Synthesis and properties of biobased copolyamides based on polyamide 10T and polyamide 56 through one-pot polymerization

A series of new biobased polyamide 10T-co-56 were synthesized with various comonomer compositions by a one-pot polycondensation reaction, and their structures and the crystalline and melting behavior were investigated using 1H NMR spectroscopy, wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC), respectively. The copolyamide exhibited a eutectic melting point at 60 mol% of 56, with melting points decreasing linearly from 310 °C to a minimum of 221 °C, and the melting enthalpies exhibited a similar tendency. WAXD was used to further characterize the crystalline and eutectic behavior of copolyamides. Moreover, the influence of the composition and comonomer sequences of copolyamides on their modulus, glass transition, thermal stability and mechanical properties were investigated.