A Study of Aging Properties of Uncured NR/BR Blends: Using TG-DTG Technique

The changes in mechanical, rheological and thermal properties of NR/BR blends (60/40) after aging at different period of time were investigated. The prepared rubber blends were conditioned at a temperature of 23±2 ?C for up to 140 h in an aging box. The TG-DTG curves demonstrated two significant factors, ?Tmax (differences between maximum peak temperature of BR blend aged for 140 h with maximum peak temperature of BR blends aged for 27, 51, 75, 99 and 123 h) and peak height ratio (hNR/hBR). The correlation between rheological (TS2, TC90), mechanical (strain, modulus 100% and modulus 300%), and thermal parameters (?Tmax, hNR/hBR) with aging time of NR/BR blends were studied. Parameters such as TC90, modulus 100%, modulus 300% and hNR/hBR showed a correlation with time of aging. Whereas, no significant correlation between TS2, strain and ?Tmax were found as the time of aging increased.