摘要:
This invention relates to a process for the preparation of stable dispersions of hydroxyl-containing polyhydrazodicarbonamides in a hydroxyl-containing compound. The dispersions are prepared by the reaction of organic isocyanates, isocyanate-reactive compounds having a molecular weight in the range from 400 to 10,000, relatively low molecular weight isocyanate-reactive compounds, and hydrazines or hydrazides. This invention further relates to the dispersions prepared by said process, the use of the dispersions to prepare polyurethane foams having exceptional hardness, and the foams prepared thereby.
摘要:
Stable finely-divided dispersions of polyureas and/or polyhydrazodicarbonamides in a hydroxyl-group-containing material are made by reacting (i) an isocyanate with (ii) a compound selected from polyamines, hydrazines, hydrazides and mixtures thereof in the presence of (iii) a hydroxyl compound selected from polyethers, polyesters, polyester amides, polycarbonates and mixtures thereof and (iv) a catalyst. The catalyst is a compound which catalyzes the reaction of isocyanate groups with hydroxyl groups. The catalyst is used in a quantity of at least 50 parts per million parts of (i), (ii) and (iii). These dispersions are particularly useful in the production of polyurethanes.
摘要:
The present invention relates to a process for the production of stable dispersions of polyureas and/or polyhydrazodicarbonamides in a hydroxyl-group-containing material by reacting an organic di- or polyisocyanate with a composition selected from the group consisting of polyamines containing primary and/or secondary amine groups, hydrazines, hydrazides, and mixtures thereof, in said hydroxyl-group containing material, in the presence of a dispersion stabilizing compound.
摘要:
This invention relates to polyurethane foams which exhibit decreased aldehyde emission, to a process of preparing these polyurethane foams, and to a method of decreasing aldehyde emissions in foams. The polyurethane foams herein additionally comprise a small quantity of a polyhydrazodicarbonamide dispersion polyol to the isocyanate-reactive component, or a trimerized hexamethylene diisocyanate to the polyisocyanate component.
摘要:
The present invention relates to an improved process for preparing foams comprising reacting polyisocyanates with an in situ produced stable low solids dispersion of polyureas and/or polyhydrazodicarbonamides in a hydroxyl-group-containing material as a dispersing agent by reacting:(a) organic polyisocyanates with(b) a member selected from the group consisting of (i) polyamines containing primary and/or secondary amino groups, (ii) hydrazines, (iii) hydrazides, or (iv) mixtures thereof, in(c) said hydroxyl-group-containing material.
摘要:
This invention relates to polyurethane foams which exhibit decreased aldehyde emission, to a process of preparing these polyurethane foams, and to a method of decreasing aldehyde emissions in foams. The polyurethane foams herein additionally comprise a small quantity of a polyhydrazodicarbonamide dispersion polyol to the isocyanate-reactive component, or a trimerized hexamethylene diisocyanate to the polyisocyanate component.