Synthetic rubber is used in automobiles for various applications. Tires, seals, gaskets, engine mounts, wiring cables and under the hood hoses are just a few examples. Synthetic rubber is a man-made material that uses several components as polymers, resins, carbon black, fillers, vulcanizing agents, reinforcement agents. It is a material that heavily depends on oil for its constituency, therefore it has a large carbon footprint. This study proposes the use of natural filler for automotive seals using synthetic rubber in order to reduce the impact on the environment.
Calcium carbonate is the most preponderant choice as material filler because it is abundant in nature and is mined extensively. Calcium carbonate is also present in several structures in nature. Oyster shells have a great amount of it as well as egg shells.
Egg shells also constitute an environmental bio-hazard when discarded in a landfill due to the organic inner membrane. The use of discarded egg shells is limited to few applications, mainly pharmaceutical.
The following study analyzes the possible use of egg shell by-products from the food industry as filler for synthetic rubber used in automotive seals. The study presents test lab results of synthetic rubber recipes using ground egg shells, technical requirement of ground egg shells to meet rubber mixing specifications, a food industry analysis of the egg shell by-product volume, a feasibility analysis in order to sustain the mixing production of synthetic rubber for automotive seals and a cost comparison with current mined calcium carbonate.