Microplastics are ubiquitous and pose a growing environmental problem. Everyone has heard of the "plastic soup" in the oceans, where plastic waste breaks down into small particles that then end up in our food chain because plankton and marine animals consume the microplastics. Only a small part of the synthetic plastics is recovered or recycled after use. The majority is burned, ends up in landfill sites or ends up in the oceans, contributing to microplastic pollution. Based on the demand for sustainable alternatives, the GREENER project will develop bio-based and biodegradable polymers with the same properties as the widespread water-soluble polyacrylic acid. As a result, fewer microplastics end up in the environment, and only non-toxic, natural substances are released during degradation. The aim is to valorise these materials in the widest possible range of applications, from superabsorbents in concrete, biomedical materials, cosmetics, paper to coatings.