Mesoporous silica with block copolymer templates: Modulation of porosity via block copolymer reaction with silica

•PS-b-PHEA diblock copolymer was used for preparation of mesoporous silica.•This diblock copolymer was further functionalized with alkyloxysilane.•The inter-component reaction can be used to modulate the porosity of the materials.

A polystyrene-block-poly(2-hydroxyethylacrylate) diblock copolymer (PS-b-PHEA) was synthesized via a reversible addition-fragmentation chain transfer (RAFT) polymerization approach. This novel amphiphilic diblock copolymer was successfully used as the template to obtain the mesoporous silica materials. In order to modulate the porosity of mesoporous silica materials, this diblock copolymer was further functionalized via its reaction with 3-isocyanatopropyltriethoxysilane (IPTES) to afford a new diblock copolymer bearing an alkyloxysilane subchain. This derivate diblock copolymer was also employed to prepare the mesoporous silica materials through the inter-component reaction between the block copolymer and silica matrix. The results of small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) measurements showed that the inter-component reaction can be utilized to modulate the morphologies and porosity of the mesoporous silica materials.

Graphical abstractIn this work, we reported the preparation of mesoporous silica with a novel amphiphilic diblock copolymer, polystyrene-block-poly(2-hydroxylethyl acrylate) (PH-b-PHEA) as the template. In the meantime, PS-b-PHEA was further functionalized via its reaction with 3-isocyanatopropyltriethoxysilane (IPTES) to afford a derivate diblock bearing alkyloxysilane moieties, which was then used for the preparation of mesoporous silica. A comparative investigation was carried out and the effect of the inter-component reaction on the porosity was elucidated.Figure optionsDownload full-size imageDownload as PowerPoint slide