Yielding Criteria of Double Network Hydrogels

• DOI: 10.1021/acs.macromol.5b02592
• Publication Date: 2016-02-12T20:13:22Z
• Authors: Takahiro Matsuda; Tasuku Nakajima; Yuki Fukuda; Wei Hong; Takamasa Sakai; Takayuki Kurokawa; Ung-il Chung; Jian Ping Gong
• Keywords: Brittleness; Internal energy; Extensibility

Double network (DN) gels, consisting of a brittle first and flexible second network, have been known to be extremely tough functional hydrogels. In DN gel subjected force, the breaks prior fracture network. This process, referred as internal fracture, dissipates energy increases required completely gels. Such macroscopically appears yielding-like phenomenon. The aim this paper is investigate relationship between yield point molecular structure gels more deeply understand mechanism To achieve goal, we synthesized having tetra-PEG which nearly ideal well-controlled gel. We found that yielding occurs when strands reach their extension limit (finite extensibility), regardless deformation mode. conclusion not only helps by further understanding toughening but also allows for design with precisely controlled mechanical properties.