摘要
Silica aerogels (SAs) impart low density and excellent thermal insulation to polymer systems, yet incorporating hydrophobic SAs into aqueous rubber latex systems remains challenging owing to their poor dispersibility and potential to destabilize the latex. Although previous studies have dispersed SAs in aqueous poly(vinyl alcohol) (PVA), the stability of such dispersions and their effectiveness as bridging media for latex integration have not been thoroughly evaluated, which limits their practical application in latex compounding. This study systematically examined how the surface chemistry governs hydrolytic stability, interfacial behavior, and latex compatibility in PVA-assisted aqueous processing. Two hydrophobic SAs were prepared: ethoxy-modified SA (E-SA) and methyl-modified SA (M-SA). Both initially formed a homogeneous PVA slurry, but E-SA rapidly hydrolyzed its surface —OCH 2 CH 3 groups, releasing ethanol, becoming hydrophilic, and undergoing irreversible nanopore collapse. In contrast, M-SA maintains its structural integrity and hydrophobicity because its —Si(CH 3 ) 3 groups are highly resistant to hydrolysis. This divergence dictates the behavior during latex blending. The ethanol released from E-SA disrupts electrostatic and steric stabilization, inducing latex coagulation, whereas M-SA/PVA dispersions preserve colloidal stability across diverse latex systems. As a practical demonstration, M-SA-reinforced chlorosulfonated polyethylene (CSM) rubber latex composites show more than a 50% reduction in thermal conductivity while maintaining chemical resistance, enabling high-performance insulating protective gloves and coatings. This work establishes a critical link between aerogel surface chemistry and aqueous processing stability, providing a mechanistic foundation for the rational design of water-based rubber/silica aerogel composites and next-generation thermal insulation materials.
危险品化学品经营许可证（带存储）