Preparation of poly(ether-urethanes) from cyclic ethers and organic isocyanates
AssigneeE. I. Du Pont de Nemours and Company
InventorNeville Everton Drysdale
Life of this patent
Estimating the term…
Abstract
Poly(ether-urethanes) can be made from cyclic ethers and organic isocyanates by using selected metal compounds as catalysts. Polymers useful as thermoplastic elastomers, spandex fibers or urethane rubbers can be made by reacting diisocyanates containing functional groups with a tetrahydrofuran, especially tetrahydrofuran itself. The invention also discloses an improved process for the cationic polymerization of a cyclic ether by using an organic isocyanate.
Claims39
An improved process for the cationic polymerization of a cyclic ether selected from the group consisting of oxetane, tetrahydrofuran, 1,3-dioxolane, 1,3,5-trioxane, and oxepane, wherein the improvement comprises, carrying out the cationic polymerization in the presence of an organic isocyanate, provided that a cationic catalyst does not substantially react with or cause substantial side reaction of the organic isocyanate under the process conditions, so that less than 10 mole percent of the isocyanate groups present react with the cationic catalyst or undergo said side reactions during said polymerization, and a poly(ether-urethane) is produced.
A process for the production of poly(ether-urethanes), comprising, contacting a cyclic ether selected from the group consisting of oxirane, oxetane, tetrahydrofuran, 1,3-dioxolane, 1,3,5-trioxane, and oxepane, an organic isocyanate of the formula A(NCO).sub.x and a catalyst of the formula MZ.sub.s .multidot.Q.sub.t, wherein:
- M is a metal selected from the group consisting of cobalt, tungsten, vanadium, niobium, strontium, barium, scandium, yttrium, the rare earth metals, titanium, zirconium, hafnium, chromium, molybdenum, tantalum, rhenium, iron, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, mischmetall, copper, gold, zinc, cadmium, mercury, aluminum, gallium, indium, thulium, germanium, tin, lead, arsenic, antimony and bismuth;
- at least one of Z is an anion of the formula --OSO.sub.2 R.sup.5, wherein R.sup.5 is perfluoroalkyl containing 1 to 12 carbon atoms or part of a fluorinated group wherein the carbon atoms alpha and beta to the sulfonate group are together bonded to at least four fluorine atoms, or tetrafluoroborate, and the remainder of Z is oxo or one or more monovalent anions;
- s is 1 when M is silver;
- s is 2 when M is strontium, barium, copper, cobalt, rhodium, iridium, palladium, chromium, zinc, cadmium or mercury;
- s is 3 when M is scandium, yttrium, a rare earth metal, mischmetall, arsenic, antimony, bismuth, gold, iron, ruthenium, osmium, aluminum, gallium, indium or thulium;
- s is 4 when M is titanium, zirconium, platinum, hafnium, molybdenum, germanium, tin or lead;
- s is 5 when M is rhenium, vanadium, niobium or tantalum;
- s is 6 when M is tungsten;
- Q is a neutral ligand;
- t is 0 or an integer of 1 to 6;
- each A is independently an organic radical having x free valencies;
- each x is independently 1, 2, 3, 4, 5 or 6;
- and provided that:
- A is bound to isocyanate groups through a carbon atom;
- and each oxo present as part of Z is considered to account for two of s;
- and wherein after contact has occurred the resulting product of the polymerization is further contacted with a proton donor to produce poly(ether-urethane).
Dependencies are inferred from the claim text.