Description
Consisting of an interpenetrating structure with a highly stretched polyelectrolyte network (the first network) and a coiled network (the second network) of much lower stiffness, double-network gels exhibits salient mechanical properties, making it a promising candidate for various bioengineering applications. It is believed that the partial fracture of the first network, stabilized by the extension in the second network, is the main cause of the high toughness. Neutron scattering studies seem to suggest a special microstructure in the partially damaged state, whereas no direct observation could be made. In this research, inspired by the phase-field model of brittle fracture, we develop a numerical model that captures the partial damage in the first network to study the microstructural evolution in double-network gels. A checkerboard-like pattern with isolated islands of undamaged first network is observed in simulation. The dependence of the characteristic length scale on material properties and heterogeneity is further studied numerically. The formation of such microstructures might be the microscopic origin of the enhanced toughness in double-network gels.
Recommended Citation
Hong, W. (2014). Microstructural evolution in double-network gels. In A. Bajaj, P. Zavattieri, M. Koslowski, & T. Siegmund (Eds.). Proceedings of the Society of Engineering Science 51st Annual Technical Meeting, October 1-3, 2014 , West Lafayette: Purdue University Libraries Scholarly Publishing Services, 2014. https://docs.lib.purdue.edu/ses2014/mss/ssm/37
Microstructural evolution in double-network gels
Consisting of an interpenetrating structure with a highly stretched polyelectrolyte network (the first network) and a coiled network (the second network) of much lower stiffness, double-network gels exhibits salient mechanical properties, making it a promising candidate for various bioengineering applications. It is believed that the partial fracture of the first network, stabilized by the extension in the second network, is the main cause of the high toughness. Neutron scattering studies seem to suggest a special microstructure in the partially damaged state, whereas no direct observation could be made. In this research, inspired by the phase-field model of brittle fracture, we develop a numerical model that captures the partial damage in the first network to study the microstructural evolution in double-network gels. A checkerboard-like pattern with isolated islands of undamaged first network is observed in simulation. The dependence of the characteristic length scale on material properties and heterogeneity is further studied numerically. The formation of such microstructures might be the microscopic origin of the enhanced toughness in double-network gels.