[20a-P1-1~11] 3.7 Laser processing

[20a-P1-9] The Stress-Strain Characteristics of Hydrogel Containing Metal Microstructure Fabricated by using Femtosecond Laser

〇Kosuke Mizuguchi¹, Manan Machida², Toshihiko Uemura², Mitsuhiro Terakawa^1,2 (1.Keio Univ., 2.Grad. Sch. Keio Univ.)

Keywords:femtosecond laser direct writing, hydrogel, stress-strain characteristics

Femtosecond laser direct writing enables the fabrication of 3D microstructures by multi-photon photoreduction of metal ions inside the hydrogel. The desired elasticity of base material is demanded owing to decrease damage to biological tissue and guarantee operation stability of the devices. Nevertheless, the elasticity of hydrogel will be influenced by fabricated metal microstructure inside itself. In this study, we fabricated silver microstructure inside a poly (ethylene glycol) diacrylate (PEGDA) hydrogel by using a 522-nm femtosecond laser and evaluated the elasticity of hydrogel containing fabricated silver microstructure by stress-strain curve. Stress-strain curve was determined by compression test. The elasticity of hydrogel containing silver microstructure is increased with increasing silver microstructures. In addition, the elasticity of the hydrogel containing silver microstructure changed when direction of fabricated silver microstructure changed. These results imply that the fabricated silver microstructure inside hydrogel blocked deformation of hydrogel network, and the mechanical strength of hydrogel containing silver microstructure increase more than natural hydrogel.