Stabilized polyacetal compositions

Claim 1

A thermoplastic polyacetal composition consisting essentially of (a) 0.1-10 weight percent of at least one compound selected from the group consisting of polymers and oligomers containing both hydroxy groups and at least one other functional group that is a stronger Lewis base than the hydroxy groups, and (b) 90-99.9 weight percent of at least one polyacetal polymer, provided that the above-stated percentages are based on the total amounts of components (a) and (b) only, provided further that the atoms in the backbone of the polymer or oligomer to which the hydroxy groups are attached, directly or indirectly, are separated by not more than twenty chain atoms; provided further that the quantity of the at least one other functional group is up to 50 equivalent percent of the number of equivalents of hydroxy groups in the component (a); and provided further that the component (a) is substantially free of acidic materials.

Claim 22

A method of preparing the composition or claims 1, 2 or 3 comprising mixing the hydroxy containing compound with the polyacetal polymer at a temperature above the melting points of the components or the composition and below the temperature at which degradation of the components will occur.