A new term for technology—polymer sensors

In 2016, Professor Takao Someya of the University of Tokyo published an article titled "Plastic sensors will be the next development opportunity for polymer electronic materials" in Nature magazine. In the article, he raised the question "Can physiological function monitoring such as health sense human health like a car's self-check?"

The sensing that Someya mentioned refers to the sensors that are indispensable in today's electronic products. As a detection device, sensors are the basic components for realizing automatic detection and automatic control. With the development of science and technology, sensors are also constantly updated. Among them, influenced by emerging fields such as artificial intelligence and smart medical care, polymer sensors are gradually gaining attention .

Among the various types of polymer sensors, flexible pressure sensors are the most popular and are favored by many companies and research institutes. The market believes that wearable devices for health monitoring will bring development opportunities for flexible pressure sensors.

This is mainly related to the fact that people pay more attention to their physical health and start using wearable devices to monitor various physical health indicators in real time. People hope that wearable devices can be directly attached to the surface of the skin to obtain a series of health information such as blood pressure, blood sugar, pulse, etc., and collect this information into smart devices. After analysis and extraction, it helps doctors make diagnoses. In the process of achieving this goal, the biggest bottleneck is that traditional rigid inorganic integrated devices cannot fit and integrate with the flexible tissues of the human body to a high degree of closeness, and therefore cannot be accurately monitored. The birth of flexible pressure sensors will help change this situation.

Professor Someya first used semiconductor polymers for pressure sensors in 2003, but the flexible pressure sensors at that time still had problems such as low sensitivity, large minimum pressure response threshold, and slow response speed. In order to overcome these three major challenges, many teams continued to invest in research in the following years and achieved many breakthroughs in these three aspects.

In 2014, Nanjing University increased the sensitivity of flexible pressure sensors to a maximum of 133 kPa-1, the pressure response threshold to 0.8 Pa, and the response time to less than 47 ms by regulating the thin film micro-nanostructure through interface doping polymers. This research was cited by Professor Takao Someya of the University of Tokyo in a Nature Materials paper and evaluated as the highest sensitivity.

At the same time, people need wearable devices to monitor various body indicators in real time. In other words, wearable sensing systems are required to not only detect a single sensing signal, but also measure multiple signals at the same time. As a result, multi-mode sensors have emerged.

Back to Someya's question in the previous article - can physiological function monitoring such as health sense human health like car self-checking? The answer is yes. To achieve this goal, it is necessary to develop multi-mode flexible sensors and integrated systems such as physical, chemical, and biological. In this process, polymer sensors play an important role.