Ionic Strength-Dependent Interactions and Dimensions of Adsorbed Zwitterionic Copolymers
We report direct measurements of ionic strength-dependent interactions between different molecular weights of zwitterionic triblock copolymers adsorbed to hydrophobic colloids and surfaces. The zwitterionic copolymers investigated include phosphorylcholine [poly(2-methacryloyloxyethyl phosphorylchol...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1985. - 35(2019), 14 vom: 09. Apr., Seite 4976-4985 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2019
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't |
| Zusammenfassung: | We report direct measurements of ionic strength-dependent interactions between different molecular weights of zwitterionic triblock copolymers adsorbed to hydrophobic colloids and surfaces. The zwitterionic copolymers investigated include phosphorylcholine [poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)] and sulfopropylbetaine [poly(3-( N-2-methacryloyloxyethyl- N, N-dimethyl)ammonatopropanesulfonate) (PMAPS)] end blocks separated by poly(propylene oxide) center blocks. The range of repulsion between adsorbed PMAPS copolymer layers increases with increasing NaCl from 0.01 to 3 M, and layer thicknesses range from ∼50 to 100% of the PMAPS block contour length. In contrast, repulsion between PMPC layers does not change for 0.01-3 M NaCl, and layers remain near full extension at their contour length. NaCl-dependent interactions and inferred layer dimensions correlate with hydrodynamic layer thickness and polymer second virial coefficients. These results suggest that the interaction range and layer thickness of adsorbed zwitterionic copolymers arise from a balance of intramolecular dipolar attraction and repulsion possibly mediated by water solvation. The balance between these competing effects and resulting ionic strength dependence is determined by specific zwitterionic moieties |
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| Beschreibung: | Date Completed 26.06.2020 Date Revised 26.06.2020 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.9b00218 |