Ethylene oxide/propylene oxide polyether polyols and polyurethanes made therefrom

摘要

Copolymers of propylene oxide and ethylene oxide have an inner block that contains from 65-90 weight percent oxyethylene units and from 10 to 35 weight percent oxypropylene units. This block has a molecular weight of from 150 to 350. The copolymer has an outer block which contains at least 95 weight % oxypropylene units and from 0 to 5% oxyethylene units. The equivalent weight of the copolymer is from 800 to 2000. The copolymers are useful in making polyurethane foams that have unexpectedly high tensile and/or tear strengths.

主权项

1. A propylene oxide/ethylene oxide copolymer containing two or more hydroxyl-terminated polyether chains extending from a residue of an initiator compound, wherein the polyether chains each contain an inner block and an outer block, wherein the inner block of each of said polyether chains has a molecular weight of from about 150 to 350 and contains from 10 to 35% by weight of oxypropylene units and from 65 to 90% by weight of oxyethylene units, and the outer block of each of said polyether chains contains from 95 to 100% by weight oxypropylene units and from 0 to 5% by weight oxyethylene units, and further wherein the propylene oxide/ethylene oxide copolymer has a hydroxyl equivalent weight of from 800 to 2000 and a total oxyethylene content of from 5 to 18% by weight.