Substituted 1-oxy-4-acyloxypiperidines or 1-oxy-4-acylaminopiperidines of formula I
wherein R₁, R₂, R₃ and R₄ are independently hydrogen, alkyl or substituted alkyl, R₅ is hydrogen, alkyl, cycloakyl, allyl or benzyl, X is -O- or -NE-, E is hydrogen, akyl or cycloakyl, A is an n-valent aliphatic or aromatic hydrocarbon radical, and n is 1 to 4 are effective in providing melt flow stabilization to polymeric materials during processing.
式 I 的被取代的 1-氧-4-乙酰氧基
哌啶或 1-氧-4-乙酰
氨基
哌啶
其中 R₁、R₂、R₃ 和 R₄ 独立地是氢、烷基或取代烷基,R₅ 是氢、烷基、环烷基、烯丙基或苄基,X 是-O-或-NE-,E 是氢、烷基或环烷基,A 是正价脂肪族或芳香族烃基,n 是 1 至 4。