Thermomechanical Behavior of Carboxylated CNT/PDMS Composite

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Carbon nanotube (CNT) / polydimethylsiloxane (PDMS) composites are crucial for flexible electronics and sensors.
• The effect of operational heat on their mechanical performance is not well understood.

Purpose of the Study:

• To investigate the temperature-dependent elastic modulus of carboxylated CNT (c-CNT) / PDMS composites (CP).
• To understand the thermomechanical behavior and thermal stability of these composites.

Main Methods:

• Dynamic mechanical analysis was used to study the elastic modulus of c-CNT/PDMS composites.
• Systematic investigation of temperature-dependent mechanical properties.

Main Results:

• A critical temperature (T_c) was identified, above which the elastic modulus (E_CP) increases sharply.
• This increase is attributed to entropy elasticity and secondary crosslinking in PDMS.
• Carboxylated CNTs effectively reduce T_c and the modulus growth rate (δ_E) due to hydrogen bonding.

Conclusions:

• The thermomechanical behavior of c-CNT/PDMS composites is governed by a critical temperature related to PDMS crosslinking.
• Carboxylated CNTs improve the thermal stability of PDMS-based composites.
• Findings provide guidelines for applying these composites in varying thermal environments.