| 摘要 |
A polyurea foam is prepared by reacting an aromatic polyisocyanate, as isocyanate component, with a composition containing water, a catalyst and a flame retardant, as water component. Various surfactants have been found which, when incorporated in the water component, enable a stable emulsion to be formed. This enables the flame retardant to be incorporated into the water component and not, as previously, into the isocyanate component and it thus becomes possible to use less isocyanate component in relation to water component than was previously necessary. The water component containing a tris(haloalkyl) phosphate as flame retardant and an aliphatic amine or imidazole as catalyst is also provided, in the form of a stable aqueous emulsion. Suitable surfactants are blends of fatty acid esters and polyalkylene ethers of a mixture of sorbitan mono-oleate and an ethoxylated sorbitan mono-oleate. |
