Impact of the functionalized clay nanofillers on the properties of the recycled polyethylene terephthalate nanocomposites

Abstract

AbstractPolymer nanocomposites, such as polyethylene terephthalate (PET)‐clay systems, leverage intricate interactions between components to fine‐tune their thermal, mechanical, and rheological properties. In our study, we functionalized montmorillonite clay nanofillers (CloisiteNa+) to fabricate recycled PET‐clay nanocomposites. The nanofillers underwent a three‐step functionalization process, involving the treatment with (3‐Aminopropyl)triethoxysilane (APTES), the grafting of initiating coatings (multifunctional peroxide initiator, [MPI]) onto clay/APTES, and the subsequent fabrication of grafted brushes using poly(butyl methacrylate) (PBMA) or poly(butyl acrylate) (PBA). The functionalization process and the properties of the modified clay were successfully confirmed through Fourier‐transform infrared spectroscopy and thermogravimetric analysis. The fabrication of nanocomposites, incorporating both clay and functionalized clay, influenced the thermal behavior of the composites, whereas the nanofillers had no discernible impact on the flow temperature. The PET and nanocomposites exhibited liquid viscoelastic behavior, with the exception of PET with clay, which displayed shear‐thinning and “rubber‐like” behavior. Rheological curves and x‐ray diffraction (XRD) analysis indicated improved dispersion and compatibility for clay/APTES and clay functionalized with PBA‐grafted brushes within the PET matrix. In some instances, the utilization of functionalized clay resulted in enhanced compatibility and customized properties in PET‐organoclay nanocomposites compared with conventional fillers. These findings bear implications for a broad spectrum of applications involving PET‐organoclay nanocomposites.