摘要 |
Siloxane-urea copolymers are easily prepared by reacting a bis- or poly[azasilacyclopentyl]-terminated compound with a hydroxyl-functional compound followed by reaction with di- or polyisocyanate. When a bis[hydroxyl]-functional compound is used, the resulting polymer may be reacted with additional di- or polyisocyanate, optionally in the presence of additional isocyanate-reactive compounds such as chain extenders.
|