Samaniego-Aguilar Kerly, Sanchez-Safont Estefania, Pisa-Ripoll Ignacio, Torres-Giner Sergio, Flores Yaiza, Lagaron Jose M, Cabedo Luis, Gamez-Perez Jose
Polymers and Advanced Materials Group (PIMA), Universitat Jaume I, Av. Sos Baynat s/n, 12071 Castelló, Spain.
Institute of Food Engineering-FoodUPV, Polytechnic University of Valencia (UPV), Camino de Vera s/n, 46022 Valencia, Spain.
Polymers (Basel). 2024 Aug 16;16(16):2325. doi: 10.3390/polym16162325.
Poly(3-hydroxybutyrate--3-hydroxyvalerate) (PHBV) is a very promising biodegradable copolyester of high interest in food packaging. Its inherent brittleness and narrow processing window make it necessary to blend it with flexible biopolyesters, such as poly(butylene succinate--adipate) (PBSA). However, the resultant biopolyester blends are thermodynamically immiscible, which impairs their performance and limits their applications. This study is the first to explore the use of poly(butylene succinate--adipate) grafted with maleic anhydride (PBS--MAH) as a novel reactive additive to compatibilize PHBV/PBSA blends. The compatibilizer was prepared by a reactive melt-mixing process of PBSA and maleic anhydride (MAH) using dicumyl peroxide (DCP) as an organic radical initiator, achieving a grafting degree (G) of 5.4%. Biopolyester blend films were thereafter prepared via cast extrusion and their morphological, thermal, mechanical, and barrier properties were characterized. Compatibilization by PBSA--MAH was confirmed by observing an improved phase interaction and lower dispersed domain sizes in the blends with 15 wt% PBSA. These compatibilized PHBV/PBSA blends were thermally stable up to 285 °C, showed enhanced ductility and toughness, as well as providing an improved barrier against water and limonene vapors and oxygen. These findings suggest that the use of MAH-grafted biopolyesters can represent an effective strategy to improve the properties of biopolyester blends and open up new opportunities for the application of PHBV-based formulations for food packaging.
聚（3-羟基丁酸酯-3-羟基戊酸酯）（PHBV）是一种非常有前景的可生物降解共聚酯，在食品包装领域备受关注。其固有的脆性和狭窄的加工窗口使其有必要与柔性生物聚酯共混，如聚（丁二酸丁二醇酯-己二酸酯）（PBSA）。然而，所得的生物聚酯共混物在热力学上是不相容的，这损害了它们的性能并限制了它们的应用。本研究首次探索使用接枝马来酸酐的聚（丁二酸丁二醇酯-己二酸酯）（PBS-MAH）作为一种新型反应性添加剂来增容PHBV/PBSA共混物。通过以过氧化二苯甲酰（DCP）作为有机自由基引发剂，对PBSA和马来酸酐（MAH）进行反应性熔融共混制备增容剂，接枝率（G）达到5.4%。此后通过流延挤出制备生物聚酯共混薄膜，并对其形态、热、机械和阻隔性能进行表征。通过观察含15 wt% PBSA的共混物中相相互作用的改善和分散相域尺寸的减小，证实了PBSA-MAH的增容作用。这些增容的PHBV/PBSA共混物在高达285℃时具有热稳定性，表现出增强的延展性和韧性，同时对水、柠檬烯蒸汽和氧气提供了更好的阻隔性能。这些发现表明，使用接枝MAH的生物聚酯可以代表一种改善生物聚酯共混物性能的有效策略，并为基于PHBV的食品包装配方的应用开辟新的机会。
