS-PEG block copolymers have been reported, and their phase behavior is well known.…”

Designing extremely resilient and tough hydrogels via delayed dissipation

“…We further implement the delayed dissipation and resilient domain by pre-stretching interpenetrating-network hydrogels to damage the short-chain network within controlled ranges, achieving extremely high resilience (~95%) and high toughness (~1900 J/m 2 ) (see Fig. 5 for comparison with counterpart biological and synthetic hydrogels [1,2,4,12]). Since the design principle and method reported here are material-independent, we expect they can be used to make existing tough hydrogels resilient and to design future tough and resilient hydrogels.…”

“…Designing synthetic hydrogels that are both tough and resilient will not only help the replacement and regeneration of relevant tissues such as heart valves, but also advance fundamental knowledge in mechanics and materials science. Despite the successes in developing hydrogels with high toughness [5][6][7][8][9][10][11] or high resilience [12,13], recent efforts on designing both tough and resilient hydrogels mostly focus on one property (e.g. reporting resilience without toughness) [14][15][16].…”

Guidelines for standardization of bioprinting: a systematic study of process parameters and their effect on bioprinted structures

“…These properties are a function of the material itself, as well as bioprinting process parameters ( Figure 1B). Printed tensile specimens have been used to investigate the interaction of lines and layers [9][10][11][12][13][14][15][16][17], however, a systematic investigation of how process parameters influence these properties has not been conducted. Terminology to describe the tensile measurements include two crucial aspects.…”