Pemanfaatan zeolit sebagai bahan pengisi dalam pembuatan karet sponge untuk tatakan sepatu

The purpose of this research was to study the effect of zeolite as filler in the preparation of sponge rubber for shoe insocks. During wearing period of shoes, unpleasant odor often smell for the result of sweat accumulation and their decomposition by microorganism. Besides as rubber filler, zeolit has odor adsorption function. The formula of rbber sponge could be as the following : crepe rubber 100 phr, paraffinic oil 20 phr, ZnO 10 phr, stearic acid 5 phr, MBTS 1 phr, TMTD 0.25 phr, anti-oxidant 1 phr and sulphur 2 phr. To obtain the best sponge rubber formula, some experiment was done by formulating variation of zeolite and blowing agent AZDM in the amount of 25, 50, 75 phr and 5, 10, 15 phr respectively. The vulcanization process was carried-out at temperature 140oC for minutes by compression moulding. The research showed that the best formula with high odor absorption was consist of zeolite 50 phr and blowing agent AZDM 5 phr. The sponge rubber had odor adsorption 93,47%, and the physical properties were as follow: tensile strength 2.018 N/mm2, elongation at break 251%, tear strength 1.029 N/mm2, density 0.717 g/cm3, and compression set 36.38%. Odor absorption was tested by using gas chromatography.