Polyisocyanate based upon 4,4'- and 2,4'-diphenylmethane diisocyanates and use thereof in a rim process
US5350778A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1993 |
| Grant date | Sep 27, 1994 |
| Priority date | — |
| Expiry date | Oct 28, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G2120/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Novel liquid, room temperature polyisocyanate having isocyanate group contents of from 6 to 31% by weight, are prepared by reacting: PA0 a) a methylene-bis(phenyl isocyanate) containing PA1 1) from 65 to 90% by weight of the 4,4'-isomer, PA1 2) from 10 to 35% by weigh of the 2,4'-isomer, and PA1 3) no more than 2% by weight of the 2,2'-isomer, with the percents of components a)1), a)2), and a)3) totalling 100%, and PA0 b) a mixture of: PA1 1) one or more organic compounds having molecular weights of from 400 to 6000 and containing from 2 to 8 isocyanate reactive groups, and PA1 2) one or more organic diols having molecular weights of from 60 to 200, excluding tripropylene glycol, the weight ratio of component b)1) to b)2) being from 150:1 to 5:1. When used in a RIM process, molded products are obtained which have improved tear strength, improved flexural modulus, improved impact resistance, and improved tensile strength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.