abstract |
The present invention relates an MDI-based isocyanate-terminated prepolymer suitable for preparing a hydrophilic polyurethane polymer. The MDI-based composition comprises a prepolymer obtained by reacting isocyanate mixture comprising 2,4′-methylene diphenylisocyanate (MDI) and 4,4′-methylene diphenylisocyanate in a molar ratio of from 25:75 to 80:20 with a polyether polyol having an oxyethylene content of at least 30 percent by weight. |