Effect Of Rigid Linker On Property Of Hindered Phenol Antioxidants

In this thesis, 3,5-di-tert-butyl-4-hydroxylbenzyl methyl ether, intermediate of antioxidant 1330, was synthesized with 2,6-di-tert-butylphenol and paraformaldehyde as raw materials, with dimethylamine as catalyst and with methanol as solvent. Then the intermediate react with l,3,5-trimethylbenzene to prepare antioxidant 1330 with H2SO4 as catalyst. The molecular structure of antioxidant 1330 and the intermediate have been characterized by means of FT-IR, 1H-NMR, the result indicates the correctness of the product structure.The antioxidant properties of different linkers of antioxidant 1024, antioxidant 1330,antioxidant 3114, antioxidant 1010 were evaluated by DPPH· scavenging ability, MFR,mechanical properties and OIT, antioxidant properties of four antioxidants were investigated from the stability of free radicals and polymer materials. The analysis of the scavenging DPPH· kinetics of them were carried out eventually, reaction rate of antioxidant 1024,antioxidant 1330 and antioxidant 1010 were slower compared to antioxidant 3114, for about25 min the reaction has ended, and in the four kinds of antioxidants, containing rigid linkers of antioxidants 1330 and antioxidant 3114 worst free radical scavenging capacity, the total number of stoichiometric was less than the theoretical number of stoichiometric, indicate that the rigid linkers reduced the free radical scavenging capacity of antioxidants. Study on Four kinds of antioxidants on the thermal stability of HDPE have shown that the thermal stability of containing rigid linkers of antioxidants 1330 and antioxidant 3114 were better than antioxidant 1010 that consumed the fastest under conditions of high oxygen pressure accelerated aging in water. In practical applications, the presence of an antioxidant molecule rigid linker which greatly improved the thermal stability, reduced the physical loss, exhibited better antioxidant properties.