Paper Title
Study the Effect of Calcium Carbonate from Eggshell as a Filler in Natural Rubber

Abstract
This work investigated the potential to use calcium carbonate from eggshell as a filler in natural rubber for cost reduction and get rid of solid waste of eggshell. In order to increase the interaction of filler and natural rubber, the eggshell is coated by using lard and palm oil. The amount of eggshell is varied from 0 to 40 phr. The rubber compound was prepared by using internal mixer and two-roll mill. The mechanical properties were studied by using tensile testing. The results showed that the scorch time and cure time did not change by adding calcium carbonate from eggshell. The hardness and tensile strength of vulcanizate were increased when adding filler. The hardness, modulus and tensile strength of vulcanizate were higher when increased the amount of filler. Then, calcium carbonate from eggshell can be used as a filler in the natural rubber composite. The amount of eggshell can be used up to 40 phr in natural rubber composite. Index Terms —Calcium carbonate from eggshell, Palm oil, Lard, Natural rubber.