Synthesis, Characterization and Utility of Novel Organic Antioxidants for Some Rubber formulations

Abstract

Acrylonitrile butadiene rubber (NBR) like all rubber materials suffers from deterioration which is generally occasioned by oxygen, ozone, heat, and dynamics stress. In addition, the sensitivity of unsaturated double bonds in butadiene units leads to decrease heat resistance of NBR. Several systems of antioxidants are used to improve the resistance of NBR against thermal-oxidative during storage and processing. Traditionally, the most common antioxidants are hindered phenols and aromatic amines. However, phenolic antioxidants were not commonly used in rubber matrix due to low efficiency caused by their quick volatile or migration from rubber matrix. The present work discusses evaluation the activity of the prepared novel amine antioxidants. This has been achieved by a study of their effects on physico-mechanical and electrical properties of NBR compared with the activity of a commercial antioxidant (TMQ) in the presence of different types of reinforcing fillers such as silica or carbon black (HAF).

• In this part, 2-propyl-1H-benzo[d]imidazole (3a) and 2-heptyl-1H-benzo[d]imidazole (3b) were successfully prepared through condensation reaction between o-phenylenediamine with n-butanoic (2a) and n-octanoic acid (2b), respectively.

• Their structures were confirmed through FT-IR, H1-NMR and identity of melting points with the literature.

• 2-alkylbenzimidazole derivatives (3a,b) were incorporated in acrylonitrile butadiene rubber (NBR) using silica filler as an insulator filler and carbon black (HAF) as conductive filler.