Pietrosanto Arianna, Scarfato Paola, Di Maio Luciano, Incarnato Loredana
Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy.
Materials (Basel). 2020 Nov 27;13(23):5395. doi: 10.3390/ma13235395.
In this work, eco-sustainable blown films with improved performance, suitable for flexible packaging applications requiring high ductility, were developed and characterized. Films were made by blending two bioplastics with complementary properties-the ductile and flexible poly(butylene-adipate--terephthalate) (PBAT) and the rigid and brittle poly(lactic acid) (PLA)-at a 60/40 mass ratio. With the aim of improving the blends' performance, the effects of two types of PLA, differing for viscosity and stereoregularity, and the addition of a commercial polymer chain extender (Joncryl), were analyzed. The use of the PLA with a viscosity ratio closer to PBAT and lower stereoregularity led to a finer morphology and better interfacial adhesion between the phases, and the addition of the chain extender further reduced the size of the dispersed phase domains, with beneficial effects on the mechanical response of the produced films. The best system composition, made by the blend of PBAT, amorphous PLA, and the compatibilizer, proved to have improved mechanical properties, with a good balance between stiffness and ductility and also good transparency and sealability, which are desirable features for flexible packaging applications.
在这项工作中，开发并表征了具有改进性能的生态可持续吹塑薄膜，其适用于需要高延展性的软包装应用。薄膜通过将两种具有互补性能的生物塑料——韧性且柔性的聚（丁二酸丁二醇酯-对苯二甲酸丁二醇酯）（PBAT）和刚性且脆性的聚乳酸（PLA）——以60/40的质量比共混制成。为了提高共混物的性能，分析了两种粘度和立构规整度不同的PLA以及添加一种商业聚合物扩链剂（Joncryl）的效果。使用粘度比更接近PBAT且立构规整度更低的PLA导致了更精细的形态以及各相之间更好的界面粘附，并且添加扩链剂进一步减小了分散相畴的尺寸，对所制备薄膜的力学响应产生了有益影响。由PBAT、无定形PLA和增容剂共混制成的最佳体系组成被证明具有改进的力学性能，在刚度和延展性之间具有良好的平衡，并且还具有良好的透明度和密封性，这些都是软包装应用所需的特性。
