| 摘要 |
Described herein are compositions comprising (a) 92 to 99 weight percent, of polyoxymethylene with number average molecular weight from 65,000 to 250,000 g/mole; and (b) 1 to 8 weight percent of an imidized acrylic resin obtained by treating an acrylic polymer with a monoalkyl amine, wherein the weight percents of a and b are based on their combined weight, and monoalkyl group has from one to five carbon atoms, the degree of imidization is 20% to 100% and the acid level is from 0 to about 2 weight percent of the imidized acrylic resin. The composition has significantly higher heat deflection temperature than the neat polyoxymethylene. Processes of increasing heat deflection temperature of POM compositions are described herein by blending (a) and (b), wherein the resultant melt-mixed composition has a 200% increase or greater in time to 5% creep strain relative to the same melt-mixed composition lacking (b).
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