PROCESS FOR PRODUCING POLYOXYMETHYLENE-POLYOXYALKYLENE COPOLYMERS
A process for producing a polyoxymethylene-polyoxyalkylene copolymer is provided. The process comprises reacting a polymer formaldehyde compound of an alkylene oxide and a specific component (X) in the presence of a double metal cyanide (DMC) catalyst. A polyoxymethylene-polyoxyalkylene copolymer can be obtained by means of such a process and to the use of same for producing a polyurethane polymer.
1 . A process for preparing a polyoxymethylene-polyoxyalkylene copolymer, the process comprising:
reacting a polymeric formaldehyde compound of an alkylene oxide and a component (X) in the presence of a double metal cyanide (DMC) catalyst;
wherein the polymeric formaldehyde compound has at least one terminal hydroxyl group;
wherein the component (X) comprises at least one terminal hydroxyl group, at least one terminal carboxyl group and/or at least one terminal thiol group;
wherein the theoretical molar mass of the polymeric formaldehyde compound is greater than the theoretical molar mass of the component (X);
wherein the component (X) is distinct from compounds of formula (I),
and wherein n in formula (I) is a natural number from 0 to 100.
2 . The process as claimed in claim 1 , wherein the component (X) comprises one to six terminal hydroxyl groups, one to six terminal carboxyl groups and/or one to six terminal thiol groups.
3 . The process as claimed in claim 1 , wherein the component (X) is one or more compounds selected from the group consisting of ethylene glycol, diethylene glycol, polyethylene glycol, methylpropylene glycol, dipropylene glycol, polypropylene glycol, butane-1,3-diol, butane-1,4-diol, 1,1,1-trimethylolpropane, glycerol, pentaerythritol, sorbitol, sucrose, xylitol, propane-1,2-diol, and propane-1,3-diol.
4 . The process as claimed in claim 1 , wherein the mole fraction of the component (X) is from 0.5 mol % to 95 mol % based on the sum of the molar amounts of the polymeric formaldehyde compound and the component (X).
5 . The process as claimed in claim 1 further comprises the steps of:
(α) initial charging of a suspension medium in a reactor; and
(γ) stepwise or continuous metered addition of the alkylene oxide during the reaction.
6 . The process as claimed in claim 5 , wherein in step (γ) the component (X) is metered in continuously or stepwise.
7 . The process as claimed in claim 5 , wherein in step (γ) the polymeric formaldehyde compound and the alkylene oxide are metered in continuously or stepwise.
8 . The process as claimed in claim 5 , wherein step (γ) is carried out at a temperature of 20° C. to 130° C.
9 . The process as claimed in claim 5 , wherein in step (α) the suspension medium contains no H-functional groups.
10 . The process as claimed in claim 9 , wherein in step (α) the suspension medium containing no H-functional groups is initially charged in the reactor together with DMC catalyst.
11 . The process as claimed in claim 10 , wherein the process further comprises:
(β) a subamount of alkylene oxide is added to the mixture from step (α) at a temperature of 20° C. to 120° C., wherein the addition of the alkylene oxide compound is then interrupted.
12 . The process as claimed in claim 1 , wherein the alkylene oxide is one or more compounds selected from the group consisting of ethylene oxide, propylene oxide, styrene oxide and cyclohexene oxide.
13 . A polyoxymethylene-polyoxyalkylene copolymer produced by the process as claimed in claim 1 .
14 . The polyoxymethylene-polyalkylene oxide copolymer as claimed in claim 13 , wherein the polyoxymethylene-polyalkylene oxide copolymer comprises an oxymethylene group content of 1% by weight to 70% by weight based on the polyoxymethylene-polyalkylene oxide copolymer product.
15 . A process for preparing a polyurethane polymer comprising reacting a polyisocyanate component with a polyol component, wherein the polyol component comprises the polyoxymethylene-polyoxyalkylene copolymer as claimed in claim 13 .
16 . The process as claimed in claim 1 , wherein the component (X) comprises at least one terminal hydroxyl group.
17 . The process as claimed in claim 2 , wherein the component (X) comprises at least one of
three to six terminal hydroxyl groups,
three to six terminal carboxyl groups and
three to six terminal thiol groups.
18 . The process as claimed in claim 3 , wherein the component (X) is one or more compounds selected from the group consisting of polypropylene glycol, 1,1,1-trimethylolpropane, glycerol and sorbitol.
19 . The process as claimed in claim 4 , wherein the mole fraction of component (X) is from 10 mol % to 85 mol % based on the sum of the molar amounts of the polymeric formaldehyde compound and the component (X).
20 . The process as claimed in claim 6 , wherein in step (γ) component (X) is metered in continuously.