Chemical engineers at the University of Surrey in the United Kingdom have developed an experimental plastic material that turns directly into gas when heated.
The innovative polymer, known as poly(1,2-dithiolane), reverts back into its solid form upon cooling, presenting a potential breakthrough for industrial recycling and coating removal.
Details of the discovery were published in the scientific journal Macromolecules, which is published by the American Chemical Society. The study outlines a novel approach to manufacturing materials that can be easily recovered, reused, and processed without relying on complex chemical treatments.
Reversible sulfur bonds and sublimation
The new plastic is composed of 1,2-dithiolane units, which are molecular structures containing carbon, hydrogen, and two interconnected sulfur atoms. The key to the material's unique behavior lies in its reversible sulfur bonds, which allow the polymer chains to separate easily when exposed to mild heat.
Unlike conventional plastics that melt into liquid or degrade permanently, poly(1,2-dithiolane) sublimates at approximately 90 degrees Celsius. Sublimation is a phase transition in which a solid passes directly into a gaseous state without first melting into a liquid.
Researchers noted that this compound represents the first known example of a polymer exhibiting direct sublimation. Peter Roth, a chemical engineer at the University of Surrey, said the team demonstrated that it is possible to create a material that transforms into vapor at relatively low temperatures before naturally reconstructing as the exact same polymer when cooled.
Laboratory testing on paper and dyes
To test the practical utility of the material, the research team applied the polymer onto a rolled paper filter, creating an impermeable, waterproof layer around the surface. Applying a heat source allowed the scientists to completely remove the coating without needing any additional chemical processing.
Although the filter paper underwent a slight color change during the process, it successfully recovered its original capacity to absorb water. Furthermore, as the vaporized plastic cooled, its chemical components reassembled into solid polymer, demonstrating that the material can be captured and reused.
The team also conducted experiments to determine whether the technique could separate additives blended into plastics. Researchers mixed Nile red dye, a lipophilic chemical stain, into the polymer as a test substance. Heating the material removed the dye in a single step, bypassing the extra chemical steps typically required to extract additives from plastics.
Industrial potential and plastic recycling
Touseef Kazmi, a chemical engineer and the lead author of the study, said the most exciting aspect of the research was proving a scientific principle that had not previously been available. Kazmi added that adapting this specific chemistry could lead to new materials that are significantly easier to apply, remove, and recycle than current commercial plastics.
Researchers believe the vaporizing polymer could eventually be used in specialized industrial coatings designed to enhance insulation, lubrication, and resistance against moisture, corrosion, and physical wear.
Plastic waste remains one of the world's most urgent environmental challenges. Materials such as polyethylene, the most widely produced plastic globally, are extensively used in packaging, bags, and household items. The durability of traditional synthetic polymers makes them resistant to natural degradation, leading to persistent pollution across ecosystems.
Despite the promising findings, the Surrey research team clarified that poly(1,2-dithiolane) is currently an experimental compound. They emphasized that it does not yet serve as a direct replacement for conventional plastics or a comprehensive solution to global plastic pollution.
