Scratches on our cars can be irking, especially for luxury cars that can instantly lose their value. Now, a new paint created by Saarbrücken researchers could help repair these pesky scratches. The corn starch-based coating has a special arrangement of molecules that can repair small scratches by itself through moderate heat treatment. The material becomes flexible based on cross-linking, ring-shaped molecules, which compensates for the scratches and cause them to disappear.
The coating was created by INM experts and scientists from Saarland University.
The network structure of the lacquer is made from ring-shaped derivatives of corn starch called cyclodextrins. Polyrotaxanes are produced this way, and the cyclodextrins are threaded onto long-chain polymer molecules. This allows the cyclodextrins on the polymer thread to move freely across certain sections on the linear polymer where they can’t unthread by bulky stopper molecules.
“The resulting network is flexible and elastic like a stocking,” Carsten Becker-Willinger, head of the Nanomers program division at the INM, explains.
Once exposed to heat, the cyclodextrin rings move back along the plastic threads into the area where the surface is scratched, compensating for the gap formed by the scratch.
In order to make the substance weather resistance and obtain a higher mechanical stability, the INM scientists changed the composition of the polyrotaxanes by adding additional ingredients.
“As part of numerous application tests for different mixing ratios in combination with artificial weathering tests, we investigated pre-painted surfaces on which we applied the new coating as a topcoat,” chemist Becker-Willinger says.
Now, it is possible to remove micro-scratches in one minute at 200 degrees F. The scientists also accounted for the standard ISO guidelines of the paint industry.
“An industrial application is only conceivable if we fulfil these standard guidelines,” Becker-Willinger says.
The scientists hope to go from laboratory scale to pilot plant scale for the coating. This would allow the substance to be available for large-scale production. INM hopes to team up with different companies for their next step in development.
Filed Under: Product design