Water dispersible polyurethane and process for preparation thereof
US5306764A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 3, 1992 |
| Grant date | Apr 26, 1994 |
| Priority date | — |
| Expiry date | Sep 3, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D175/16
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Amine-containing, water dispersible polyurethanes made by the following process: (1) in a reactive diluent such as acrylate, methacrylate, acrylonitrile monomer, low viscosity epoxy compound or epoxy resin, or mixture thereof, using an excess amount of polyisocyanate to react with polyol to form NCO-terminated urethane prepolymer; (2) adding hydroxy alkyl acrylate or hydroxy alkyl methacrylate monomer to react with the prepolymer in step (1) to convert its -NCO end group into alkyl acrylate or alkyl methacrylate end group; and (3) using an excess amount of polyamine to react with the alkyl (meth)acrylate-terminated prepolymer in step (2) and the reactive diluent and the residual hydroxy-containing monomer in step (2), if any. The polyurethane can be mixed with a crosslinking agent having multi-epoxy or blocked polyisocyanate functionalities, to prepare a stable aqueous coating composition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.