Abstract:
Load-bearing applications of hydrogels include
soft robots, tissue engineering, and stretchable electronics. This
paper presents an extensive study of double network poly
(acrylic acid) based hydrogel on stress relaxation, compression
fatigue, shear stress, and shock absorption properties as a
potential load-bearing soft tissue replacement biomaterial.
Double network poly (acrylic acid) hydrogel was selected due
to simple processing and availability. The optimized
formulation of poly (acrylic acid) hydrogel was used for
samples preparation. The compression modulus varied with
hydrogel formulation, crosshead speed and swelled amount of
the hydrogel. Stress relaxation and shock absorption properties
of hydrogel were compared with polyurethane gel used in soft
insoles (Shore 5A). Developed hydrogel displayed good fatigue
properties up to 10,000 loading cycle at maximum stress of
390±30 kPa and at 84±4% strain. Further, maximum average
shear stress and shear modulus of 80 kPa and 140 kPa
respectively were observed at 84% strain before fracture