Waterborne polyurethane dispersions obtained by the acetone process: A study of colloidal features |
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Authors: | H. Sardon L. Irusta M. J. Fernández‐Berridi J. Luna M. Lansalot E. Bourgeat‐Lami |
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Affiliation: | 1. Departamento de Ciencia y Tecnología de Polímeros e Instituto de Materiales Poliméricos (POLYMAT), Facultad de Química UPV/EHU, 20018 Donostia;2. Laboratoire de Chimie, Catalyse, Polymères et Procédés (C2P2), Université de Lyon, Univ. Lyon 1, CPE Lyon, CNRS UMR 5265, F‐69616 Villeurbanne, France |
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Abstract: | Waterborne polyurethane (PU) dispersions were prepared from isophorone diisocyanate (IPDI), 2‐bis(hydroxymethyl) propionic acid (DMPA), 1,4‐butane diol (BD), poly(propylene glycol) (PPG), and triethylamine (TEA) by means of phase inversion through the acetone process. Changes in DMPA content, initial PU content in acetone, phase‐inversion temperature, evaporation conditions, and solvent nature were found to have a great impact on dispersion properties. Using a DMPA concentration of 0.30 mmol/gpol, stable PU dispersions could only be obtained when the initial PU content in acetone was at least 60 wt %, and phase‐inversion temperature was lower than 30°C. However, when increasing the PU content to 75 wt %, stable dispersions were obtained using DMPA concentrations three times lower. Finally, viscosity curves during the water addition step as well as a phase diagram were determined to understand the particle formation mechanism. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 |
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Keywords: | waterborne polyurethanes acetone process emulsification particle size distribution phase diagrams |
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