High-Strength Liquid Crystal Polymer–Graphene Oxide Nanocomposites from Water
| Autor: | Ryan J. Fox, Maruti Hegde, Daniel P. Cole, Robert B. Moore, Stephen J. Picken, Theo J. Dingemans |
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| Rok vydání: | 2022 |
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| Zdroj: | ACS Applied Materials & Interfaces. 14:16592-16600 |
| ISSN: | 1944-8252 1944-8244 |
| DOI: | 10.1021/acsami.2c00186 |
| Popis: | We report on the morphology and mechanical properties of nanocomposite films derived from aqueous, hybrid liquid crystalline mixtures of rodlike aggregates of a sulfonated, all-aromatic polyamide, poly(2,2'-disulfonyl-4,4'-benzidine terephthalamide) (PBDT), and graphene oxide (GO) platelets. An isothermal step at 200 °C facilitates in situ partial thermal reduction of GO to reduced GO (rGO) in nanocomposite films. X-ray scattering studies reveal that PBDT-rGO nanocomposites exhibit both higher in-plane alignment of PBDT (the order parameter increases from 0.79 to 0.9 at 1.8 vol % rGO) and alignment along the casting direction (from 0.1 to 0.6 at 1.8 vol % rGO). From dynamic mechanical thermal analysis, the interaction between PBDT and rGO causes the β-relaxation activation energy for PBDT to increase with rGO concentration. Modulus mapping of nanocomposites using atomic force microscopy demonstrates enhanced local stiffness, indicating reinforcement. From stress-strain analysis, the average Young's modulus increases from 16 to 37 GPa at 1.8 vol % rGO and the average tensile strength increases from 210 to 640 MPa. Despite polymer alignment along the casting direction, an average transverse tensile strength of 230 MPa is obtained. |
| Databáze: | OpenAIRE |
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