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Preparation and characterization of waterborne hyperbranched polyurethane - urea and their hybrid coatings / Pion Florian in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4517–4527 Titre : Preparation and characterization of waterborne hyperbranched polyurethane - urea and their hybrid coatings Type de document : texte imprimé Auteurs : Pion Florian, Auteur ; Kishore K. Jena, Auteur ; Shaik Allauddin, Auteur Année de publication : 2010 Article en page(s) : pp. 4517–4527 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Waterborne  Hybrid  Coatings Résumé : A series of novel waterborne hyperbranched polyurethane-urea (WHBPU) were prepared with different chain extenders (diamine, diol, and siloxane) by a systematic reaction process. Initially, the hyperbranched polyester polyol was prepared by reacting polytetramethyleneglycol (PTMG)-1000 with 2,2-bis(hydroxymethyl) propionic acid (DMPA) in a molar ratio of 1:14 (3rd generation) at 160 °C by one pot synthesis. This was reacted with an adduct of isophorone diisocyanate (IPDI) and DMPA with NCO:OH mole ratio of 1.6:1. Then 50% of free NCO in these prepolymers was reacted with three different chain extenders (diol, diamine and APTES). This reaction mixture was neutralized with triethyl amine and another 50% of free NCO was chain extended with isophorone diamine during water dispersion. The obtained polyester was characterized with Fourier transform-infrared spectroscopy (FT-IR), 1H and 13C NMR, respectively. The properties of WHBPU and their hybrid coatings were studied by FT-IR, 1H NMR, thermogravimetric analyzer (TGA), dynamic mechanical, and thermal analyzer (DMTA), and the contact angle measurement. TGA and DMTA results confirmed that these coatings have good thermal and mechanical properties. The onset degradation temperature of the WHBPU without APTES starts in between 200 and 250 °C, whereas the APTES chain extended WHBPU starts at 250 °C. Tg of WHBPU without APTES varies between 106 and 126 °C, while 129 °C for APTES chain extended WHBPU. The conditions for the reproducible preparation of suitable products have been found and optimized. They enable the tuning of their properties according to the intended use. The aim of the prepared WHBPU films is long-term use as thermal and mechanical resistant systems. Along with these property APTES cross-linked system, the hydrophobic silica-rich surface is likely to be inhibited the hybrid films upon exposure to an aqueous environment. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900840g [article] Preparation and characterization of waterborne hyperbranched polyurethane - urea and their hybrid coatings [texte imprimé] / Pion Florian, Auteur ; Kishore K. Jena, Auteur ; Shaik Allauddin, Auteur . - 2010 . - pp. 4517–4527. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4517–4527 Mots-clés : Waterborne  Hybrid  Coatings Résumé : A series of novel waterborne hyperbranched polyurethane-urea (WHBPU) were prepared with different chain extenders (diamine, diol, and siloxane) by a systematic reaction process. Initially, the hyperbranched polyester polyol was prepared by reacting polytetramethyleneglycol (PTMG)-1000 with 2,2-bis(hydroxymethyl) propionic acid (DMPA) in a molar ratio of 1:14 (3rd generation) at 160 °C by one pot synthesis. This was reacted with an adduct of isophorone diisocyanate (IPDI) and DMPA with NCO:OH mole ratio of 1.6:1. Then 50% of free NCO in these prepolymers was reacted with three different chain extenders (diol, diamine and APTES). This reaction mixture was neutralized with triethyl amine and another 50% of free NCO was chain extended with isophorone diamine during water dispersion. The obtained polyester was characterized with Fourier transform-infrared spectroscopy (FT-IR), 1H and 13C NMR, respectively. The properties of WHBPU and their hybrid coatings were studied by FT-IR, 1H NMR, thermogravimetric analyzer (TGA), dynamic mechanical, and thermal analyzer (DMTA), and the contact angle measurement. TGA and DMTA results confirmed that these coatings have good thermal and mechanical properties. The onset degradation temperature of the WHBPU without APTES starts in between 200 and 250 °C, whereas the APTES chain extended WHBPU starts at 250 °C. Tg of WHBPU without APTES varies between 106 and 126 °C, while 129 °C for APTES chain extended WHBPU. The conditions for the reproducible preparation of suitable products have been found and optimized. They enable the tuning of their properties according to the intended use. The aim of the prepared WHBPU films is long-term use as thermal and mechanical resistant systems. Along with these property APTES cross-linked system, the hydrophobic silica-rich surface is likely to be inhibited the hybrid films upon exposure to an aqueous environment. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900840g

Synthesis and characterization of hyperbranched polyurethane hybrids using tetraethoxysilane (TEOS) as cross-Linker / Kishore K. Jena in Industrial & engineering chemistry research, Vol. 47 N° 23 (Décembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N° 23 (Décembre 2008) . - p. 9214–9224 Titre : Synthesis and characterization of hyperbranched polyurethane hybrids using tetraethoxysilane (TEOS) as cross-Linker Type de document : texte imprimé Auteurs : Kishore K. Jena, Auteur ; K. V. S. N. Raju, Auteur Année de publication : 2009 Article en page(s) : p. 9214–9224 Note générale : Chemistry engineering Langues : Anglais (eng) Mots-clés : Hyperbranched  Polyurethane Résumé : Organic−inorganic hybrid coatings were derived from a hydroxyl-terminated hyperbranched polyester, 3-isocyanatopropyl triethoxysilane (ISPTES), and then cross-linked with various percentages of SiO2. This system was able to cross-link by hydrolysis of a tetraethoxysilane group in room temperature and humid conditions and then at 120 °C for 12−14 h, forming a three-dimensional hybrid structure, where the organic and inorganic phases were bonded covalently. The main focus of this work was to study the change of properties of the coating with SiO2 modification. These hybrid coatings were also characterized by using NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamical mechanical thermal analyzer (DMTA), thermal analysis (TGA), and tensile strength. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800884y [article] Synthesis and characterization of hyperbranched polyurethane hybrids using tetraethoxysilane (TEOS) as cross-Linker [texte imprimé] / Kishore K. Jena, Auteur ; K. V. S. N. Raju, Auteur . - 2009 . - p. 9214–9224. Chemistry engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N° 23 (Décembre 2008) . - p. 9214–9224 Mots-clés : Hyperbranched  Polyurethane Résumé : Organic−inorganic hybrid coatings were derived from a hydroxyl-terminated hyperbranched polyester, 3-isocyanatopropyl triethoxysilane (ISPTES), and then cross-linked with various percentages of SiO2. This system was able to cross-link by hydrolysis of a tetraethoxysilane group in room temperature and humid conditions and then at 120 °C for 12−14 h, forming a three-dimensional hybrid structure, where the organic and inorganic phases were bonded covalently. The main focus of this work was to study the change of properties of the coating with SiO2 modification. These hybrid coatings were also characterized by using NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamical mechanical thermal analyzer (DMTA), thermal analysis (TGA), and tensile strength. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800884y