| 摘要 |
Heat-hardenable aq. dispersion contains a base-neutralised urea-urethane reaction prod. from aa polyamine and a NCO-terminated urethane prepolymer contg. COOH gps. Neutralisation is sufficient to give a dispersion which can be diluted to any extent with water. At least part of the polyamine has >=3 amine gps. with reactive H, giving a urea-urethane with sufficient amino N carrying reactive H to give heat hardenability. The dispersion is a coating compsn., or can be used to cast thin films, or as an adhesive. The hardened films are resistant to water and alcohol, esp. isopropanol, and have better resistance to abrasion and better elastomeric properties. The dispersions are compatible with a wide range of pigments. |
