Ambient Pressure Hybrid Silica Monoliths with Hexamethyldisilazane: From Vitreous Hydrophilic Xerogels to Superhydrophobic Aerogels.

ABSTRACT: Hybrid silica-based monoliths were synthesized at ambient pressure, using minimum amounts of the silylating agent hexamethyldisilazane (HMDZ). Depending on the synthesis approach, the materials ranged from dense and vitreous xerogels to transparent and superhydrophobic aerogels. Emphasis was given to understanding the role of the silylating agent, its content and incorporation process on the final morphology, and properties of the xerogels/aerogels. It is proven that as a coprecursor, increasing HMDZ content contributes to increase the lipophilic/hydrophilic balance, induce high surface areas, and decrease densities, but there is a maximum usable content for producing monoliths. Conversely, as a postsynthesis modifier, there is an optimum HMDZ content that maximizes hydrophobicity (water c

SUBMITTER: Julio MF 

PROVIDER: S-EPMC6641688 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature