In situ ultraviolet-visible spectroscopy has been used to study diffusion of two azo-dyes in a CO 2 -swollen matrix of poly(methyl methacrylate) (PMMA). The diffusivity of both dyes can be tuned simply be changing the system pressure. Higher pressure of CO 2 enhances diffusion of a dye in PMMA. The
Diffusion of disperse dyes in PET films during impregnation with a supercritical fluid
โ Scribed by S. Sicardi; L. Manna; M. Banchero
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 139 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0896-8446
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โฆ Synopsis
Studying mass transfer phenomena in polymeric films subjected to impregnation with a supercritical fluid can give interesting information for textile dyeing performances and for applications in the pharmaceutical field. The aim of this work is to propose an experimental technique to evaluate diffusion coefficients of disperse dyes in a PET film.
The 'film roll method' was used by other researchers in water impregnating systems to evaluate diffusion coefficients of non-ionic dyes in synthetic polymers. It has been extended and adapted to a supercritical impregnating system. Diffusion coefficients of two disperse dyes at different temperature (90 and 110ยฐC) and pressure values (22 and 25 MPa) have been measured and their dependence on working conditions gives a first explanation of mass transfer phenomena of disperse dyes in a PET film: experimental data can also be used to evaluate diffusion-concentration dependence.
๐ SIMILAR VOLUMES
Polyethylene (PE) fdm is used as a matrix for studying temperature-dependent equilibria by IR spectroscopy; the film is impregnated with Cp%(CO)z (Cp%$-CsMes) using supercritical CO, and subsequently saturated with HORe (RF= (CFs)zCH or (CFs)sC). At 200 K, the equilibrium between Cp\*Ir(CO)z and the