Synthesis and Refined Separation of AMQ Silicone Resin for Enhanced Mechanical Property of Silicone Rubber.

Silicone resin as a common reinforcing filler of silicone rubber has attracted much attention. The traditional preparation method is greatly affected by the complicated reaction process, which leads to the difficulty of product repetition and the difference in property. In this study, nanosilica sol, a similar structure to nanosilica resulting from a hydrolysis reaction of tetraethoxysilane (TEOS), was used as a precursor to prepare a novel silicone resin (AMQ) by isolating the nucleation and growth process of resin particles. Due to the complexity of product morphology and composition, it was separated into two components (RAMQ and FAMQ) by introducing a nonsolvent to produce a precipitate from the perspective of solubility. A series of characterization methods showed that FAMQ composition had higher hydrophobicity and lower Si─OH content. Further added to silicone rubber as a filler, it also had better mechanical properties and good dispersion and compatibility. Finally, by adding 20 phr (parts per hundred of rubber) of silicone resin, the 3D printing ink exhibited the optimal shear thinning behavior and the self-supporting property. The strategy of adding nanosilica sol as nucleation seeds and separating the silicone resin provides a viable method for other types of silicone resin.