Bio-based high performance thermosets: Stabilization and reinforcement of eugenol-based benzoxazine networks with BMI and CNT

This work presents the solventless synthesis, the reinforcement and the thermal stabilization of bio-based bis-benzoxazine resins derived from eugenol. The structure of this benzoxazine monomer was confirmed by H-1 NMR. The polymerization and degradation of the precursor have been investigated and monitored by DSC and TGA and showed a limited crosslinking ability due to the steric hindrance of the eugenol based aromatic ring. A bis-maleimide (bMI) has been used to stabilize the benzoxazine moiety while it undergoes also a copolymerization through an ene-addition. Depending on its relative content, the bis-maleimide proved to limit the thermal degradation of the bis-benzoxazine monomer and allowed the formation of a dense crosslinked network with high thermomechanical stability. Furthermore, the properties of the network were significantly improved by the incorporation of a small amount of carbon nanotubes (CNTs) with an increase of the T-g as high as 60 degrees C. The combination of bMI and CNTs will allow the use of this new bio-based benzoxazine resin as matrices for the preparation of sustainable high performance biocomposite materials. (C) 2014 Elsevier Ltd. All rights reserved.