Facile strain analysis of largely bending films by a surface-labelled grating method

Area of Science:

• Materials Science
• Mechanical Engineering
• Soft Matter Physics

Background:

• Mechanical properties of flexible films are critical for stretchable electronics, wearable devices, and soft robotics.
• Current strain measurement methods rely on complex strain gauges, requiring extensive calibration and wiring.

Purpose of the Study:

• To develop a facile and accurate method for two-dimensional (2D) surface strain evaluation in largely bending films.
• To investigate the distinct mechanical behaviors of soft matter compared to hard materials.

Main Methods:

• Introduction of a novel technique utilizing surface-labelled gratings for 2D strain analysis.
• Application of the method to evaluate strain in liquid-crystalline elastomers and amorphous elastomeric films.

Main Results:

• Demonstrated a facile method for 2D surface strain evaluation in bending films.
• Revealed unconventional 3D bending in liquid-crystalline elastomers where both surfaces experience compression.
• Showcased the method's applicability to amorphous elastomeric films.

Conclusions:

• The surface-labelled grating method provides a valuable tool for mechanical evaluation of soft materials.
• This technique is essential for advancing the design of soft-matter-based electronic, photonic, and biointegrated materials.