星形受阻酚抗氧剂的抗氧化性能研究

Oxidation Resistance of a Star Type Hindered Phenolic Antioxidant

利用星形聚合物的端基可以进行功能基转化这一特殊性能,将具有抗氧化性能的化合物-β(3,5-二叔丁基-4-羟基苯基)丙酰氯引入到以氨为核的低代聚酰胺-胺(PAMAM)星形高分子上,合成了一种星形受阻酚抗氧剂。研究了该星形抗氧剂对线形低密度聚乙烯(PE-LLD)和聚丙烯(PP)的抗氧化作用。结果表明,该抗氧剂在2种聚烯烃材料中均具有良好的加工性能和抗氧化性能,在PE-LLD中的氧化诱导期为市售抗氧剂1010的1.3倍、抗氧剂3114的1.4倍,在PP中的抗氧化性能与这2种抗氧剂相当;添加该星形抗氧剂可使PE-LLD的拉伸强度和断裂伸长率分别从12.6 MPa和652%升高到17.9 MPa和696%,使PP的拉伸强度和断裂伸长率分别从36.9 MPa和182%升高到40.0 MPa和248%;经25 min塑炼后,添加该星形抗氧剂的PE-LLD和PP的熔体流动速率变化很小。

A kind of star type hindered phenolic antioxidant was synthesized by introducing β-（3,5- di-tert-butyl-4-hydroxyphenyl） propionyl chloride into poly （amidoamine）（PAMAM） as end groups. The oxidation resistance of the star antioxidant in PE-LLD and PP was studied. It showed that it had excellent processing ability and oxidation resistance behavior in polyolefin resin. Applying to PE, the oxidation induction time （OIT） was 1.3 times that of antioxidant 1010 and was 1.4 times that of antioxidant 3114. Applying to PP, the oxidation resistance was equal to that of antioxidant 1010 or 3114. The tensile strength of PE-LLD increased from 12. 6 MPa to 17. 9 MPa and the elongation at break increased from 652 % to 696 % with the addition of the star type antioxidant. The tensile strength of PP increased from 36.9 MPa to 40. 0 MPa and the elongation at break increased from 182 % to 248 % with the addition of the star type antioxidant. After 25 rain mastication, the melt flow rate of PE-LLD and PP with the star type an（ioxidants changed insignificantly.