title: ABC copolymer silicone surfactant templating for biomimetic silicification.
abstract: Using the ABC copolymer silicone surfactant polydimethylsiloxane (PDMS)-graft-(polyethylene oxide (PEO)-block-propylene oxide (PPO)) (PSEP, Scheme 1a) as a template and tetraethoxysilane (TEOS) as a silica source, silica particles with various structures and morphologies (i.e., disordered spherical micellar aggregation, two-dimensional p6mm mesostructure, asymmetric multi-layer non-equilibrium vesicles and symmetric monolayer vesicles) were synthesized by changing the synthesis temperature from 30 to 80 °C. Increasing the hydrophobicity of the surfactant by increasing the temperature resulted in an increase in the surfactant packing parameter g, which led to the mesophase transformation from micellar to cylinder and later to a lamellar structure. The good compatibility between the PDMS and the TEOS, the different natures of the hydrophobic PDMS and PPO segments, and the hydrolysis and condensation rates of TEOS enabled the variation of silicification structures. This novel silicone surfactant templating route and a new type of materials with highly ordered mesostructures and asymmetric morphologies provide a new insight into the molecular factors governing inorganic-organic mesophase and biosilicification for fabricating functionalized materials.
authors.affiliation: School of Chemistry and Chemical Technology, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.forename: Caiyun
authors.initials: C
authors.lastname: Guo
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yao
authors.forename: Shunai
authors.initials: S
authors.lastname: Che
mesh_terms: D040761:Biomimetic Materials / Q000138:chemical synthesis* / Q000737:chemistry; D004129:Dimethylpolysiloxanes / Q000138:chemical synthesis* / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D009757:Nylons / Q000138:chemical synthesis* / Q000737:chemistry; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D011409:Propylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry; D012821:Silanes / Q000737:chemistry*; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry; D013501:Surface-Active Agents / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D004129:Dimethylpolysiloxanes; D009757:Nylons; D011108:Polymers; D011409:Propylene Glycols; D012821:Silanes; D013501:Surface-Active Agents; C085707:poly(dimethylsiloxane)-polyamide copolymer; C012504:polypropylene glycol; D011092:Polyethylene Glycols; C040733:tetraethoxysilane; D012822:Silicon Dioxide