Studies of inherent mixing and physical properties for green polymer blends comprising natural polyphenol and biodegradable polymer with aliphatic-aromatic backbone

Abstract

The functional blends of green materials are of great interest. In this study, we discovered a rare case of inherent miscibility in blends comprising a biodegradable polymer, poly(butylene adipate-co-butylene terephthalate) [P(BA-co-BT)], and a biocompatible natural polyphenol, catechin. According to the homogeneous phase morphology and single composition-dependent Tg (obtained from the microscopy and thermal analysis measurements), this work demonstrated that a natural polyphenol could be intimately mixed with a biodegradable copolyester showing a special aliphatic-aromatic backbone. The results of IR spectra and equilibrium melting point depression further indicated that it existed intermolecular interactions in the blends. We suggest that the molecular mixing between catechin and P(BA-co-BT) should be attributed to the preferable interactions of hydrogen bonding. Physical properties were also discussed in detail with studying the crystallization property of the blends. The nonisothermal crystallization of P(BA-co-BT) was also found to be influenced by the catechin in the blends. By the analysis results of the Mo model, it demonstrated that the rate dependent parameter, F(T), was increased as the catechin content was increased in the blends. In indicated that the rate of nonisothermal crystallization of P(BA-co-BT) was decreased with the addition of catechin in the blends.