Si and Zr based NBBS for hybrid O/I macromolecular materials starting by preformed zirconium oxo-clusters

In this study surface-functionalized zirconium oxoclusters (ZrNBB), formed by reaction between vinylacetic acid and zirconium propoxide, were chemically modified through condensation with siloxane groups, so that the core integrity of ZrNBB was preserved. The direct coupling between zirconium oxo-clusters and siloxane moiety was performed by co-polymerisation with vinyl trimethoxysilane (VTMS) with Zr:Si molar ratio 1:2 in air at room temperature and benzoyl peroxide (BPO) was used as an initiator to start radical polymerization. The polymerisation was studied by differential scanning calorimetry (DSC) and Fourier Transform Infra Red (FTIR) spectroscopy. ²⁹Si and ¹³C liquid and solid state NMR analyses were performed in order to study the microstructure of the hybrid material and the role of the clusters in polymerization and condensation. Beyond this, shear storage modulus (G′) and loss modulus (G′′), were investigated by dynamical mechanical spectroscopy (DMS). The results indicated a great stability at high temperature without any viscous flow during glass transition.