Pyrrole-Containing ABA Triblock Brush Polymers as Dual Functional Molecules to Facilely Access Diverse Mesostructured Materials

Abstract

We report a new type of ABA-type brush-like triblock copolymer (PEGMA-b-PPHMA-b-PEGMA), which is characterized by two hydrophilic end segments (A) and a hydrophobic midblock (B) bearing polymerizable pyrrole moieties. This kind of symmetric triblock copolymers can not only serve as a structure-directing agent for the formation of mesoporous silicates but also function as a polymerizable monomer or carbon source for further chemical conversion to deliver mesostructured polymer or carbon materials within the preformed silicate framework. By utilizing such dual functional macromolecules, rich morphologies of mesostructures are accessible through microphase separation, and the order−order transition among cubic, lamellar, 2D hexagonal, and bicontinuous mesostructures is sensitively achievable by varying the hydrophilic volume fraction of copolymers and TEOS dosage. These features enable facile access to diverse mesostructured silica, polymer, and carbon materials. Remarkably, due to the brush-like polymer architecture and the formation of loop configuration, a widely tunable pore size from mesoscale to macroscale is realizable through using a relatively lower molecular weight copolymer. Importantly, it is found that the brush-like hydrophilic segments of our triblock copolymers can firmly anchor into the silica walls without appreciable escape of copolymer template in commonly used solvents even under reflux extraction, providing a prerequisite for reliable confined chemical transformation into mesostructured polymer and carbon materials. Our work demonstrates that the design and synthesis of functional amphiphilic block copolymers will bring great opportunity for the development of novel mesostructured materials.

Rational Fabrication of Well-Defined Mesoporous Carbon-Supported TiO2 Nanostructures for Anode Material of Lithium-Ion Batteries

“…This kind of diblock copolymer is characterized by a hydrophilic segment (PEO) and a hydrophobic block bearing polymerizable pyrrole moieties (PPHMA). Compared to the previously reported amphiphilic block copolymers, the synthesized PEO- b -PPHMA copolymers can not only serve as structure-directing agents for the formation of mesostructured materials but also function as polymerizable monomers or carbon sources for further chemical conversion to deliver mesostructured polymers or carbon materials within the preformed mesoporous frameworks. , This unique structural feature enables facile access to diverse mesoporous heterostructures.…”

“…Compared to the previously reported amphiphilic block copolymers, the synthesized PEOb-PPHMA copolymers can not only serve as structuredirecting agents for the formation of mesostructured materials but also function as polymerizable monomers or carbon sources for further chemical conversion to deliver mesostructured polymers or carbon materials within the preformed mesoporous frameworks. 28,29 This unique structural feature enables facile access to diverse mesoporous heterostructures. Figure 1 illustrates the fabrication of well-defined mesoporous carbon-supported TiO 2 heterostructures with diverse mesostructures.…”

“…In recent years, we developed two new types of block copolymers PEO- b -PPHMA and PEGMA- b -PPHMA- b -PEGMA and systematically investigated their capability of creating ordered mesostructured materials. In this work, we found that the developed polymerizable copolymers PEO- b -PPHMA possess some unique features beneficial for creating well-defined mesoporous carbon/TiO 2 heterostructure systems with high tunability.…”

Synthesis and applications of polymer cubosomes and hexosomes

“…52 After the co-assembly of BCPs and precursors (EISA and EIAA) or the infiltration of precursors into self-assembled BCP templates, crosslinking of the precursors and subsequent removal of the polymer template by calcination or solvent washing yield various networks. These networks include silica, 27,28,54,55,[57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75] silica composites, [53][54][55]76 calcite, 77 carbon, 14,56,70,71,[78][79][80][81][82][83][84][85][86][87][88] ceramic, 89 metals, [90][91][92][93]…”

“…After the co‐assembly of BCPs and precursors (EISA and EIAA) or the infiltration of precursors into self‐assembled BCP templates, crosslinking of the precursors and subsequent removal of the polymer template by calcination or solvent washing yield various networks. These networks include silica, 27,28,54,55,57–75 silica composites, 53–55,76 calcite, 77 carbon, 14,56,70,71,78–88 ceramic, 89 metals, 90–99 metal composites, 100–105 metal oxides such as aluminum oxide, 22 titania, 27,87,106–110 nickel oxide, 111 niobia, 103,112 vanadium oxide 113,114 tantalum oxide 115 and zinc oxide, 116 and polymers including PEDOT, 117 polypyrrole, 13,71,117,118 polydopamine, 13 poly‐ m ‐phenylenediamine, 13 and phenolic and epoxy resins 119…”