Water-blown polyurethane sealing devices and compositions for producing same
US5539010A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1995 |
| Grant date | Jul 23, 1996 |
| Priority date | — |
| Expiry date | Oct 30, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G2190/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Disclosed as a particular isocyanate prepolymer composition particularly suitable for use in polyurethane compositions having particular applicability for producing microcellular molded polyurethane articles particularly suitable for use as sealing devices. In particular, the isocyanate prepolymer composition is the result of reacting an isocyanate blend (a) having PA1 (i) 0 to 10 pbw 2,4'-diphenylmethane diisocyanate; PA1 (ii) 40 to 90 pbw 4,4'-diphenylmethane diisocyanate; PA1 (iii) 1 to 10 pbw 3-ring oligomers of polymethylene polyphenyl polyisocyanate; PA1 (iv) 1 to 20 pbw of n-ring oligomers of polymethylene polyphenyl polyisocyanate (n being greater than 3); and PA1 (v) 1 to 10 pbw of a mixture of uretonimine with from 5 to 50 parts by weight of a propoxylated propylene glycol (b) having a number average molecular weight of between 2000 and 6000, and a hydroxyl number of between 10 to 75. The resulting isocyanate prepolymer (I) has a free NCO of from 20 to 30 and a viscosity of from 50 to 500 cPs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.