Synthesis and characterization of low melting point PA6 copolyamides from ε-caprolactam with bio-based polyamide salt

Abstract

Three novel aliphatic long-chain comonomer-containing PA6 copolyamides were prepared via melt polycondensation reaction of novel bio-based N1, N6-bis(4-aminobutyl) adipamide derived polyamide salt, and ε-caprolactam. The goal of this study was to investigate the synthesis and the resulting crystal morphology, thermal, rheological and mechanical properties of copolyamides as a function of their comonomer composition. The long-chain based polyamide salt disturb the crystallization of the final copolyamides and lower the onset of melting and glass transition temperatures, which is the result of less stable γ-phase crystalline structure formation. Intriguingly, the thermogravimetric analysis measurements prove that the thermal stability of copolyamides can satisfy the requirement of multiple-processing without decomposition. Most notable is the fact that the tensile testing results exhibit outstanding mechanical behavior, i.e. elongation at break and tensile strength.