Synergistic enhancement effect of multi-dimensional nanomaterials on high-damping polyurethane

Nanomaterials are increasingly used to improve the mechanical or damping properties of polymers due to their high specific surface area, surface activity and exotic physicochemical properties. There may be a disadvantage to using only one type of nanofiller, as evidenced by an increase in certain properties and a decrease in others. To improve the damping and mechanical properties simultaneously, a promising method has been proposed to use nanofillers with many different dimensions. However, their synergistic enhancement is still little explored. In this study, four nanofillers of different dimensions, namely AO-2246 (0D), carbon nanotubes (CNTs, 1D), sericite (2D), and tetra-needle-like ZnO whiskers (T-ZnOw, 3D), were selected to enhance the properties of millable polyurethane (MPU) matrix. The synergistic enhancement effect was evaluated by analysing the static and dynamic mechanical properties of the composites. Orthogonal test results were used to understand the importance of the four nanofillers and the interactions among them. A multi-index evaluation method based on Analytic Hierarchy Process (AHP) was established to obtain the optimal gradation of the four fillers to maximise their synergistic enhancement effect. The results showed that the gradation of the different nanofillers was an important factor that had a significant effect on the synergistic enhancement. The optimised polyurethane showed improvements in peak loss factor (η_max) of 25.18%, effective damping temperature range (ΔT_0.3) of 24.02%, and glass transition temperature (T_g) of 180.39%.