Multifunctional Rubber Latex Threads Based on MXene@Natural Rubber/Polyacrylamide for Temperature and Strain Sensors

The use of renewable resources in advancement of polymeric products is becoming increasingly relevant in the era due to the scarcity of fossil resources and threats from global warming. Herein, a cost-effective, eco-friendly benign route has been developed for the preparation of dual-network (DN) functional latex threads through natural rubber (NR), polyacrylamide (PAM), and MXenes. It is found that the NR/PAM/MXene (NPM) DN latex threads are highly sensitive to temperature changes, which can be exploited as a channel material for a thermal monitor. The NPM DN latex threads possess high flexibility and appealing mechanical performance, with a sensitivity as high as ∼2.0%/°C at the temperature range of −14.1–80 °C. Meanwhile, it can also work as a strain sensor at the working range of 0–200%. Large mechanical deformations, such as flexion with 180°, do not affect the electrical property. Good flexibility enables the latex threads to be woven into fabrics for practical temperature and strain detection. Remarkably, the thermal and strain sensitivities can be promoted by prestrain, enabling them to be programable. Latex threads with tunable sensitivity are superior to conventional materials that lack flexibility.