Synthesis and Properties of Polyesteramides Having Short Nylon-610 Segments in the Main Chains through Polycondensation and Chain Extension

One kind of nylon-610 oligomer (PrePA) was prepared from the reaction of nylon-610 salt with sebacic acid. Polyesteramide prepolymers (PrePEAs) having amide content from 10 to 60 mol % were synthesized through melt polycondensation from adipic acid, 1,4-butanediol, and the PrePA with the catalysis of stannous chloride. Chain extension of the PrePEAs was carried out at 210 °C using 2,2′-(1,4-phenylene)-bis­(2-oxazoline) and adipoyl biscaprolactamate as combined chain extenders. The chain extended polyesteramides (ExtPEAs) with intrinsic viscosity up to 0.70 dL/g were synthesized. The ExtPEAs were characterized by FTIR and ¹H NMR spectrum, differential scanning calorimetry, wide-angle X-ray scattering, thermogravimetric analysis, tensile test, and enzymatic degradation. The results showed that the ExtPEAs were biodegradable and had T_m from 95.20 to 155.67 °C, initial decomposition temperature over 325.3 °C, and tensile strength up to 33.1 MPa.