| 摘要 |
<p>Process for the preparation of a nylon block copolymer in which two or more reaction streams are combined, which reaction streams contain one or more polyols and/or polyamines, lactam-blocked polyisocyanates and catalysts, which may be dissolved in lactam or not, the catalysts and lactam-blocked polyisocyanates being present in different streams, in which the flows, whether or not pre-mixed, are metered to an extrusion device having a feed zone temperature of 80-180 °C and a cylinder temperature of 185-300 °C. The advantage is that the reaction rate increases in comparison with the RIM process, but also that nylon block copolymers with improved impact strength are obtained while the elastomer content remains unchanged.</p> |
