Sequential Structure Regulation Toward Bio‐Based Polyamide 512 Elastomers: Wide Hardness Range and Adjustable Mechanical Properties

Bio‐based thermoplastic polyamide elastomers (TPAEs) are gaining increasing attention with significant applications. Herein, a series of semi‐bio‐based polyamide elastomers with different sequential structures were successfully synthesized via a two‐step melt polymerization process using bio‐based short‐chain liquid monomers as starting materials. The resulting TPAEs consist of a hard segment, polyamide 512, and a soft segment, poly (tetramethylene glycol) (PTMG), exhibiting excellent comprehensive properties through sequential structure regulation by adjusting the ratio of hard and soft segments. Specifically, the TPAEs exhibit molecular weights ranging from 16 000 to 19 000 g·mol −1 and hardness adjustable between 20 and 50 D, making it suitable for various application scenarios. Moreover, the prepared TPAEs demonstrate a wide processing range and good thermal stability with a melting point exceeding 190°C and a thermal decomposition temperature above 350°C, as well as elongation at break exceeding 500%. This study presents an environmentally friendly and efficient method for synthesizing elastomeric materials by utilizing short‐chain bio‐based monomers.