Influence of nanofillers and masterbatch on properties of siloxane materials

Nanocomposites based on siloxane and silicon(IV)oxide nanoparticles (with a hydrophilic and hydrophobic surface) were synthesized to design the desired final properties of the composite material. Masterbatch, a mixture of siloxane containing vinyl functional groups and reinforcing fillers, was added to improve the mechanical properties and topology of siloxane networks. Silicon(IV)oxide was added in amounts of 1, 5, 10, and 20 wt% and masterbatch in amounts of 5 and 10 wt% to examine the effect of the amounts of fillers and masterbatch in the synthesized samples. Fourier transform infrared spectroscopy was used to analyze the chemical structure of the obtained materials. Transmission electron microscopy (TEM) was used to examine the dispersion of filler particles in siloxane nanocomposites. To examine the thermal stability and phase transition temperature of siloxane materials, thermogravimetric analyzes (TGA) and differential scanning calorimetry (DSC) were performed. The addition of masterbatch did not lead to a significant difference in melting temperature, but stoichiometry was disturbed, which decreased the thermal stability compared to samples without masterbatch. The addition of masterbatch to nanocomposites with hydrophilic fillers increases both elongations at break and tensile strength. According to the results, the combination of masterbatch and nanofillers affects the properties of siloxane materials, which could enable obtaining materials with the desired properties.