Titre : |
The water vapour permeability of leather finished by thermally responsive polyurethane |
Type de document : |
texte imprimé |
Auteurs : |
Haojun Fan, Auteur ; Ling Li, Auteur ; Xinnian Fan, Auteur ; Bi Shi, Auteur |
Année de publication : |
2005 |
Article en page(s) : |
p. 121-125 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Analyse thermomécanique dynamique Butanediol Caractérisation Cuirs et peaux -- Finition Diisocyanate d'isophorone Gonflement (physique) Matériaux thermosensibles Mesure Perméabilité Poly-e-caprolactone Polymères en émulsion Polyuréthanes Propionique diméthylol, Acide Revêtements organiques Transition de phaseEn physique, une transition de phase est une transformation du système étudié provoquée par la variation d'un paramètre extérieur particulier (température, champ magnétique...).
Cette transition a lieu lorsque le paramètre atteint une valeur seuil (plancher ou plafond selon le sens de variation). La transformation est un changement des propriétés du système. Vapeur d'eau
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Index. décimale : |
675 Technologie du cuir et de la fourrure |
Résumé : |
A water-based thermally-responsive polyurethane (TRPU), based on the crystalline soft segment from the reaction of polycaprolactone diol (PCL) with isophorone diisocyanate (IPDI) and the crystalline hard segment from the reaction of IPDI -1,4-butanediol (BDO) together with dimethylolpropionic acid (DMPA), was synthesized and used in water vapour permeable leather finishing.
Differential Scanning Calorimetry (DSC), Dynamic Mechanical Thermal Analyzer (DMTA), water swelling and water vapour permeability (WVP) were measured to evaluate how the structure of PU and the temperature influence the WVP of PU films and finished leathers.
In contrast to common polyurethane elastomer (PUE) with an amorphous reversible phase, the TRPU with a crystalline reversible phase shows a phase-separated structure and a phased transition temperature (Ttrans) at normal use temperature. The water swelling and water vapour permeability of both TRPU film and finished leather are found to depend on the inner structure of the polymers and the temperature. When the temperature exceeds the Ttrans, a significant increase of WVP from 4100g/m2/day to 10500g/m2/day was observed for finished leather in spite of some decrease of WVP compared with un-finished leather. Leather finished with common PUE appears to have a low WVP and only a slightly increased value over the temperature range. |
Note de contenu : |
- EXPERIMENTAL PROCEDURE : Material, preparation of polyurethane and testing - Film casting and leather specimen preparation - Differential Scanning Calorimetry (DSC) and
Dynamic Mechanical Thermal Analyzer (DMTA) - Water swelling of PU films - Measurement of water transport properties
- RESULTS AND DISCUSSION : Phase transition temperature of polyurethanes - Water swelling of PU films - Water vapour permeability
- Table 1 : Characteristics of the TRPU and PUE prepared
- Table 2 : Storage modulus of PU samples as a function of temperature
- Table 3 : Comparison of water swelling of different PU films |
En ligne : |
https://drive.google.com/file/d/1qQXbjgGgLXlKIkAE_ZSG7m0uac1UdoeO/view?usp=share [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39272 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 89, N° 3 (05-06/2005) . - p. 121-125