Effect of aliphatic segment length and content on crystallization and biodegradation properties of aliphatic-aromatic co-polyesters

In this work, dimethyl terephthalate (DMT), 1,4-butanediol (BDO) and different diacids were introduced to investigate the effects of variations in aliphatic chain length and component content in aliphatic aromatic terpolymers on the basic thermal properties, crystalline morphology, mechanical properties and biodegradability of the polyesters. The experimental results from nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR) and Gel permeation chromatography (GPC) indicate the successful synthesis of the anticipated aliphatic aromatic co-polyesters. The variation of melting and crystallization temperatures with aliphatic chain segment length and content were analyzed by differential scanning calorimetry (DSC). The Wide-angle X-ray diffraction (WAXD) results suggest that the coexistence of both crystals formed by rigid and flexible chain segments can be achieved by varying the length and component content of the aliphatic chain segments in the co-polyesters. The scanning electron microscopy (SEM) and composting experiment results indicate that the type of crystals formed with the more flexible chain segments and the lower degree of crystallinity have a positive effect on the biodegradability.

Automated summary

This work investigates the effects of variations in aliphatic chain length and component content in aliphatic aromatic terpolymers on the properties of the polyesters. The results indicate successful synthesis of the desired co-polyesters and the ability to achieve the coexistence of different crystals by adjusting the chain length and component content, resulting in improved biodegradability.