An Analysis on Various Properties and Durability of Natural Rubber |
The focus of this research was to investigate the effectof thermal degradation upon the mechanical properties of natural rubbercompounds and apply those effects to the life prediction of off axis 2-ply cordrubber laminates. The work examined both the quasi-static and dynamicmechanical properties of two natural rubber vulcanizates, which had beensubjected to isothermal anaerobic aging. Thermal aging was performed on two different naturalrubber vulcanizates. The thermal aging was conducted between the temperaturesof 80 and 120°C for times ranging from 3 to 24 days. The effect of thermaldegradation was measured from the changes in the chemical composition of thevulcanizates as functions of time at temperature. A master curve relationshipbetween the changes in the chemical composition of the vulcanizates due tothermal degradation and their static and dynamic mechanical properties has beendeveloped. This relationship allowed for the prediction of the vulcanizatemechanical properties after thermal aging. It was found that the mechanicalproperties correlated with the percentage of poly and monosulfidic crosslinks,where in general higher levels of polysulfidic crosslink gave rise to thehighest mechanical properties.