Investigation of the interface structure and filler network formation of liquid silicone rubber/silica nanocomposites based on ATR-FTIR spectroscopy and chemometrics†

Nano-silica's strong reinforcing effect on silicone rubber has led to its extensive use in composite synthesis. However, the mechanism of bound rubber formation at the interface of the two components, as well as the correlation between microstructure and mechanical properties, are poorly understood, and traditional characterization methods struggle to clarify these aspects. A chemometric method was applied to rapidly characterize silicone rubber/silica nanocomposites, and ATR-FTIR spectral analysis revealed that with increasing extraction time, the rubber component gradually decreased while the silica component remained stable and a new component emerged. Through analysis, it is hypothesized that this new component is the interfacial bonding part of the composite. This finding is significant as it deepens our understanding of the composite's structure–property relationships. It also offers a fresh approach for characterizing the interfacial bonding in silicone rubber/silica nanocomposites, potentially facilitating the development of high-performance materials.