Pentaerythritol co-esters derived from pentaerythritol, (3-alkyl-4-hydroxyphenyl)-alkanoic acids and alkylthioalkanoic acids or lower alkyl esters of such acids are useful as stabilizers of organic material normally susceptible to oxidative and/or thermal deterioration. The co-esters are advantageously prepared by transesterification of such esters with pentaerythritol. Preferred co-esters are (I) pentaerythritol tris[3,5-di-tert-butyl-4-hydroxyphenyl)propionate]-mono[3-n-dodecylthiopro pionate] and (II) pentaerythritol bis[-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]-bis[3-n-dodecylthiopro pionate]. The co-esters are especially useful in stabilizing applications for which physical mixtures of (i) (3-alkyl-4-hydroxyphenylalkanoic acid esters of polyols with (ii) polyalkanol esters of alkylthioalkanoic acids have heretofore been proposed.
由Pentaerythritol、(3-烷基-
4-羟基苯基)-
脂肪酸和烷基
硫代
脂肪酸或这些酸的低级烷基酯制成的Pentaerythritol共酯是有用的有机材料稳定剂,通常容易受到氧化和/或热降解的影响。这些共酯通过与Pentaerythritol的酯交换反应优势地制备而成。首选的共酯是(I) Pentaerythritol三[3,5-二(叔丁基)-
4-羟基苯基
丙酸酯]-单[3-正
十二烷硫代
丙酸酯]和(II) Pentaerythritol双[-(3,5-二(叔丁基)-
4-羟基苯基)
丙酸酯]-双[3-正
十二烷硫代
丙酸酯]。这些共酯在稳定应用中特别有用,之前已经提出了(i)聚醇的(3-烷基-
4-羟基苯基)
脂肪酸酯与(ii)烷基
硫代
脂肪酸的聚烷醇酯的物理混合物。