| Abstract
| - Well-defined poly(ethylene oxide)−polyacrylonitrile diblock copolymers (PEO-b-PAN) were synthesized via atom transfer radical polymerization and used as supramolecular templates for mesoporous silicas with uniform mesopores of diameter ∼ 10 nm and as precursors for mesoporous carbons with high specific surface areas (∼900 m2g-1) and large pore volumes (0.9−2.8 cm3 g-1).
- Poly(ethylene oxide)−polyacrylonitrile (PEO-b-PAN) diblock copolymers were synthesized and usedas supramolecular templates for mesoporous silicas and precursors for mesoporous carbons. The copolymerswere prepared from poly(ethylene oxide) homopolymers through chain extension with polyacrylonitrile(PAN) via atom transfer radical polymerization and had a low polydispersity index (∼1.1), a degree ofpolymerization of PAN from 16 to 208, and a PAN content of 20−70 wt %. The copolymers were usedas supramolecular templates for the formation of silica from tetraethyl orthosilicate in aqueous HCl solution.The obtained silica/PEO-b-PAN composites were calcined to obtain mesoporous silicas or heat-treatedto convert PAN into carbon, the latter being isolated through the dissolution of silica. The silicas hadspecific surface areas of ∼550 m2 g-1, total pore volumes of 0.6−1.2 cm3 g-1, and uniform mesoporesof diameter ∼10 nm, which appeared to be cylindrical with short-range ordering. The carbons had broadpore size distributions, yet some of them exhibited a certain degree of nanoscale ordering. Their surfaceareas were ∼900 m2 g-1, and the total pore volumes were 0.9−1.9 cm3 g-1. The carbons exhibited somedegree of ordering of graphene sheets in their frameworks. A clear similarity between the silica poreshape and the carbon nanostructure shape was observed for samples from the silica/EO45AN43 composite.
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