Comparison of Characteristics of Natural Rubber Compounds with Various Fillers

Natural rubber is the most frequently used elastomer worldwide due to its low prices, renewability, non-toxicity and excellent physical properties. Natural rubber is not used as such but in the form of mixtures which generally contain: fillers for reinforcement, plasticizers, crosslinking agents and other ingredients that confer different characteristics to the final product. Reinforcement of elastomers by incorporating fillers is a process of great practical and technological importance that greatly enhances the physical-mechanical properties of the composite material and reduces the cost price. The origin of such mechanical reinforcement has been linked to the interaction between the rubber and filler as well as the homogeneous dispersion of the filler within the polymer matrix. In natural rubber technology, knowledge of the conditions necessary to achieve more efficient natural rubber–filler interactions is improving continuously. The purpose of this article is to determine the influence of different types of mineral or organic fillers on the properties of natural rubber mixtures. The following were determined for the mixtures obtained: curing characteristics, hardness, elasticity, tensile strength, elongation at break and tear strength. The results indicate that both organic and inorganic fillers have led to improved physical and mechanical characteristics.