PDF(Pubmed)
Abstract：
To obtain more sustainable and active food packaging materials, PHBV films containing 5% wt. of phenolic compounds with different molecular structures (ferulic acid, vanillin, and catechin) and proved antioxidant and antimicrobial properties were obtained by melt blending and compression molding. These were characterized by their structural, mechanical, barrier, and optical properties, as well as the polymer crystallization, thermal stability, and component migration in different food simulants. Phenolic compounds were homogenously integrated within the polymer matrix, affecting the film properties differently. Ferulic acid, and mainly catechin, had an anti-plasticizing effect (increasing the polymer glass transition temperature), decreasing the film extensibility and the resistance to breaking, with slight changes in the elastic modulus. In contrast, vanillin provoked a plasticizing effect, decreasing the elastic modulus without notable changes in the film extensibility while increasing the water vapor permeability. All phenolic compounds, mainly catechin, improved the oxygen barrier capacity of PHBV films and interfered with the polymer crystallization, reducing the melting point and crystallinity degree. The thermal stability of the material was little affected by the incorporation of phenols. The migration of passive components of the different PHBV films was lower than the overall migration limit in every simulant. Phenolic compounds were released to a different extent depending on their thermo-sensitivity, which affected their final content in the film, their bonding forces in the polymer matrix, and the simulant polarity. Their effective release in real foods will determine their active action for food preservation. Catechin was the best preserved, while ferulic acid was the most released.
摘要：
为了获得更可持续和活性的食品包装材料，PHBV薄膜含有5%wt。具有不同分子结构的酚类化合物(阿魏酸，香兰素,和儿茶素），并通过熔融共混和压缩成型获得了证明的抗氧化和抗菌性能。这些以它们的结构为特征，机械,屏障,和光学性质，以及聚合物结晶，热稳定性，和不同食物模拟物中的成分迁移。酚类化合物均匀地整合在聚合物基质中，对薄膜性能的影响不同。阿魏酸,主要是儿茶素，具有抗增塑作用（提高聚合物的玻璃化转变温度），降低薄膜的延伸性和抗断裂性，弹性模量略有变化。相比之下,香草醛引起了增塑效果，降低弹性模量，膜的延展性没有显著变化，同时增加水蒸气渗透性。所有酚类化合物,主要是儿茶素,提高了PHBV薄膜的氧阻隔能力，干扰了聚合物的结晶，降低熔点和结晶度。酚类的掺入对材料的热稳定性影响很小。不同PHBV膜的无源元件的迁移低于每种模拟物中的总迁移极限。酚类化合物的释放程度不同，取决于它们的热敏感性，这影响了他们在电影中的最终内容，它们在聚合物基质中的结合力，和模拟极性。它们在真实食物中的有效释放将决定它们对食物保存的积极作用。儿茶素是保存最好的,而阿魏酸释放最多。
