| 1. |
- Wang, Guang, et al.
(författare)
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Controlling phase and rheological behaviours of hexagonal lyotropic liquid crystalline templates for nanostructural administration and retention
- 2022
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier. - 0021-9797 .- 1095-7103. ; 607, s. 816-825
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Tidskriftsartikel (refereegranskat)abstract
- Introducing polymerizable monomers into a binary hexagonal lyotropic liquid crystalline (LLC) template is a straightforward way for retaining the nanostructure but will decrease attractive intra-and inter aggregate interactions. It is therefore crucial to understand the interfacial interactions at nanoscale after introducing the monomers but prior to polymerization. Herein, active species, poly (ethylene glycol) diacrylate (PEGDA) and 2-hydroxyethyl methacrylate (HEMA), were introduced into hexagonal LLC of dodecyl trimethylammonium bromide and water to explore the structural variables, dimensional stabil-ity, and dynamic property. At a proper volume ratio of PEGDA/HEMA (1/4), the system presents excellent homogeneity with a higher dimensional stability and lower dynamic property from rheological assess-ments, thereby achieving robust, free-standing, and transparent membranes after photo -polymerization. The unique property of the system also lies in the much lower order-disorder transition temperature (45 degrees C) that facilitates the reorientation of mesochannels. They are in contrast inaccessible for the ternary system only with PEGDA, though the nanostructure for both systems could be retained. An insight into subtle variations in these parameters allows us to prepare a polymerizable template possess-ing higher dimensional stability and suitable flexibility via molecular design, thereby enabling simulta-neous structural alignment and retention for the development of functional nanomaterials. (c) 2021 Elsevier Inc. All rights reserved.
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| 2. |
- Wang, Guang, et al.
(författare)
-
Evolution of structural dimensions in mesoporous template precursor from hexagonal lyotropic liquid crystals
- 2020
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Ingår i: Journal of Physics. - : Institute of Physics (IOP). - 0953-8984 .- 1361-648X. ; 32:7
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Tidskriftsartikel (refereegranskat)abstract
- Producing nanopores from hexagonal lyotropic liquid crystals (LLCs) templates requires not only retaining phase morphology of the templates but also precisely controlling structural dimensions of unit cells. In this study, SAXS and H-2 NMR are used to investigate dimensional evolutions of ternary systems consisting of polymerizable species, (ethylene glycol) diacrylate (PEGDA) and/or 2-hydroxyethyl methacrylate (HEMA), in a LLCs template of hexagonally packed cylinders formed from dodecyl trimethylammonium bromide (DTAB) and water. With the addition of those polymerizable species, the system rearranges into a new hexagonal system with a smaller aggregation number, smaller pores and a thicker pore wall thickness. The hexagonal system will coexist with an aqueous-rich phase containing isotropically distributed DTAB if sufficient PEGDA is applied but the single hexagonal system could be restored by partially replacing the PEGDA with HEMA. The mobility of DTAB molecules within the aggregates varies depending on monomer compositions. The changes in structural dimensions of the unit cells and phase behaviors after adding polymerizable monomers allow dimensional control of mesochannels and potentially enable the control of selectivity and robustness of polymerized nanomaterials via molecular design.
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