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Thermoreversible Poly(isopropyl lactate diol) - based polyurethane hydrogels / Luiza M. Gradinaru in Industrial & engineering chemistry research, Vol. 51 N° 38 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 38 (Septembre 2012) . - pp. 12344-12354 Titre : Thermoreversible Poly(isopropyl lactate diol) - based polyurethane hydrogels : Effect of isocyanate on some physical properties Type de document : texte imprimé Auteurs : Luiza M. Gradinaru, Auteur ; Constantin Ciobanu, Auteur ; Stelian Vlad, Auteur Année de publication : 2012 Article en page(s) : pp. 12344-12354 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Physical  properties Résumé : A series of polyurethanes were synthesized from poly(isopropyl lactate)diol, poly(ethylene oxide)― poly(propylene oxide)―poly(ethylene oxide) triblock copolymer, and different aliphatic diisocyanates. The chemical structure and molecular characteristics were investigated by 1H NMR, FT-IR, and GPC analysis. The effect of the isocyanate moiety on the polymer properties was studied. The wetting properties were evaluated from the contact angle determination. The obtained water-soluble polyurethanes present very low critical micelle concentration as determined by surface tension measurements. Aqueous solutions of these polyurethanes underwent a sol―gel―sol transition in a certain range of temperature, as a function of their chemical composition. The gelation for aqueous polyurethane solutions has been also realized under isothermal condition, and the viscoelastic properties of the hydrogels at 37 °C were investigated. The chemical structure of the diisocyanates influences the gelation process as well as the properties of the polyurethane hydrogels. These polyurethane properties might aid in devising new theoretical and practical approaches in many areas, such as pharmacology and materials fabrication. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26399686 [article] Thermoreversible Poly(isopropyl lactate diol) - based polyurethane hydrogels : Effect of isocyanate on some physical properties [texte imprimé] / Luiza M. Gradinaru, Auteur ; Constantin Ciobanu, Auteur ; Stelian Vlad, Auteur . - 2012 . - pp. 12344-12354. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 38 (Septembre 2012) . - pp. 12344-12354 Mots-clés : Physical  properties Résumé : A series of polyurethanes were synthesized from poly(isopropyl lactate)diol, poly(ethylene oxide)― poly(propylene oxide)―poly(ethylene oxide) triblock copolymer, and different aliphatic diisocyanates. The chemical structure and molecular characteristics were investigated by 1H NMR, FT-IR, and GPC analysis. The effect of the isocyanate moiety on the polymer properties was studied. The wetting properties were evaluated from the contact angle determination. The obtained water-soluble polyurethanes present very low critical micelle concentration as determined by surface tension measurements. Aqueous solutions of these polyurethanes underwent a sol―gel―sol transition in a certain range of temperature, as a function of their chemical composition. The gelation for aqueous polyurethane solutions has been also realized under isothermal condition, and the viscoelastic properties of the hydrogels at 37 °C were investigated. The chemical structure of the diisocyanates influences the gelation process as well as the properties of the polyurethane hydrogels. These polyurethane properties might aid in devising new theoretical and practical approaches in many areas, such as pharmacology and materials fabrication. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26399686