Effect of silica reinforcing agent treated with admicellar polymerization technique on the mechanical properties and ozone resistance of natural rubber

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Thamchoto Prajaksood
Bhuriphat Saenpong


This article investigated the effect of adding admicellar polymerized silica (modified silica) as a reinforcement filler on mechanical properties and ozone resistance of natural rubber. In this study, the modified silica was added to 300 grams natural rubber with different ratio ranging from 20 to 50 phr (Parts Per Hundred of Rubber). The reinforced rubber specimens were formed by compression molding at a 145 °C. Later, the specimen were undergone mechanical tests and the ozone resistant test to obtain tensile strength, tear strength, hardness, and ozone aging resistance. The results revealed that the reinforced rubber with 40 phr modified silica that was cured for 138.23 ± 1.06 s exhibited  the best mechanical properties and ozone aging resistance. The tensile strength, the 300% modulus, the tear strength, the elongation at break, and the Shore A hardness of the 40 phr specimen were 21.55 ± 0.40 MPa, 4.62 ± 0.17 MPa, 73.67 ± 1.58 MPa, 579.96 ± 6.70%, and 55.33 ± 1.15, respectively.

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บทความวิจัย (Research Article)


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