Flexible & Safe Heater: A Universal Approach To Control The Pyroresistive Behaviour Of Conductive Polymer Composites

With the rapid development of science and technology nowadays, all aspects of functionalities are supposed to be integrated into the smart materials in order to meet all the requirements of future products. Smart heating devices are throughout our lives, range from the ordinary heating machines, intelligent buildings, rail transits to the aircraft de-icing devices, they are dependent on self-controlled heating technology.

However, the traditional self-regulating heating device has a problem that cannot be overcome for a long time. That is, how to guarantee the stable self-regulating performance and at the same time have efficient Joule heating through the devices. Many different blends of materials have been shown to meet only one of these requirements, while it is difficult to achieve at the same time two contrary but equally important needs.

A recent study on this technical challenge has been carried out by the research team from the Queen Mary University of London, and the latest achievements have been published in Advanced Functional Materials. It shows us an extremely simple and practical tool and feasible solution that can be applied to a variety of materials systems. The work systematically studied the influence and performance of different materials, including graphene nanoplatelets and silver, coated glass spheres, on self-control temperature and self-heating function.

It has been demonstrated that the method successfully connected the materials with self-regulating temperature function and the material with self-heating function, solving the traditional challenges between the two functions. Moreover, through the use of more flexible polymer matrix, it also solves the limitation of the lack of flexibility of the conventional self-regulating heating device and broadens the application prospect of the new material system.

In this study, the universality of this approach was demonstrated both experimentally and theoretically by testing and modeling a number of devices with different connection configurations (in series or parallel) as well as different polymer matrices and conducting fillers. A tri-component series-connected heating device has been successfully developed and characterized, showing for the first time high PTC intensity combined with good Joule heating as well as mechanical flexibility. Experimental results from both externally heated tests and self-heating tests revealed that the pyro-resistive behavior was dominated by the conductive composites with high PTC intensity in the series connection.

This work also validates the versatility of different design methods under different material systems and achieves good repeatability and provides simple and feasible materials and design solutions for the next generation of self-control temperature devices. This work promises to have an impact in the field including healthcare, automotive, aerospace, domestic heating and de-icing train/rail.

The study, Universal Control on Pyroresistive Behavior of Flexible Self-Regulating Heating Devices was recently published in the journal Advanced Functional Materials.