*3.5. Dynamic Mechanical Analysis*

The storage modulus as a function of temperature for PBAT/Ti3C2TX nanocomposite casting films is shown in Figure 5a. It is clear that the storage modulus of the PBAT nanocomposite reinforced with Ti3C2TX was higher than that of PBAT-0 in the glassy states. In addition, the reinforcement effect was more obvious with the increase of Ti3C2TX content. When compared to PBAT-0, the storage modulus of PBAT-2.0 at 80 ◦C increased from 1220 MPa to 2342 MPa. This is due to the stiffening effect of rigid Ti3C2TX nanosheets. Aside from this, the polar groups on the surface of Ti3C2TX may have had intramolecular interaction with the PBAT. matrix, which may have also improved the storage modulus of the PBAT/Ti3C2TX nanocomposites [43]. The loss factor peak (tan*δ*) is usually defined as the glass transition temperature (*T*g). It is observable from Figure 5b that the *T*<sup>g</sup> shifted to a lower temperature when the PBAT matrix was incorporated with Ti3C2TX. With the addition of 2 wt% Ti3C2TX, the PBAT-2.0 shifted from −11.9 ◦C to −15.0 ◦C, as compared with that of PBAT-0. It can be attributed to the incorporation of Ti3C2TX, which can improve the chain mobility of the amorphous regions of PBAT due to the liberation effect of Ti3C2TX. In addition, the height of tan*δ* also showed a slight increase, indicating that an increase in Ti3C2TX content will result in higher dissipative energy [45].

**Figure 5.** (**a**) Storage modulus and (**b**) loss factor of PBAT/Ti3C2TX nanocomposite casting films.
