Technological Innovation: The Appearance Of Healing Intelligent Discoloration Materials

 

Newly bought bags can change colors, clothes that are accidentally cut can heal like skin, car paint scrapes and water is brand new... These sci-fi movie like scenes are becoming reality.

Recently, the team of Feng Wei, a professor in the school of materials science and engineering of Tianjin University, has successfully developed new intelligent materials. This new material not only can change color, but also has the function of shape memory and self-healing. The study was selected as the cover article of German applied chemistry.

For polymer material scientists, the "adaptive color change camouflage ability" of many organisms in nature has always been a very important research direction. Based on the intelligent color changing and stealth mechanism of natural organisms, it is of great significance to develop new bionic intelligent color changing materials and technologies for production and life, national defense industry and other fields. At the same time, many polymer materials, such as rubber, plastics, coatings, fibers, etc., are important industrial materials. The annual wear consumption is huge. Improving the service life of advanced polymer materials can produce huge economic and social benefits.

Inspired by the intelligent color changing mechanism of chameleon in nature, the dynamic covalent borate bond was introduced into the main chain cholesteric liquid crystal elastomer. At the same time, the color and shape of the color changing film could be controlled by changing the temperature, Finally, we successfully developed a new type of intelligent material intelligent color changing liquid crystal polymer film.

The new material has a thickness of only 200 microns, which has the advantages of mechanochromic, shape programmable and excellent room temperature self-healing ability. It can change color when stretched; After being cut off, a few drops of water are added to the fracture surface, and the material can heal again after a period of time, thus having a longer service life. The material also has the "memory programming" property, which can be stretched into any two-dimensional or three-dimensional shape and remains unchanged. When the material is heated above the phase transition temperature, it can return to its original shape.

This research provides a simple and general method, which opens up the way for the development of intelligent bionic color changing camouflage materials, adaptive optical system and soft robot technology, and has great potential in clothing and packaging materials.