Elongation at break of un-aged and aged blends before and after thermal ageing is illustrated in Fig. 3. The elongation at break is an indication of the elasticity or flexibility of the sample upon stretching till failure. Results clearly showed that an un-aged MBT-vulcanised blend provided superior elasticity over CBS, TBBS and TMTD-vulcanised blends, respectively. This finding is also verified by the tensile modulus and hardness results. Tensile modulus or hardness is directly related to the stiffness or rigidity of the blends. Here, it is confirmed that MBT-vulcanised blends provide the lowest stiffness and hardness in comparison to other accelerators type. The low tensile modulus or rigidity resulted in an increment of the deformability, delayed initiation of a crack in the rubber surface and subsequently, led to the elongation of the catastrophic failure. Furthermore, TMTD-vulcanised blends showed the greatest tensile modulus and hardness results. Apart from the rigidity or stiffness, tensile modulus or hardness is also an indication of crosslink density. It was noticed that even TMTD-vulcanised blends consisted of superior crosslinks but in terms of tensile strength, it was the opposite. This is associated to the restriction of chain segments. When the crosslink density is too high, the average molar mass of the rubber chain between two successive crosslink points decreases and the mobility of the chain segment is then restricted,limiting the orientation of the network chain. This would eventually reduce the number of effective network chains as a result of the decrease in tensile strength [17].