Magazzini Luca, Grilli Sara, Fenni Seif Eddine, Donetti Alessandro, Cavallo Dario, Monticelli Orietta
Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, Via Dodecaneso 31, 16146 Genova, Italy.
Natur-World S.p.A., Via Roma 8/2, 16121 Genova, Italy.
Polymers (Basel). 2021 Aug 18;13(16):2780. doi: 10.3390/polym13162780.
Poly(glycolic acid) (PGA) holds unique properties, including high gas barrier properties, high tensile strength, high resistance to common organic solvents, high heat distortion temperature, high stiffness, as well as fast biodegradability and compostability. Nevertheless, this polymer has not been exploited at a large scale due to its relatively high production cost. As such, the combination of PGA with other bioplastics on one hand could reduce the material final cost and on the other disclose new properties while maintaining its "green" features. With this in mind, in this work, PGA was combined with two of the most widely applied bioplastics, namely poly(l-lactide) (PLLA) and poycaprolactone (PCL), using the melt blending technique, which is an easily scalable method. FE-SEM measurements demonstrated the formation of PGA domains whose dimensions depended on the polymer matrix and which turned out to decrease by diminishing the PGA content in the mixture. Although there was scarce compatibility between the blend components, interestingly, PGA was found to affect both the thermal properties and the degradation behavior of the polymer matrices. In particular, concerning the latter property, the presence of PGA in the blends turned out to accelerate the hydrolysis process, particularly in the case of the PLLA-based systems.
聚乙醇酸(PGA)具有独特的性能,包括高气体阻隔性能、高拉伸强度、对常见有机溶剂的高耐受性、高热变形温度、高硬度,以及快速的生物降解性和可堆肥性。然而,由于其相对较高的生产成本,这种聚合物尚未得到大规模开发。因此,一方面将PGA与其他生物塑料结合可以降低材料的最终成本,另一方面在保持其“绿色”特性的同时揭示新的性能。考虑到这一点,在这项工作中,采用易于扩展的熔融共混技术,将PGA与两种应用最广泛的生物塑料,即聚(L-丙交酯)(PLLA)和聚己内酯(PCL)进行了结合。场发射扫描电子显微镜(FE-SEM)测量表明形成了PGA域,其尺寸取决于聚合物基体,并且随着混合物中PGA含量的减少而减小。尽管共混组分之间的相容性很差,但有趣的是,发现PGA会影响聚合物基体的热性能和降解行为。特别是关于后一种性能,共混物中PGA的存在被证明会加速水解过程,尤其是在基于PLLA的体系中。