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Abstract Cadmium sulfide (CdS) pigments have degraded in several well-known artworks, but the influence of pigment properties and environmental conditions on the degradation process have yet to be fully understood. Traditional non-destructive analysis techniques primarily focus on macroscopic degradation, whereas microscopic information is typically obtained with invasive techniques that require sample removal. Here, we demonstrate the use of pump-probe microscopy to nondestructively visualize the three-dimensional structure and degradation progress of CdS pigments in oil paints. CdS pigments, reproduced following historical synthesis methods, were reproduced as oil paints and artificially aged by exposure to high relative humidity and light. The degradation of CdS to CdSO4·xH2O was confirmed by both FTIR (Fourier-transform infrared) and XPS (x-ray photoelectron spectroscopy) experiments. During the degradation process, optical pump-probe microscopy was applied to track the degradation progress in single grains, and volumetric imaging revealed early CdS degradation of small particles and on the surface of large particles. This indicates that the particle dimension influences the extent and evolution of degradation of historical CdS. In addition, the pump-probe signal decrease in degraded CdS is observable before visible changes to the eye, demonstrating that pump-probe microscopy is a promising tool to detect early-stage degradation in artworks.
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Solvent-induced competing processes in polycarbonate degradation: depolymerization, chain scission, and branching/crosslinking
Catalyzed by copper sulfide nanoparticles (CuS NPs), polycarbonate (PC) degradation exhibits different degradation behaviors in varying solvents, showing competitive processes of chain scission, branching, and crosslinking.
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- Award ID(s):
- 1752611
- PAR ID:
- 10499305
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 14
- Issue:
- 16
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 1915 to 1922
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2py01572b
