Collar Emilia P, García-Martínez Jesús-María
Polymer Engineering Group (GIP), Polymer Science and Technology Institute (ICTP), Spanish National Research Council (CSIC), C/Juan de la Cierva, 3, 28006 Madrid, Spain.
Polymers (Basel). 2024 Sep 5;16(17):2523. doi: 10.3390/polym16172523.
This study aims to examine the 50/50 polypropylene/polyamide 6 (iPP/PA6) system molded under confined flow conditions, both in its original state and after being modified by two different interfacial agents. This study provides two main insights. Firstly, it focuses on a polymer blend close to phase inversion. Secondly, it investigates the impact of using two different types of interfacial agents (derived from polymer waste) to enhance the compatibility between iPP and PA6. Dynamic Mechanical Analysis (DMA) has been employed to achieve these objectives. It is important to note that the investigation of the 50/50 iPP/PA6 system is a crucial focus predicted in previous studies, where a series of mechanical properties were evaluated using Box-Wilson design of experiments (DOEs) over the whole compositional range on the iPP/PA6 binary system. Thus, two interfacial modifiers, namely succinic anhydride (SA)-grafted atactic polypropylene with terminal, side, and bridge SA grafts (aPP-SASA) and succinyl-fluoresceine (SF) with bridge succinic anhydride grafting atactic polypropylene (aPP-SFSA), were employed. The authors obtained and characterized these agents. The quantity of these agents used in the blend was identified as a critical coordinate in prior studies conducted by the authors. The processing method used, compression molding under confined conditions, was chosen to minimize any orientation effect on the emerging morphology. All characterization procedures were performed on samples processed by contour machining to retain the blend morphologies as they emerged from the processing stage. Results from WAXS and SAXS synchrotron tests concluded there were no changes in the crystal morphology of the iPP or the PA6 in the blends nor any co-crystallization process throughout the compositional range. These findings, and the long period fits on the PP crystalline phase for the fifty/fifty blends we are discussing, will support the present DMA study. Finally, the efficiency of these interfacial modifiers has been concluded, even in this unfavorable scenario.
本研究旨在考察在受限流动条件下模塑成型的50/50聚丙烯/聚酰胺6（iPP/PA6）体系，包括其原始状态以及经两种不同界面剂改性后的状态。本研究提供了两个主要见解。其一，聚焦于接近相转变的聚合物共混物。其二，研究使用两种不同类型的界面剂（源自聚合物废料）对增强iPP与PA6之间相容性的影响。采用动态力学分析（DMA）来实现这些目标。需要注意的是，对50/50 iPP/PA6体系的研究是先前研究中预测的关键重点，此前在iPP/PA6二元体系的整个组成范围内，使用Box-Wilson实验设计（DOEs）对一系列力学性能进行了评估。因此，使用了两种界面改性剂，即带有末端、侧链和桥接琥珀酸酐接枝（aPP-SASA）的琥珀酸酐（SA）接枝无规聚丙烯以及带有桥接琥珀酸酐接枝无规聚丙烯（aPP-SFSA）接枝的琥珀酰荧光素（SF）。作者制备并表征了这些试剂。在作者之前进行的研究中，已确定这些试剂在共混物中的用量是一个关键坐标。所采用的加工方法是在受限条件下进行压缩模塑，以尽量减少对新出现形态的任何取向影响。所有表征程序均在通过轮廓加工处理的样品上进行，以保留加工阶段出现的共混物形态。广角X射线散射（WAXS）和小角X射线散射（SAXS）同步加速器测试结果表明，共混物中iPP或PA6的晶体形态在整个组成范围内均无变化，也不存在任何共结晶过程。这些发现以及我们正在讨论的50/50共混物在PP晶相上拟合的长周期结果，将为当前DMA研究提供支持。最后，即使在这种不利情况下，也得出了这些界面改性剂的效率。
