Experimental design and testing of the electrothermal properties of carbon nanotube film

Electrically heated materials play a critical role in electrically heated textiles, which have potential applications in a wide range of fields for human healthcare. Among them, carbon nanotube film (CNTF) has gained a great deal of attention because of its excellent electrical and thermal conductivity. In this paper, we explored the electrothermal property of CNTF with different sizes and CNTF covered by polyester. It showed that the air temperature had a certain effect on the electrothermal performance of the CNTF. When a voltage of 2.5 V was applied, the 20 mm × 20 mm CNTF sample stored at 25°C achieved the highest temperature of about 37°C, which was 34°C when stored at −20°C. In addition, was observed that adding a polyester protective fabric can prevent heat loss effectively. When a voltage of 5.5 V was applied, the U-shaped CNTF achieved the highest temperature of about 42°C, while the polyester-CNTF achieved about 35°C. Notably, CNTF exhibited rapid temperature response when the voltages were turned on and off. When the voltage was 4.5 V, the 20 mm × 20 mm CNTF reached 50°C in 5 s, and the heating rate was about 10°C/s. When the voltage was turned off, the temperature dropped about 30°C immediately in 5 s. Finally, the relationship between the thermal conductivity of CNTF and its mass and specific heat capacity was constructed using Newton's law of cooling. This provided a model to calculate and predict the performance, which can help to design the power and temperature of electrical heated textiles in the future.