Abstract
In order to improve the performance of biodegradable materials, aliphatic- aromatic copolyesters were synthesized from sebacic acid, terephthalic acid, 1,4-butanediol and 2,5-furandicarboxylic acid via two-step esterification and poly-condensation. Copolyesters were characterized by intrinsic viscosity, gel permeation chromatography, X-ray diffraction, Fourier infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis, lipase biodegradation, tensile and cup method testing. All the copolyesters had a weight-averaged molecular weight over 61,000 g/mol or intrinsic viscosity over 1.1 dL/g when the 2,5-furandicarboxylic acid content was in the range from 2 to 10% of terephthalic acid content. Particularly, the tensile strength, yield strength, elongation at break, molecular weight and water vapor barrier of copolyesters were improved to different extents. Obviously, the addition of 2,5-furandicarboxylic acid did not significantly affect the glass transition temperature and thermal stability of polyesters. When the addition amount of 2,5-furandicarboxylic acid was 10%, the water vapor barrier of copolyester reached the highest, which was increased by 89% compared with PBAT. On the whole, the copolyesters with the addition of 6% of 2,5-furandicarboxylic acid had the best comprehensive performance, which was conducive to promoting the application of biodegradable agricultural mulching and food packaging film.
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