NON-ELASTOMERIC POLYURETHANE COMPOSITIONS

1365780 Polyurethanes DOW CHEMICAL CO 31 Aug 1972 [9 Sept 1971] 40385/72 Heading C3R Solid, dense (i.e. having a density of at least 1 g./c.c.), rigid, non-elastomeric (i.e. having an elongation value of less than 80%) polyurethane resins comprise the rapid-set reaction products of (A) a polyetherpolyol having 3 to 8 OH groups and a hydroxyl equivalent of 75 to 230 and (B) an organic polyisocyanate in admixture with (c) a liquid having a b.p. above 150‹ C. selected from hydroxyl containing polyoxyalkylene compounds having a M.W. above 700, ester modified polyoxyalkylene compounds having a M.W. above 700, non-hydroxyl containing polyoxyalkylene compounds, fatty oils, fatty acids, organic phosphates, organic phosphites, organic phosphonates, cyclic ethers, non- ester-containing aromatic compounds, hydrogenated aromatic compounds, halogenated aliphatic compounds, cyclic sulphones, organic carbonates and mixtures thereof and (D) anon- amine-containing catalyst for promoting the urethane condensation reaction, (A) and (B) providing an NCO/OH ratio of 0À8 to 2À0 : 1, component (C) providing 20 to 50% of the total weight of (A), (B) and (C) and component (D) providing 0À2 to 10% of the total weight of (A), (B) and (C) with the provisions that (1) when (C) is a halogenated aliphatic compound it provides 0À2 to 50% of the total weight of (A), (B) and (C), (2) when (C) is a halogenated aliphatic compound containing OH groups with an OH equivalent of less than 500 if provides 0À2 to 5% of the total weight of (A), (B) and (C) and (3) when (C) is a non-ester-containing aromatic or a halogenated aliphatic compound the catalyst (D) provides 0À01 to 10% of the total weight of (A), (B) and (C). The components (A) and (B) are those commonly used in the preparation of polyurethanes. Numerous examples of component (C) are listed and the use thereof exemplified. The catalyst (D) may be a compound of tin, zinc, lead, mercury, cadmium, bismuth, cobalt, manganese, antimony or iron, the use of lead octoate and stannous octoate being exemplified. The solid resins vary from transparent solids to white or off-white opaque solids and may take the form of bearing surfaces, annular spacers, decorative objects, furniture or furniture components, gears or other machine components, threaded protective plugs and caps.