| 摘要 |
Compounds of the formula wherein R is alkyl of 1 to 8 carbon atoms and X is hydrogen or -OR, are useful, in combination with hindered-phenol antioxidants, for inhibiting thermal degradation of polyolefins, especially polypropylene, in contact with copper as metal, alloys, oxides, or salts. Such compounds can be prepared by reacting hydrazine wit a naphthoic acid ester which may have an alkoxy group in the 3- position to form an intermediate which reacts with 3-alkoxy-2-naphthoyl chloride to form said compounds. |
