High-performance and readily processable biobased copolyamides for wearable self-powered sensors

Area of Science:

• Materials Science
• Sustainable Energy
• Polymer Chemistry

Background:

• Polyamides (PAs) are crucial for triboelectric nanogenerators (TENGs) due to their mechanical strength and wear resistance.
• Conventional PAs rely on petrochemicals, posing environmental concerns and hindering sustainable TENG development.
• There is a need for high-performance, processable, and eco-friendly materials for TENG applications.

Purpose of the Study:

• To synthesize a heat-resistant, biobased polyamide (PA56T) using sustainable monomers.
• To improve the processability of PA56T by incorporating aliphatic PA46, creating processable copolyamides (P-CoPAs).
• To evaluate the thermal, mechanical, and triboelectric properties of the developed P-CoPAs for TENG applications.

Main Methods:

• Synthesis of biobased PA56T using biobased 1,5-diaminopentane, 1,6-diaminohexane, and terephthalic acid.
• Screw processing of PA56T with aliphatic PA46 to create P-CoPAs, with P-CoPA-3 undergoing three processing rounds.
• Characterization of thermal properties (melting point, decomposition temperature) and triboelectric performance (open-circuit voltage, power density).

Main Results:

• P-CoPA-3 exhibited significantly enhanced melt flowability and processability after multiple processing steps.
• Key thermal properties (T_m = 273 °C, T5%d = 400 °C) and triboelectric output (V_oc ∼ 30 V) were largely preserved.
• The fabricated TENG demonstrated robust performance up to 200 °C, achieving a peak power density of 2380 µW m^-2.
• The device successfully powered 10 LEDs and charged capacitors, highlighting its practical energy harvesting capabilities.

Conclusions:

• This work presents a sustainable approach to developing high-performance, processable copolyamides for reliable energy devices.
• The biobased P-CoPAs offer a viable alternative to conventional polyamides, addressing environmental concerns in TENG manufacturing.
• The developed materials are suitable for applications in wearable self-powered sensors and other advanced energy harvesting systems.