Effect of MXene as nucleating agent on crystallization behaviour and thermal stability of PET nanocomposites

Abstract MXene (Ti 3 C 2 T x ) nanosheets were synthesised by selective etching of the Ti 3 AlC 2 MAX phase and subsequently incorporated into polyethylene terephthalate (PET) via solution blending to afford PET/MXene nanocomposites. Owing to their high specific surface area and abundant surface terminations, MXene sheets acted as efficient heterogeneous nucleation sites within the PET matrix. Consequently, the crystallisation peak temperature ( T c ) of the nanocomposite containing 1 wt % MXene (PET-MX-1) rose from 186.4 °C to 212.6 °C and the overall crystallisation rate was markedly accelerated with respect to neat PET. Non-isothermal kinetic analysis confirmed that MXene lowered the apparent crystallisation activation energy and thus enhanced crystallisation kinetics, while thermogravimetric measurements revealed a modest improvement in thermal stability. These findings demonstrate that the introduction of trace amounts of MXene offers a simple yet effective strategy for tailoring the crystallisation behaviour and thermal performance of PET, thereby expanding its potential for high-performance engineering applications.