Abstract: A propylene polymer composition stabilized against oxidative degradation comprising(1) 100 parts by weight of a propylene polymer,(2) 0.001 to 5 parts by weight of a poly(tertiary-butylated p-vinyl phenol) composed substantially of monomeric units represented by the following formula (I) ##STR1## wherein R.sub.1 represents a hydrogen atom or a tertiary butyl group, and (3) 0.001 to 5 parts by weight of a dialkylthiodipropionate represented by the following formula (II)S--C.sub.2 H.sub.4 COOR).sub.2 (II)wherein R represents an alkyl group containing 10 to 20 carbon atoms.

Abstract: A stabilized synthetic polymer composition comprising(1) 100 parts by weight of a synthetic polymer,(2) 0.001 to 5 parts by weight of a poly(alkylated alkenylphenol) composed substantially of monomeric units represented by the following formula (I) ##STR1## wherein R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R.sub.1 represents an alkyl group having 1 to 18 carbon atoms; and R.sub.2 represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; and(3) 0.001 to 5 parts by weight of an auxiliary stabilizer selected from the group consisting of polyhydric alcohol esters of alkylthioalkanoic acids, polyesters of thiodipropionic acid and organic phosphite compounds.

Abstract: A novel composite is disclosed which comprises a specific metal-compound additive as well as a plastic material and gypsum and/or calcium sulfite. The composite is improved in that it emits very little or substantially no toxic gas such as sulfur dioxide and hydrogen sulfide when it is burned and when the ash thereof is contacted with water.