(英)硫代二甘醇二月桂酸酯的合成及其在聚丙烯中抗氧化性能研究

以硫代二甘醇和月桂酸为原料,选用对甲苯磺酸为催化剂,二甲苯为带水剂,合成了抗氧剂硫代二甘醇二月桂酸酯。适宜工艺条件为：反应温度140℃，醇酸摩尔比为2∶1.5，催化剂用量为月桂酸质量的2.0%。将产物应用于聚丙烯中,与商品化的抗氧化剂相比具有良好的抗氧化性能。结果表明，添加硫代二甘醇二月桂酸酯后，聚丙烯的熔体流动速率从5.36 g?10min-1 降低到 3.59 g?10min-1；断裂伸长率和冲击强度分别达到112.2 % 和 121.0 kJ?m-2。当与商品化抗氧化剂168或1010混合使用时，抗氧化性能显著增加：与168混合时，熔体流动速度、拉伸强度、断裂伸长率和冲击强度分别达3.28 g?10min-1 、40.2 MPa、140.8 %和124.2 kJ?m -2；与1010混合时，熔体流动速度达3.56 g?10min-1。

Preparation of dilauric acid thiodiglycol ester and evaluation of its antioxidant capacity in polypropylene resin

A new antioxidant dilauric acid thiodiglycol ester is prepared in high yield starting from thiodiglycol and lauric acid catalyzed by p-toluenesulfonic acid using xylene to remove water azeotropically with reaction temperature at 140 °C, molar ratio of thiodiglyol to lauric acid at 2:1.5, and loading of catalyst at 2 % by weight of lauric acid as optimized reaction conditions. The antioxidant activity of the product is investigated and compared with other commercially available antioxidants. The results show that when dilauric acid thiodiglycol ester is used as antioxidant additive, the melt flow index (MFI) of polypropylene powder decreases sharply from 5.36 g?10min-1 to 3.59 g?10min-1 and elongation at break and impact strength also reach a high level to 112.2 % and 121.0 kJ?m-2. The blending of dilauric acid thiodiglycol ester with commercially available antioxidant 1010 or 168 can further improve the antioxidant performance. Tensile strength of 40.2 MPa, elongation at break of 140.8 % and impact strength of 124.2 kJ?m-2 are obtained when dilauric acid thiodilglycol ester is combined with 168, while MFI decreases to 3.56 g?10min-1 and 3.28 g?10min-1 when it is combined with 1010 and 168, respectively.