Smart conducting polymer composites having zero temperature coefficient of resistance

Area of Science:

• Materials Science
• Polymer Science
• Electrical Engineering

Background:

• Zero temperature coefficient of resistance (TCR) is critical for precise temperature control in heating elements and sensors.
• Existing research primarily focuses on inorganic materials, with limited development in polymeric zero-TCR systems.
• Polymer composites typically exhibit negative (NTC) or positive (PTC) temperature coefficients of resistance.

Purpose of the Study:

• To develop a novel hybrid conducting zero-TCR composite material using polymeric components.
• To achieve thermal stability and reliable temperature control through self-heating properties.
• To explore a polymer-based system with a near-constant resistance over a wide temperature range.

Main Methods:

• Fabrication of bi-layer composites combining a carbon nanotube (CNT)-based NTC layer and a carbon black (CB)-based PTC layer.
• Direct contact of the CB layer with electrodes for enhanced electrical stability.
• Experimental and theoretical validation of the composite's electrical resistance behavior under Joule heating.

Main Results:

• The developed hybrid composite demonstrated a near-zero TCR, maintaining resistance with less than 2% deviation up to 200 °C.
• The CB layer effectively buffered and distributed electrical current, stabilizing resistance changes.
• The unique zero-TCR behavior in a polymer-based system was confirmed through both experimental and theoretical analyses.

Conclusions:

• A novel polymer-based bi-layer composite with exceptional zero-TCR properties has been successfully developed.
• This material offers a promising alternative for applications requiring precise temperature regulation and high thermal stability.
• The findings represent a significant advancement in the field of functional polymer composites for electronic applications.