Owing to concerns over the depletion of fossil fuels and environmental devastation, there is growing interest in reducing and replacing petroleum feedstock for the production of commodity chemicals and materials. In particular, the production of plastics from renewable resources (bioplastics) is one of the fastest-growing materials sectors in recent years. Nylons 11 and 12 are extensively used in automotive and solar industries, and these two rapidly growing markets are expected to experience an annual growth rate that exceeds 33% through 2016. In 2012, safety-related closures of petroleum-based precursor manufacturing plants led to a serious shortage of precursor material for these two markets. Consequently, auto suppliers had to actively seek other sustainable options; including new synthetic pathways from renewable feedstock or new alternative materials. Nylon 13 is a promising, yet unexploited, material that has been reported to have properties similar to that of Nylon 12.
The proposed technology enables oleic acid to be used as an economical bio-sourced feedstock for the production of Nylons 11, 12, and 13. Currently, Nylon 12 is produced from petroleum feedstock and Nylon 11 is produced from ricinoleic acid that is only available from castor beans.Over the past two years, this team has developed a new approach for the conversion of oleic acid (or oleic acid methyl ester) to Nylons 11, 12 and 13 that uses a ring-closing metathesis (RCM) step. Precursors of nylons (fatty amino acids) are currently manufactured via lengthy multi-step syntheses that produce the desired products from either a petroleum resource (Nylon 12) or from ricinoleic acid (Nylon 11) available only from castor beans. In addition, this synthetic process requires energy intensive steps involving high temperatures and pressures. In contrast, the proposed RCM method uses readily available oleic acid, and it requires fewer steps, all of which involve mild reaction conditions. Finally, the proposed approach forms fewer undesirable side-products such as isomers and oligomers (due to its mild conditions) or by-products (since all of the reagents are stoichiometric) thereby simplifying the isolation and purification of the final material.
