Characterization of mechanical properties of marble sludge/ natural rubber composites

This study aims to investigate the possible utilization of marble sludge (ms) in natural rubber (nr) composites,which would reduce both the environmental pollution and product cost. marble waste in the form of sludge is taken from mangopir marble industrial area karachi. the sludge was dried,grinded and passed through desire sieves (20,37 and 75μm) and incorporated in the formulation of nr composites. the physical characteristics of dry ms were carried out in order to identify all components by instrumental techniques. different micro sized particles of ms (20,37 and 75μm) were added with different loading (10,30,50,70 and 90 phr). mechanical properties of ms filled nr composites were studied. it was found that tensile strength and tear strength increased with increasing the ms till 70 phr. further addition of ms in the composites decreased both strengths. elongation at break and rebound resilience decreased with increasing ms loading,while modulus,(100%,200% and 300% elongation),hardness,compression set and abrasion loss increased with increase loading of ms. all mechanical properties of smaller micro size ms particle (20 μm) filled nr composites have higher values then 37 and 75μm micro size particle. the results of mechanical properties after aging show that the tensile strength,modulus,elongation at break and rebound resilience values decreased while hardness,compression set and abrasion loss values increased.