Modified polyoxytetramethylene glycol and processes for its production

Claim 2

The modified polyoxytetramethylene glycol according to Claim 1, which has a molecular weight of from 1,000 to 5,000.

Claim 3

The modified polyoxytetramethylene glycol according to Claim 1, wherein n is from 4 to 20.

Claim 4

A process for producing a modified polyoxytetramethylene glycol having a main chain with a repeating structure comprising a polyoxytetramethylene group of the formula ⁅O(CH 2 ) 4 ⁆ n wherein n is from 3 to 28, and a dioxycarbonyl group of the formula wherein the oxytetramethylene group -O(CH 2 ) 4 -constitutes from 75.5 to 99.3 mol% and the dioxycarbonyl group constitutes from 24.5 to 0.7 mol%, which comprises subjecting a polyoxytetramethylene glycol of the formula H⁅O(CH 2 ) 4 ⁆ n OH wherein n is as defined above, to an ester exchange reaction with a carbonate of the formula wherein R is a bivalent aliphatic saturated C 2 -C 6 hydrocarbon group, or wherein each of R and R which may be the same or different is a monovalent aliphatic C 1 -C 6 hydrocarbon group or an aryl group, in a molar ratio of the polyoxytetramethylene glycol/the carbonate of from 0.1 to 1.0.

Claim 5

The process according to Claim 4, wherein the ester exchange reaction is conducted in the presence of from 0.001 to 0.5 mol%, based on the polyoxytetramethylene glycol, of an ester exchange catalyst.

Claim 6

A process for producing a modified polyoxytetramethylene glycol having a main chain with a repeating structure comprising a polyoxytetramethylene group of the formula ⁅O(CH 2 ) 4 ⁆ n wherein n is from 3 to 28, and a dioxycarbonyl group of the formula wherein the oxytetramethylene group -O(CH 2 )a.-constitutes from 75.5 to 99.3 mol% and the dioxycarbonyl group constitutes from 24.5 to 0.7 mol%, which comprises reacting a polyoxytetramethylene glycol of the formula H⁅O(CH 2 ) 4 ⁆ n OH wherein n is as defined above, with phosgene in the presence of an inert solvent, wherein the polyoxytetramethylene glycol and phosgene are mixed in a molar ratio of from 1.08 to 2.0, and then an organic base is added to conduct the reaction.

Claim 7

A process for producing a modified polyoxytetramethylene glycol having a main chain with a repeating structure comprising a polyoxytetramethylene group of the formula ⁅O(CH 2 ) 4 ⁆ n wherein n is from 3 to 28, and a dioxycarbonyl group of the formula wherein the oxytetramethylene group -O(CH 2 ) 4 -constitutes from 75.5 to 99.3 mol% and the dioxycarbonyl group constitutes from 24.5 to 0.7 mol%, which comprises reacting a polyoxytetramethylene glycol of the formula H⁅O(CH 2 ) 4 ⁆ n OH wherein n is as defined above, with trichloromethyl chloroformate in the presence of an inert solvent, wherein from 0.001 to 5.0% by weight, relative to trichloromethyl chloroformate, of pyridine, a pyridine derivative, quinoline, tetramethylurea, hexamethylphosphoric acid triamide and/or an amine of the formula R 1 R 2 R 3 N wherein R 1 is an alkyl group having from 1 to 12 carbon atoms, and each of R 2 and R 3 is an alkyl group having from 1 to 4 carbon atoms, provided that R 1 , R 2 and R 3 may be the same or different, is preliminarily added to polyoxytetramethylene glycol, then the polyoxytetramethylene glycol and trichloromethyl formate are mixed in a molar ratio of from 2.16 to 4.0, and then an organic base is added to conduct the reaction.

Claim 8

The process according to Claim 6 or 7, wherein the organic base is a pyridine, triethylamine, tri-n-propylamine or tri-n-butylamine.

Claim 9

The process according to Claim 8, wherein the pyridine is pyridine or a methyl-substituted pyridine having the methyl group at the 2-, 3-, 4-, 5- or 6-position.