Abstract: A stabilized polymeric composition comprising an acetal polymer and as stabilizer a copolymer R--D--A--B--D--R, in which:A is a block of recurring units: ##EQU1## B is a block of recurring units: ##EQU2## D is a block of recurring units: ##EQU3## R is an ester, ether or urethane group wherein PM.sub.1 and PM.sub.2 are linear polymethylene chains having 2 to 13 and 3 to 13 carbon atoms, respectively, non substituted or having at least one hydrogen atom replaced by an alkyl, aryl, alkylaryl or cycloalkyl radical; the said stabilizer being used in a proportion of from 0.02 to 12 parts by weight to 100 parts by weight an acetal polymer.

Abstract: Polymeric materials of improved dyeability and other properties are provided which consist of polypropylene or polyester material and a small percentage of a nitrile which contains 20-75 carbon atoms and 2-4 nitrile groups in the molecule. Processes for preparing these improved polymeric materials and methods for dyeing these materials are also provided.