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Polybutadienes are prone to oxidation due to unsaturation in its structure. In order to prevent oxidation, antioxidants are usually added to Polybutadiene. Antioxidants break the degradation chain by donating H-atoms to free-radicals, thus preventing those radicals from propagating the chain reaction. The antioxidants are usually hindered phenol and aromatic amines. The most common hindered phenols are 2,6-di-tert-butyl-4-methylphenol (BHT) and 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol (AO 2246) or also called (CALCO 2246). Hydroxyl terminated polybutadiene was prepared by free radical polymerization of 1,3-butadiene using H 2 O 2 as initiator. It was characterized for number average molecular weight, hydroxyl value, residual peroxide, moisture contents, polydispersity and microstructure. Two different antioxidants BHT and AO 2246 were separately added to this HTPB for stabilization against oxidation. The antioxidant activity of these two antioxidants was compared in polybutadiene hydroxyl terminated by measuring their oxidation induction temperature using DSC. The results indicate that oxidation induction temperatures obtained with AO2246 are higher as compared to those obtained with BHT which indicates a higher antioxidant activity of AO 2246. The results show that 0.1% AO 2246 is providing stabilization equal to 0.5% BHT. Accelerated aging indicate that AO2246 is providing more high temperature stabilization to polybutadiene hydroxyl terminated as compared to BHT. BHT being more volatile in nature exhibited faster depletion rate as compared to AO2246. AO2246 is a large molecule with less mobility, high melting point and boiling point, therefore, it stays more in the matrix, provides long term protection against oxidation and increases shelf life of polybutadiene hydroxyl terminated.