| Autor: |
Shah, Neel J, Dadashi-Silab, Sajjad, Galluzzo, Michael D, Chakraborty, Saheli, Loo, Whitney S, Matyjaszewski, Krzysztof, Balsara, Nitash P |
| Rok vydání: |
2021 |
| Předmět: |
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| Zdroj: |
Macromolecules, vol 54, iss 3 |
| Popis: |
We studied the effect of salt addition on a diblock copolymer system with a negative Flory-Huggins interaction parameter, χ, indicative of attractive interactions between the two blocks. The system studied is poly(ethylene oxide)-block-poly(methyl methacrylate) (PEO-PMMA) with added lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. We studied two asymmetric block copolymers, PEO-PMMA(10-33) and PEO-PMMA(10-64), where the numbers refer to the molar masses of the blocks in kg mol-1. The small-angle X-ray scattering (SAXS) profiles for PEO-PMMA(10-33) were featureless at all salt concentrations. In contrast, PEO-PMMA(10-64) exhibited SAXS peaks when the salt concentration was between 0.22 ≤ m (mol Li/kg polymer) ≤ 0.44. The appearance of SAXS peaks only in PEO-PMMA(10-64) is consistent with the predictions of ionic self-consistent field theory developed by de la Cruz and co-workers, which predicts that in systems with negative χ, ordered phases are only found when the volume fraction of the ionic block is about 10%. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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