[article]
Titre : |
The effect of isocyanate index -NCO/-OH on the structure of polyurethane dispersion |
Type de document : |
texte imprimé |
Auteurs : |
Zhou Ming, Auteur ; Jiang Denggao, Auteur ; Hou Cuihong, Auteur |
Année de publication : |
2002 |
Article en page(s) : |
p. 33-40 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Polyurethane water-borne dispersions with different isocyanate index where prepared by using branched chain compound polyether under the same process conditions. With the increment of isocyanate index, pattern of dispersion granules turned from disorder linear spiral wound to inner molecular spherical concentration. At high Ri values, viscosity of dispersions increased with the increment of temperature during some temperature range. At room temperature, affected by the low Tgs ( glass transition temperature ) in soft segment, the polymers molecules were in an non-crystal state. With the increment of isocyanate index, polyesters inner molecular stress increased, when it was heated,the film cracked due to stress transition. Tgs between soft and hard segments are similar, so micro-phase separation was further enchanced. |
Note de contenu : |
- Experimental : Main raw material - Preparation of PU dispersion - Characterization
- Results and discussion : Effect of Ri value on PU dispersions surface structure - Surface structure of filmed polymers
- Phase inversion of polymer dispersions |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=12388 |
in PAINTINDIA > Vol. LII, N° 12 (12/2002) . - p. 33-40
[article]
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