Toughening of Bio‐Based PA 6.19 by Copolymerization with PA 6.6 – Synthesis and Production of Melt‐Spun Monofilaments and Knitted Fabrics

Abstract

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.

Crystal Polymorphism and Phase Transition of Isodimorphic Copolyamides Based on Even–Even and Odd–Even Comonomer Units: Synergistic Effects of Copolymer Composition and Crystallization Temperature

“…Due to the high structural similarity between comonomer units, the different comonomer units of aliphatic copolyamides are usually able to cocrystallize in an isodimorphic manner. ,, In this case, the minor comonomer units can be partially included as comonomer defects in the crystalline phase formed by major comonomer units . Generally, the comonomer units with a higher content in copolymer are regarded as the major comonomer units, while the comonomer units with a lower content are designated as the minor comonomer units .…”

Water-Soluble Soft Nylons: Novel Class of Soft Matter Exhibiting LCST-type Thermo-Responsiveness

“…Polyamide research has focused primarily on improving their physical properties in bulk to produce tough fibers [5][6][7] such as aramids and polyimides. In recent years, bio-based polymers have attracted much attention due to the demand for sustainability, but polyamide research is still focused on replacing and improving toughness as fibers [8][9][10] . Consequently, the physical properties and functions in the solution of polyamides and the application of polyamides to functional soft matter research has received little attention [11][12][13][14][15] (Figure 1a).…”