PROCESS AND APPARATUS FOR THE PREPARATION OF A POLYURETHANE REACTION MIXTURE

摘要

The variations in the delivery rate of additive caused by fluctuations in a system for the preparation of a polyurethane reaction mixture from flowable reactants and an additive, in particular a blowing agent, are kept within negligible limits by subdividing the supply pipe (4) to the mixing head (6) into a main pipe (8) and a subpipe (9) and introducing the additive into the side stream, which is substantially smaller than the main stream.