| abstract |
Syntactic polyurethanes are prepared by mixing hollow microspheres with polyurethanes by a process in which, in a first step, the polyurethane system components are reacted and, in a second step, the feeding of the hollow microspheres is effected in a mixing apparatus, the mixing apparatus being free of dead space and comprising n i) a mixing pot, n ii) a feed for polyurethane, n iii) a feed for hollow microspheres, n iv) a stirring element and n v) an outlet orifice. |