By Cameron Chai
A research study by Bartosz A. Grzybowski and his team at the Northwestern University has demonstrated that free radicals released from squeezed polymers produce substantial energy, which is capable of powering chemical reactions in water.
Bartosz A. Grzybowski
According to the team, this untapped energy can be exploited when polymers are under strain in normal conditions such as in car tires, shoe soles or even during squeezing plastic bags. The study findings have been reported in Angewandte Chemie. It also found that silicone polymers, materials widely utilized in cosmetic surgery implants, release a significant amount of adverse free radicals when they are under a reasonable amount of pressure, questioning the safety of some polymeric medical implants.
The research team is the first to harness this energy to induce chemical reactions by surrounding the squeezed polymer with water comprising desired reagents. It investigated seven different polymers. The free radicals generated in the polymer form hydrogen peroxide when they reach the water/polymer interface. The team also demonstrated that this hydrogen peroxide was able to induce chemical reactions such as dye bleaching, nanoparticle synthesis and fluorescence.
Grzybowski informed that the team is working on this project to utilize this unused energy to purify water in developing nations because hydrogen peroxide can destroy bacteria. The team corroborated that moderate squeezing or mechanical deformation produced substantial amount of free radicals in the polymers and the count of free radicals is roughly from the 10th to the 16th radicals for every cubic centimeter of polymer.
Approximately 80% of free radicals shifted into the surrounding solution, while the mechanical-to-chemical energy conversion efficiency was up to 30%, a value close to a car engine’s energy efficiency. Grzybowski explained that the study results proved that polymer-based medical implants can generate adverse free radicals, which in turn can cause diseases such as stroke, cancer, diabetes, myocardial infarction and other serious disorders. He concluded that a polymer can be harmful when implanted inside a human body but the same material can be a valuable source of energy when outside of it.