New microplastic-free encapsulation for more sustainable agriculture

Under the leadership of Prof. Dr. André Gröschel, Chair of Polymer Materials for Electrochemical Storage at the University of Bayreuth, and Prof. Dr. Frederik Wurm, Chair of Sustainable Polymer Chemistry at the University of Twente, the researchers succeeded in synthesizing fully degradable block copolymers based on polyphosphoesters, i.e. polymers that consist of two block-like segments and can therefore spontaneously form nanostructures. i.e. polymers that consist of two block-like segments and can therefore spontaneously form nanostructures So-called polymer cubosomes were formed from these polymers - microscopically small particles with a high internal order and pores of around 20 nanometers in diameter.

“We loaded these polymer cubosomes with fungicides during production,” explains Gröschel. “The loaded cubosomes are effective against gray mold, a common plant disease.” What is particularly remarkable is that the cubosomes continue to adhere to the leaves of grapevines after several simulated rains, releasing the fungicide continuously over several days. “We have been using DNA-inspired polyphopshoesters for drug delivery in medicine for over ten years, and now we have used these biodegradable materials for plant protection for the first time. This allows us to avoid microplastics in the environment,” explains Wurm.

Suna Azhdari, whose doctoral thesis made this breakthrough possible, emphasizes: “Compared to conventional, solid particles without pores, our polymer cubosomes show a significantly faster release of the active ingredient. This indicates a more effective application of pesticides, with less leaching of unused fungicide into the soil.”

A particularly important aspect of this innovation is the complete degradability of the cubosomes. “Our polymer cubosomes break down completely into harmless lactic acid and phosphate derivatives,” emphasizes Gröschel. “This makes them a promising, microplastic-free carrier system for crop protection products and underlines their potential for sustainable agriculture.” This development could make a significant contribution to a more environmentally friendly and efficient agriculture and at the same time offers a solution to the problem of microplastic pollution in agricultural applications.