Study on the Thermal Properties and Enzymatic Degradability of Chiral Polyamide-Imides Films Based on Amino Acids

Abstract

Six kinds of chiral polyamide-imides (PAI3a⁻3f) have successfully been synthesized via direct polycondensation. The thermal properties of the materials were evaluated by the gravimetric analysis (TGA) and differential scanning calorimetry (DSC). A thermal test was conducted and showed that the polymers have good thermal stability. The Tg values were affected by the volume effect of the side groups, the internal plasticizing effect and the isolation effect. Polyamide-imides (PAIs) with L configuration showed higher Tg values than PAIs with D configuration. In the enzymatic degradation experiments of PAI films, the results showed that the structure of amino acids have the greatest influence on the degradation performance of PAIs relative to chirality. The PAI films with simple side groups and L configurations were easier to degrade. The degradation rate of natural chiral PAIs were higher than those of non-natural chiral PAIs. This makes it possible to develop polymer materials with specific degradation rates.

Keywords

• polyamide-imides (PAIs)
• degradability
• amino acids
• glass transition temperature (Tg)