Abstract A polymer consisting mainly of recurring oxymethylene units, and also containing at least 0,1% of recurring oxyalkylene or substituted oxyalkylene units each containing two or more adjacent carbon atoms, is obtained by copolymerizing trioxane and a cyclic ether containing two or more adjacent carbon atoms. The copolymerization is carried out in the presence of a boron fluoride co-ordination complex with an organic compound in which oxygen is the donor atom. The copolymer may contain up to 15% of the oxyalkylene units. The thermal stability of the copolymer may be improved by reacting it with a isocyanate. In examples, copolymers are obtained by copolymerizing trioxane with ethylene oxide, dioxolane, neopentyl formal or pentaerythritol diformal, and in some instances the copolymers are reacted with toluene-2, 4-di-isocyanate. Other cyclic ethers and isocyanates are mentioned. Specification 877,820 is referred to.
THE RESINOUS REACTION PRODUCT OF AN ISOCYANATE WITH A RESINOUS OXYMETHYLENE CYCLIC ETHER COPOLYMER CONTAINING FROM 60 TO 99.9 MOL PERCENT OF RECURRING OXYMETHYLENE UNITS AND 0.4 TO 40 MOL PERCENT OF MONOMERIC UNITS OBTAINED BY THE OPENING OF SAID CYCLIC ETHERS BETWEEN A CARBON ATOM AND AN ETHERIC OXYGEN ATOM, SAID CYCLIC ETHER HAVING AT LEAST TWO ADJACENT CARBON ATOMS, THE AMOUNT OF SAID ISOCYANATE BEING SUFFICIENT TO STABILIZE SAID COPOLYMER BUT NOT IN EXCESS OF 10 WEIGHT PERCENT THEREOF.
Claim 2
Dependent Claim
81 words
THE RESINOUS REACTION PRODUCT OF AN ISOCYANATE WITH A RESINOUS OXYMETHYLENE CYCLIC ETHER COPOLYMER CONTAINING FROM 60 TO 99.9 MOL PERCENT OF RECURRING OXYMETHYLENE UNITS AND 0.4 TO 40 MOL PERCENT OF MONOMERIC UNITS OBTAINED BY THE OPENING OF SAID CYCLIC ETHERS BETWEEN A CARBON ATOM AND AN ETHERIC OXYGEN ATOM, SAID CYCLIC ETHER HAVING AT LEAST TWO ADJACENT CARBON ATOMS, THE AMOUNT OF SAID ISOCYANATE BEING SUFFICIENT TO STABILIZE SAID COPOLYMER BUT NOT IN EXCESS OF 10 WEIGHT PERCENT THEREOF.