New bio‐based epoxy materials and foams from microalgal oil

Microalgae are a potential source of renewable energy but could also interesting lead to a platform for oleochemicals. Hence, the oil obtained from Schizochytrium microalgae, with a high content in unsaturations, was dedicated to the synthesis of polymer materials. After the determination of its structure, algal oil was epoxidized in presence of exchange cation resin to reach a high functionality of ten epoxy functions per molecule. Then, fully bio-based epoxy networks were synthesized with priamine® (oleic acid dimer-derived amine) as hardener. These new algal epoxy materials were characterized and compared with vegetable oils derived epoxy networks (linseed or soybean oils). Epoxy co-monomers were added to the formulation in order to improve the material properties. We added both trimethylolpropane triglycidyl ether, a classical crosslinking agent, and triepoxided phloroglucinol, derived from algal phlorotannins. The addition epoxy co-monomers allowed to obtain materials with various properties. The thermal and mechanical properties highlighted the interesting superiority of algal oils with their high content in reactive functions. Finally, the addition of a blowing agent (MH15 polysiloxane) led to the synthesis of algal oils derived foams with interesting properties. Thus, algal oil demonstrated interesting potential as a viable starting material for fully bio-based thermosetting materials and foams. Practical applications: The main reactant described in this article, that is, epoxidized algal oil (EAO), provides bio-based aliphatic building blocks for further epoxy foams syntheses by reaction with vegetable oil derived amines and another aromatic epoxy co-monomer. The obtained epoxy materials and foams are bio-based with various rigidities and high cross-linking ratio. Materials may be used in electronics and electrical systems or for high-performance adhesives. Foams may be applied as thermal and vibration isolation and for the production of lightweight materials or the transportation industry such as aircraft-interior panels and crash pads. For the more flexible foams, medical applications could be considered.