We report on plant oil-based linear aliphatic polyamides from 1.19-nonadecanedioic acid and aliphatic diamines of different chain lengths. Their thermal, mechanical, and rheological properties as well as the water uptake and crystalline structures were analyzed. The polyamides were synthesized with high molecular weights of 26 000 to 52 000. All polyamides showed high thermal stability with T 5% of >400 °C as well as high crystallinities of ∼50%. Injection molding of the plant-oil-based polyamides was successfully performed to produce tensile test specimens. Chemical recycling of the polyamides was demonstrated by microwave-assisted hydrolysis, with a recovery of 99% for 1.19-nonadecanedioic acid. Melt polycondensation using the recovered monomer was successfully performed to synthesize recycled polyamide in similar quality, which underlines its potential for closed loop recycling.

This work reports on the synthesis of statistical copolymers of bio‐based PA 6.19 and PA 6.6 together with the production of melt‐spun monofilaments for the production of sustainable textile fibers. The plant oil‐based 1.19‐nonadecanedioic acid is synthesized from bio‐derived oleic acid via isomerizing methoxycarbonylation. The homopolymer PA 6.19 with a carbon‐based bio‐content of 72% shows a good elongation at break of 166%, but lower tensile strength than commercial PA 6 (43 MPa versus 82 MPa). Addition of adipic acid to form statistical PA 6.6/6.19 copolymers improves toughness while maintaining the high elongation at break. Two PA 6.6/6.19 copolymers with a carbon‐based bio‐content of 26% and 33% are successfully synthesized and exhibited comparable toughness (94  ±  6 MPa and 92  ±  2 MPa) to the commercial PA 6 (92  ±  15 MPa). The bio‐based copolymers also exhibit a much lower water uptake than PA 6 and PA 6.6, resulting in a higher dimensional stability. Melt spinning of the oleic acid‐based polyamides is successfully carried out to produce monofilaments with sufficient properties for further processing in a knitting process, demonstrating the capabilities of the bio‐based PA 6.6/6.19 copolymers for use in the textile industry.