FOAM INSULATION UNIT

摘要

Insulating unit are disclosed which are prepared by a cavity-filling, fast-gelling rigid polyurethane foam based on a formulation comprising a polyol component which contains at least 5 weight percent of an amine-initiated polyols and 1.4 to 4 parts by weight of a catalyst package whereby the catalyst package contains at least one amine catalyst and the weight percent nitrogen present in the amine-initiated polyol to weight percent nitrogen present in the catalyst system is from 2 to 8. The formulation is injected into the cavity and the pressure in the cavity is subjected to reduced atmospheric pressure to achieve the rigid foam having a thermal conductivity of less than about 19 mW/mK at 10° C. average plate temperature.

主权项

1. A process for preparing an insulating unit comprising at least two side walls, a back wall and a top wall wherein each wall comprises a polyurethane foam between an inner lining and an outer lining and the side walls are connected to the back wall and the top wall at an angle between 85 and 95°; the back wall and the side walls have a height of between 0.5 and 3 meters and the side walls have a width of between 0.5 and 1.5 meters and the back wall has a width of between 0.5 and 2.0 meters and wherein the polyurethane foam disposed between the inner and outer liner has a thickness of 20 to 120 mm and is produced from a reaction mixture comprising;
(a) preparing a reactive foam-forming system comprising as components at least an organic polyisocyanate; a polyol formulation comprising a polyol component containing from 5 to 85 weight percent of at least one amine-initiated polyol, an nominal average functionality of 3 to 8 and an average hydroxyl number of from 200 to 850, from 1 to 5 parts by weight of a catalyst system per 100 parts by weight of the polyol component wherein the catalyst system comprises at least one amine catalyst, a non-chlorofluorocarbon physical blowing agent; and an amount of water that is less than 2 percent by weight based on the polyol formulation, wherein the weight percent of nitrogen in the formulation, excluding the weight of the blowing agent, derived from the polyol component (Npol) is from is from 1.4 to 5 and the ratio of Npol to the weight percent nitrogen from the catalyst system (Ncat) is from 2 to 8; (b) injecting the reactive foam-forming system at or above atmospheric pressure into a cavity, wherein the reactive foam-forming system forms a gel in no more than 30 seconds; (c) subjecting the cavity to a reduced atmospheric pressure; and (d) maintaining the reduced atmospheric pressure at least until the gel forms a closed cell rigid polyurethane foam, the foam having a density of from 28 to 40 kg/m3, an average cell diameter of less than about 250 microns, a thermal conductivity of less than about 19 mW/mK at 10° C. average plate temperature, according to ISO 12939/DIN. 52612.