Impact of cellulose nanocrystals reinforcement on molecular dynamics and dielectric properties of PCL ‐based polyurethane

The thermal and dielectric properties of polymer nanocomposites based on polycaprolactone diol-based PU matrix filled with various weight fractions of cellulose nanocrystals (CNCs) (from 0 to 10 wt%) extracted from the rachis of date palm tree were investigated by differential scanning calorimetry (DSC) and broadband dielectric spectroscopy. The emphasis was on clarifying the impact of the addition of CNC nanofillers on the molecular mobility of the PU matrix. Different dielectric relaxations have been found and the corresponding activation energies have been calculated, by means of the Havriliak–Negami model after fitting the dielectric data. The outcomes were explored in terms of molecular dynamics and interfacial processes. With 2.5 wt% of CNC, the strongest adhesion between matrix and reinforcement was acquired. This research was supported by the use of DSC for thermal properties.