Urethane-modified carbodiimide-isocynurate foams prepared from TDI-rich isocyanates
US3994837A · kind A · utility
7Cited by
5References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1974 |
| Grant date | Nov 30, 1976 |
| Priority date | — |
| Expiry date | Oct 2, 1994 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S521/902
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Rigid cellular foams characterized by carbodiimide linkages exhibit low friability and excellent flame retardancy when prepared from isocyanates rich in toluene diisocyanate. The forms hereof are prepared by the catalytic condensation of the isocyanates by using either (1) isocyanate quasi-prepolymers or (2) a two-stage process wherein isocyanate and polyol are first reacted to form a urethane-containing intermediate having free isocyanate groups and then the remaining isocyanate groups are converted to carbodiimide groups and isocyanurate groups by the catalytic condensation thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.