Enhancing Crystallization and Mechanical Properties of PET Polyester Using Functionalized Carbon Nanotubes

Abstract

Carbon nanotubes (CNTs) demonstrate considerable potential as crystallization-enhancing materials for polyethylene terephthalate (PET); however, their effectiveness is frequently constrained by weak interfacial bonding, which results in inefficient load transfer and premature crack propagation. To mitigate this issue, this study introduces a novel preparation method that involves the construction of hydroxyl active sites on CNTs surfaces through electrochemical processes while maintaining electrode performance. This is followed by amination modification of CNTs utilizing an APTES/ethanol system, enabling them to function as efficient nucleating agents. This innovative strategy effectively addresses the limitations of traditional stepwise processes, reducing reaction time by 90%. At a filler loading of 0.6 wt%, the prepared PET composite exhibited significant enhancements in both crystallization and mechanical properties: the tensile strength increased from 53.13 MPa to 78.8 MPa, the elongation at break reached 168%, and the crystallization half-time was reduced by 38.8%. This study presents an effective solution for leveraging functionalized carbon nanotubes as nucleating agents to improve the crystallization and mechanical properties of PET polyester.