Análise térmica aplicada ao estudo das reações de vulcanização em elastômeros: efeito de óleos vegetais e da cera de abelha

Abstract

The vegetable oils of peanut, linseed and coconut, plus beeswax, were evaluated as activators of the vulcanization process of elastomers by thermal analysis - thermogravimetry (TG) and differential scanning calorimetry (DSC). Through of TG analysis, experimental data indicated a second order mechanism for thermal degradation kinetic and a relative stability thermal according to: stearic acid < beeswax < coconut oil < linseed oil < peanut oil. Furthermore, by DSC, interactions between conventional ingredients of the elastomeric compounding (zinc oxide, ZnO; sulfur, S; stearic acid, CH3(CH2)16COOH; and, an organic accelerator of the sulfenamide type) and vegetable oils or beeswax revealed that vegetable oils, such as peanut and linseed, exhibit similar behavior to stearic acid but may be a possible substitute in the formulation. Moreover, for an effective confirmation of the hypotheses, in the case of coconut oil and beeswax a further investigation must be done.