Novel compatibilized nylon-based ternary blends with polypropylene and poly(lactic acid): morphology evolution and...

Area of Science:

• Polymer Science and Engineering
• Materials Science
• Composite Materials

Background:

• Nylon 6 (PA6), polypropylene (PP), and poly(lactic acid) (PLA) are immiscible polymers, posing challenges for blend development.
• Improving interfacial adhesion and phase dispersion is crucial for creating high-performance polymer blends.
• Reactive compatibilization offers a promising route to enhance miscibility in polymer systems.

Purpose of the Study:

• To investigate the reactive compatibilization of PA6/PP/PLA ternary blends using maleic anhydride grafted polypropylene (PP-g-MA).
• To characterize the morphology, interfacial interactions, and rheological behavior of the developed polymer blends.
• To elucidate the influence of PP-g-MA on phase dispersion and polymer-polymer affinity.

Main Methods:

• Melt extrusion of binary and ternary polymer blends at various compositions.
• Morphological analysis using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).
• Surface and interfacial tension measurements.
• Rheological measurements to determine viscosity ratios and investigate phase interactions.

Main Results:

• PP-g-MA significantly improved compatibility, leading to a drastic reduction in PP dispersed phase particle size.
• Stronger affinity was observed between PA6 and PLA compared to PLA and PP, explaining PLA phase dispersion.
• Rheological measurements confirmed high PA6-PLA interaction and provided insights into phase separation mechanisms.

Conclusions:

• Reactive extrusion with PP-g-MA is an effective strategy for compatibilizing PA6/PP/PLA blends.
• The study highlights the critical role of interfacial interactions and viscosity ratios in determining blend morphology.
• Morphological development is strongly influenced by droplet size and chain relaxation dynamics in the melt.