(588bm) Polymer-Grafted Nanoparticles for Ceramics: Thermal Treatment Effects on Dynamics, Rheology, and Char Yield

Preceramic polymer grafted nanoparticles (PCPGNPs) offer unique advantages over other preceramic materials, including increased ceramic yield, controlled particle arrangement, and reduced volume shrinkage and mass loss. This study investigates the effects of low-temperature thermal treatments on the material transformations of PCPGNPs with a silica nanoparticle core and poly(1,1-dimethylpropylsilnae) corona suspended in SMP-877. The addition of PCPGNPs to SMP-877 increased the elastic modulus and viscosity, with percolation occurring between 50-60 wt% PCPGNP. Above this concentration, the particles formed a space-spanning network. Rheological and X-ray photon correlation spectroscopy (XPCS) measurements during thermal treatments demonstrated the effect of crosslinking on the resulting moduli and dynamics. When the neat PCPGNP grafts overlapped, the moduli increased, and a jammed state persisted even when cooled to room temperature, likely contributing to increased char yield. Understanding the thermal treatment of these hybrid materials is crucial for advancing their applications in turbine engines, advanced friction, and heat-shielding components.