The conversion of woody oils into E-octadec-9-enedioic acid and multiple-shape memory polyamides

Although tremendous efforts have been made to convert woody oils into valuable chemicals, most of the known protocols still require multi-step procedures and rigorous conditions. Herein, a highly efficient method for converting woody oils into long-chain unsaturated dicarboxylic acid was reported. Such a strategy holds promises for opening new routes for utilizing woody oils. Firstly, self-metathesis of fatty acids from Rubber seed oil (RSO), Sapium sebiferum oil (SSO) and High oleic Canola oil (HOCO) were optimized. Pure E-octadec-9-enedioic acid monomer (C18) was obtained, and confirmed by 1H NMR and FTIR spectra. The prepared dicarboxylic acid was then experienced condensation polymerization with 1,6-hexamethylenediamine. The chemical structures of the obtained polyamides were investigated by FTIR and 13C NMR spectra. DSC, TGA, DMA, and tensile testing was used to explored their thermal and mechanical properties. Interestingly, due to the existence of broad melting and glass transition, the prepared polyamides possess multiple-shape memory properties.