Castable thermosetting polyurethane polymer having improved heat stability
US5130404A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 1991 |
| Grant date | Jul 14, 1992 |
| Priority date | — |
| Expiry date | Jun 4, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G2150/20
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A castable thermosetting polyurethane polymer, having improved heat-stability characteristics, comprising (A) a polymeric methylene diisocyanate, (B) a propyleneoxide-extended polyol which is preferably a sugar-based polyol, (C) a polyether diol or triol, and (D) dipropylene glycol or diethylene glycol, in amounts respectively between about 35-45 parts by weight, 35-45 parts by weight, and 12-20 parts by weight, per 100 parts by weight of total diol and triol (resin) components, providing an NCO/OH ratio between about 1:1 and about 1.2:1, an effective polyurethane-catalyzing amount of (E) a urethane catalyst, and optionally comprising an effective amount of a drying agent, is disclosed. The cast polyurethane polymer of the invention withstands temperatures of 450.degree. F. (232.degree. C.) for 20 minutes without visual polymer degradation, whereas most other castable polyurethane systems degrade between 350.degree. F. and 375.degree. F., as a result of which heat-stability the polymer of the present invention is especially suitable for post finishing which involves the employment of higher temperatures, such as painting with thermosetting coatings, powder coating, and anodizing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.