A Family of Highly Ordered Mesoporous Polymer Resin and Carbon Structures from Organic−Organic Self-Assembly

Abstract

The syntheses of a family of highly ordered mesoporous polymers and carbon frameworks from organic−organic assembly of triblock copolymers with soluble, low-molecular-weight phenolic resin precursors (resols) by an evaporation induced self-assembly strategy have been reported in detail. The family members include two-dimensional hexagonal (space group, p6m), three-dimensional bicontinuous (Ia3̄d), body-centered cubic (Im3̄m), and lamellar mesostructures, which are controlled by simply adjusting the ratio of phenol/template or poly(ethylene oxide)/poly(propylene oxide) in the templates. A five-step mechanism from organic−organic assembly has been demonstrated. Cubic FDU-14 with a gyroidal mesostructure of polymer resin or carbon has been synthesized for the first time by using the copolymer Pluronic P123 as a template in a relatively narrow range. Upon calcination at 350 °C, the templates should be removed to obtain mesoporous polymers, and further heating at above a critical temperature of 600 °C transforms the mesoporous polymers to the homologous carbon frameworks. The mesoporous polymer resin and carbon product materials exhibit ordered structures, high surface areas, (670−1490 m2/g), large pore volumes (0.65−0.85 cm3/g), and uniform, large pore sizes (7.0−3.9 nm), as well as very thick pore walls (6−8 nm). The carbon open frameworks with covalently bonded constructions and thick pore walls exhibit high thermal stability (>1400 °C). Our results show that the feed gas used during the calcination has a great influence on the porosity of the products. The presence of a small amount of oxygen facilitates the large pore sizes and high surface areas of mesoporous materials with different mesostructures. An extraction method employing sulfuric acid can also decompose the template from hexagonal mesostructured polymers with little framework shrinkage. Preliminary studies of the mechanical and electrochemical properties of mesoporous carbon molecular sieves are also presented.

A Hierarchically Porous Carbon Fabric for Highly Sensitive Electrochemical Sensors

“…[37] The pore distribution and specific surface area of the HC-PET were investigated from the nitrogen sorption isotherms, as shown in Figure 2a. The N 2 adsorption-desorption isotherm of the HC-PET was a type-IV curve, according to IUPAC classification, [38] with an H 2 -type hysteresis loop, similar to previously reported meso-porous materials, [36] indicating uniform cylindrical pores. The pore size distributions derived from the adsorption branches by using the BJH model [39] indicated a pore size of 3.4 nm, and a BET surface area of 407 m 2 g À1 .…”

“…[36] Typically, 6.1 g of phenol was melted in a three-neck flask at 40-42 C. 1.3 g of 20 wt% NaOH aqueous solution was stirred in. After 10 min, 10.5 g of formalin solution was carefully added dropwise over 10 min.…”

“…As the F127 was decomposed during pyrolysis, it resulted in meso-porous materials with pore sizes ranging from 2 [36] to 32 nm. [37] The pore distribution and specific surface area of the HC-PET were investigated from the nitrogen sorption isotherms, as shown in Figure 2a.…”

Structurally Designed Synthesis of Mechanically Stable Poly(benzoxazine-co-resol)-Based Porous Carbon Monoliths and Their Application as High-Performance CO2 Capture Sorbents

“…The signals at ∼72 and 17 ppm correspond to the carbons in the methylene and methyl groups of the block copolymer F127 template. 52,59 These results demonstrate that the as-made poly(benzoxazine-coresol) polymer monoliths show hybrid characteristics consisting of poly(RF), polybenzoxazine (RF-DAH) segments, and a block copolymer.…”

Monolithic porous carbon materials prepared from polyurethane foam templates

“…The base procedure was adapted from the literature [10] and involved the previous preparation of a resol precursor from phenol and formaldehyde. During the optimization procedure it was verified that the resol precursor should not be aged, because the best results were obtained with freshly prepared resol solutions.…”