Synthesis of p6mm hexagonal mesoporous carbons and silicas using Pluronic F127–PF resin polymer blends

A miscible polymer blend of Pluronic F127 and phenol–formaldehyde (PF) resin through the interaction of multiple hydrogen bonds was used as a new template to synthesize a well-ordered p6mm mesostructured PF resin–F127–silica composite. By using that dual-function composite, the mesoporous silica was obtained from calcination, and mesoporous carbon was generated after carbonization and HF-etching. Both the mesoporous silica and carbons have the same morphology of hierarchical micro-fibers and the well-ordered p6mm hexagonal mesostructures. Because of the hydrophobicity of the PF resin, blending with the PF resin can induce a mesophase transformation in the PF resin–F127–silica composite. At PF resin/F127 weight ratio of 0.75, a transformation from Im3m 3D-cubic to p6mm 2D-hexagonal mesostructure occurred. In addition to F127, other block copolymers can also blend well with PF resin and these polymer blends were utilized as well, and these polymer blends were utilized to produce the mesoporous carbons and silicas of different pore sizes. In practice, this polymer blending method can provide an efficient way to synthesize the mesoporous silicas and carbons by the non-volatile and inexpensive polymers.