Cellulose is the most common biopolymer in the world, which can replace fossil-based plastics and fibers. However, cellulose-based plastics only account for 0.2% and man-made fibers for 1% of the world's production of plastics and non-natural textile fibers. Cellulose needs chemical modification to make these products. Until now, industry has been limited by environmental impact and cost of the process. Cellulose is also the most important biomaterial for Estonia, but industrial cellulose chemistry is limited here. At the same time, this industry gives the highest added value to cellulose. As the biorefineries, output of which is cellulose, are vigorously developing in Estonia, this project develops technology of reactive extrusion, with which cellulose can be valorized in a sustainable manner using residues from production of vegetable oils. The project strengthens cooperation between companies and academy, increases competence in the field, and contributes to academic succession.