China News Service, Hefei, November 30 (Reporter Wu Lan) The reporter learned from the University of Science and Technology of China on the 30th that the team of academician Yu Shuhong of the school was inspired by the natural mother-of-pearl structure to develop a new type of outer protective material for spacecraft—— Polyimide-nano mica composite film.

  According to reports, due to the unique bionic design of this new material, its mechanical properties and tolerance to extreme space environments have been significantly improved, and it is expected to replace the existing polyimide-based composite membrane materials.

  The results were published in the international journal "Advanced Materials" a few days ago.

  Polyimide film has become an excellent material for the "protective clothing" of space probes due to its excellent mechanical properties, excellent thermal stability and outstanding chemical resistance.

However, like other hydrocarbon polymers, this material is also extremely vulnerable to atomic oxygen attack in the space environment, resulting in a sharp decline in physical and mechanical properties. There is currently no good solution.

In addition, extreme environments such as cosmic ray radiation and space debris impacts also put severe tests on its stability.

  Inspired by the “brick-mud” layered structure of natural mother-of-pearl, the academician Yu Shuhong’s team used the previously developed nano-mica flakes with excellent mechanical properties and UV shielding function and can be prepared on a large scale as the building element, and the precursor of polyimide The polyimide-nanomica composite film is obtained by co-assembly of the body, and the superior intrinsic properties of mica are used to make up for the shortcomings of polyimide.

This design strategy not only achieves an effective improvement in the mechanical properties of the material, but also makes its upper surface more resistant to atomic oxygen, ultraviolet radiation, and space debris.

  Studies have shown that the tensile strength, Young's modulus and surface hardness of this new type of bionic composite film are 45%, 100% and 68% higher than those of pure polyimide film, respectively.

At the same time, its anti-ultraviolet aging and high temperature stability have also been significantly improved.

  The industry believes that the unique double-layer imitation mother-of-pearl structure design strategy proposed by this research provides new ideas for the design and construction of other high-performance nanocomposites.