[article]
| Titre : |
Diffusion and thermodynamic behavior of insect repellant and suntan lotion in automotive leather coatings |
| Type de document : |
texte imprimé |
| Auteurs : |
Loyd J. Burcham, Auteur ; Hans Krose, Auteur |
| Année de publication : |
2004 |
| Article en page(s) : |
p. 211-219 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Index. décimale : |
675 Technologie du cuir et de la fourrure |
| Résumé : |
The diffusion and thermodynamics of insect repellant and suntan lotion absorption into a series of polyurethane and polyacrylic resins used in leather finishing are examined. Physical testing of these resins applied as crosslinked and uncrosslinked thin-films on leather show that DEET exposure causes drastic reduction in Veslic dry rub fastness (greatly improved with a "desorption period" prior to testing). Reductions in rub fastness of samples exposed to suntan lotion were somewhat less severe than with DEET and were greatly improved by crosslinking, but severe yellowing observed during aging indicates continued degradation by non-volatile penetrants. Effective diffusion coefficients (De) and saturation weight uptake levels at equilibrium (Msat) were calculated from free-film gravimetric sorption experiments. These results indicate very high saturation levels (1000-4000 wt % for DEET absorption, ~200 wt % for suntan absorption) and even total dissolution of uncrosslinked polycaprolactone/polyester-based urethanes in DEET. Interestingly, Deep Woods OFF® (25 % DEET in an ethanol/hydrocarbon-based propellant) had identical saturation values as DEET, but with significantly higher diffusion rates - indicating diffusion promotion by highly volatile propellant solvents that do not remain absorbed in the polymer. More fundamentally, both the diffusion and saturation parameters were found to vary with the glass transition temperature, Tg, where higher Tg polymers exhibit lower diffusivity but higher equilibrium saturation levels. Calculations of sorption levels in thin-films on leather (using De values from free-film experiments) also reveal that surface wear properties degrade long before total saturation is achieved. |
| En ligne : |
https://drive.google.com/file/d/10uImOEBv5_MMX7akJ1iR8pMxQymJPJxN/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4195 |
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCIX, N° 5 (05/2004) . - p. 211-219
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Diffusion and thermodynamic behavior of insect repellant and suntan lotion in automotive leather coatings in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCIX, N° 5 (05/2004)
