PURPOSE: To improve melt processing properties of a linear alternating copolymer by blending a partially neutralized polymer of an alpha-olefin and an unsaturated acid with a linear alternating copolymer of carbon monoxide and an ethylenically unsaturated compound.

CONSTITUTION: A polyketone polymer composition contains a linear alternating copolymer of carbon monoxide and at least one ethylenically unsaturated hydrocarbon as the major component and a partial non-alkali metal salt of a polymer of an alpha-olefin and an alpha, beta-ethylenically unsaturated carboxylic acid as the minor component. Preferably 10-90% of the original carboxyl groups of the partially neutralized polymer is neutralized with an ionizable zinc compound. The minor component is preferably present in an amount of 0.2-35 wt.% based on the total composition. Also the minor component is preferably a polymer having at least 80 mol% of ethylene and 1-20 mol% of methacrylic acid based on the total polymer in which 35-75% of the carboxyl groups have been neutralized with an ionizable zinc compound.