Polyacrylamide/starch hydrogels doped with layered double hydroxides towards strain sensing applications

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Flexible electronics demand advanced materials for sensing.
• Hydrogels offer biocompatibility and flexibility but often lack conductivity.
• Layered double hydroxides (LDHs) are explored as conductive fillers.

Purpose of the Study:

• To explore the application of LDHs in conductive hydrogels for strain sensing.
• To fabricate and characterize polyacrylamide (PAM)/starch (St)/LDHs (PSL) conductive hydrogels.
• To evaluate the mechanical and sensing properties of the developed hydrogels.

Main Methods:

• Fabrication of PAM/St semi-interpenetrating network (SIPN) hydrogels.
• Incorporation of LDHs as inorganic nanofillers into the hydrogel matrix.
• Characterization of mechanical properties (elongation strain, fracture strength) and sensing properties (gauge factor).

Main Results:

• LDHs enhanced the mechanical strength of PAM/St SIPN hydrogels.
• The incorporation of LDHs endowed the hydrogels with electrical conductivity.
• PSL hydrogels demonstrated excellent mechanical properties (1750% elongation, 0.22 MPa fracture strength) and sensing capabilities (gauge factor of 2.73).

Conclusions:

• PSL hydrogels represent a promising material for strain sensing applications.
• The developed hydrogels show potential for use in human-computer interaction, flexible wearables, and soft robotics.
• LDHs offer an effective strategy for creating conductive and mechanically robust hydrogels.