Influence of Unsaturations on the Organization and Air Reactivity of Triglyceride Monolayers
The behavior of Langmuir monolayers of saturated and unsaturated C18 triglycerides (TAGs) was studied as two-dimensional (2D) models for paint systems at the air-water interface or transferred onto solid films. The organization of saturated tristearin (C18:0) monolayer was probed thanks to grazing i...
Publié dans: | Langmuir : the ACS journal of surfaces and colloids. - 1985. - 38(2022), 2 vom: 18. Jan., Seite 711-718 |
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Auteur principal: | |
Autres auteurs: | , , , , , , , |
Format: | Article en ligne |
Langue: | English |
Publié: |
2022
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Accès à la collection: | Langmuir : the ACS journal of surfaces and colloids |
Sujets: | Journal Article Research Support, Non-U.S. Gov't Ions Water 059QF0KO0R Triolein 122-32-7 |
Résumé: | The behavior of Langmuir monolayers of saturated and unsaturated C18 triglycerides (TAGs) was studied as two-dimensional (2D) models for paint systems at the air-water interface or transferred onto solid films. The organization of saturated tristearin (C18:0) monolayer was probed thanks to grazing incidence X-ray diffraction: one observes a hexagonal packing of the chains perpendicular to the air-water interface, in contrast to what is described in the literature. Conversely, the mono- and polyunsaturated TAGs (triolein C18:1, trilinolein C18:2, and trilinolenin C18:3) monolayers do not present any organization at the air-water interface but do exhibit peculiar reactivity regarding the air atmosphere. The obtained results derived from the evolution of surface pressure-molecular area isotherms and monolayer compressibility under different atmospheres over time, combined with ultrahigh-vacuum infrared (UHV-FTIR) spectroscopy, showed the adsorption of O2 molecules in the monolayer together with chemical reactions with hydrocarbon chains. The kinetic effect of lead ions, known to be efficient siccative agents in oil paints, was also assessed: the addition of Pb2+ in the subphase induces an increase of the O2 adsorption |
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Description: | Date Completed 01.02.2022 Date Revised 01.02.2022 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/acs.langmuir.1c02613 |