Korean researchers develop plastic that withstands 300 C and can be reshaped after hardening

South Korean researchers have developed a next-generation polymer material that can withstand temperatures of up to 300 degrees Celsius and be reshaped even after hardening. The material is expected to extend the lifespan of high-performance plastics used in extreme environments — such as aerospace and semiconductor applications — while reducing industrial waste.

The National Research Foundation of Korea announced Tuesday that a research team led by Yeo Hyeon-wook, a professor in the Department of Chemistry Education at Kyungpook National University, had developed a liquid-crystal bismaleimide (BMI)-based vitrimer combining ultra-high heat resistance with reprocessability.

Bismaleimide is a widely used thermosetting resin in the aerospace and electronics industries, valued for its high heat resistance and mechanical strength. Once cured, however, it forms a tightly cross-linked three-dimensional structure that is difficult to remelt or reshape, limiting its repairability and recyclability.

To address these shortcomings, the research team combined a rigid liquid-crystal molecular structure with dynamic covalent bond technology, in which covalent bonds exchange at high temperatures.

A vitrimer is a polymer material that maintains the robust structure of conventional thermosetting resins while allowing intermolecular bonds to rearrange at elevated temperatures, enabling reprocessing. The team achieved both high-temperature rigidity and reprocessability by using liquid-crystal bismaleimide together with diallyl bisphenol A, a functional compound.

The material recorded a glass transition temperature of 304.6 degrees Celsius — the point at which a polymer's molecular motion becomes active enough to alter its mechanical properties. The temperature at which 5 percent of the material thermally decomposes also reached 404 degrees Celsius, confirming high thermal stability.

The team also successfully ground the cured material into fine particles and applied heat and pressure to reconstitute it into a solid. Reprocessability and structural stability were most effectively balanced at 300 degrees Celsius, and key thermal and structural properties were largely retained after reshaping.

The technology is expected to find applications in fields that demand both high heat resistance and reusability — including aerospace composite materials, high-temperature electrical and electronic components, and insulating materials for semiconductor packaging.

The resource-saving potential could be significant if expensive high-performance materials can be repaired or reshaped without replacing components and if manufacturing scrap can be reused. However, the research team said actual application will require lowering the reprocessing temperature and time, verifying formability under large-area and composite conditions, and confirming long-term creep resistance and repeated durability.

"This research is meaningful in that it presents a molecular design strategy capable of simultaneously achieving high heat resistance and reprocessability," Yeo said. "Going forward, we plan to lower the reprocessing temperature and verify whether performance is maintained in actual composite materials and large-area components."

The findings, supported by the National Research Foundation of Korea, were published in Advanced Functional Materials, an international journal in the field of materials science.