Patent ID: 8742065

Claim:
An oxymethylene polymer which is a homopolymer or copolymer in which the molar ratio of comonomer units to oxymethylene units is less than 0.008 and which has an at least bimodal molecular weight distribution, wherein the proportion of low molecular weight oxymethylene polymers having molecular weights below 10,000 Dalton is from 1 to 5% by weight, based on the total mass of the oxymethylene polymer the oxymethylene polymer being formed by a process wherein a monomer that forms formaldehyde units is combined optionally together with a comonomer that forms C—C units and together with a chain-transfer agent and a cationic polymerization initiator to form a polymerization mixture in such a way that first a precipitation polymerization is effected homogeneously and, following a period of time the first polymerization is stopped by addition of a basic compound, a temperature profile of the first polymerization being adjusted the period of time being selected so as to stop the first polymerization so that the oxymethylene polymer has a content of low molecular weight constituents of from 1 to 5% by weight.