| abstract |
Commercially acceptable spandex can be prepared with greater efficiency, improved consistency and at lower costs from a high-solids content polyurethaneurea polymer solution. The polyurethaneurea is prepared using a combination of 4, 4'-MDI and 2,4'-MDI, and an amount of chain extenders and chain terminators such that the polymer solution, prior to spinning, is highly soluble and has an appropriate pre-spun IV and primary amine content. |