Economical Approach to Thermoelectric Cooling: Development of Conductive Polyethylene/Polypyrrole@Constantan Composite Using Extensional Rheological Technology

• • Electrical conductivity of 1699.8 S cm−2 and thermal conductivity of 13.9 W m−1 K−1 yield a ZT of 0.16 at 25 °C, surpassing typical conjugated polymers (~10–100 S cm−1) and enabling viable Peltier cooling without expensive inorganic semiconductors. • • The extensional rheological process produces a continuous conductive network at low filler content, reducing raw material costs and eliminating lengthy manufacturing steps associated with Bi2Te3-based devices. • • A thermoelectric device using PE/Ppy@iron achieved a 0.4 °C temperature reduction under 30 V/0.3 A DC; square-wave pulsed current stabilized cooling efficiency, and a custom insulation system reduced parasitic heat loss, achieving a total temperature reduction of 1.6 °C. • • The composite’s ZT of 0.16 at room temperature is approximately one-eighth that of vapor compressors, but the low-cost, scalable fabrication offers a commercially competitive alternative for niche cooling applications where fluoride refrigerants are prohibited.