Researchers from the University of Helsinki's Department of Chemistry have manufactured photochemically active polymers which can be dissolved in water or certain alcohols.

The effect where light causes the polymer to dissolve completely and be made visible can last several hours depending, for example, on the concentration of the solution. According to the scientists, this discovery is particularly significant for the development of new materials for optics and electronics.

In the study, a laser was aimed at a solution into which the polymer was partially dissolved. When exposed to light, the polymer switched to its cis conformation, dissolving completely and leaving a clear form which was visible in the cloudy solution.

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