Green Synthesis of Biobased Soft Foams by the Aza-Michael Reaction

The world has been facing a major resource crisis in the last few decades. In order to tackle such environmental issues, new solutions have to be found in order to replace fossil resources by more sustainable, biobased resources. One of the most promising biobased resources are vegetable oils, which are used as building blocks for renewable polymer synthesis. Industrial productions and the corresponding chemical structures make oleochemistry very attractive. Nevertheless, such building blocks have to compete with usual petrol-based monomers. Hence, this work focuses on the development of new foams in order to replace toxic foams were obtained for the first time by aza-Michael reactions, using acrylated soybean oils and biobased amines, with an original chemical blowing system. Properties of the foams have been studied in order to determine the influence of the different structures in terms of morphologies, glass transition, hardness or deformation, etc. Homogeneous open-cell foams with a pore size from 0.1 to 0.5 mm were obtained. Flexible foams were obtained with glass transition from -20 to -7 degrees C. These soft foams demonstrated a time recovery of about a few seconds and exhibited similar properties to equivalent commercial fossil-polyurethane foams, without the use of highly toxic chemicals.