Análise comparativa da eficácia de isotiazolinonas como conservantes em produtos de estética automotiva

Abstract

The automotive detailing sector has shown significant growth in recent years, driven by the increasing appreciation of vehicle preservation and appearance, which has resulted in a higher demand for products that facilitate automotive care. In this context, the automotive detailing industry has invested in the development of increasingly efficient, safe, and stable formulations capable of meeting market demands as well as varied conditions of use and storage. Preservatives are essential to ensure microbiological safety and to contribute to the maintenance of the performance of automotive formulations, helping to guarantee product stability over the long term. However, the selection of these components must take into account factors such as regulatory compliance, potential risks to user health, and environmental impact. In view of this, the present study aimed to evaluate the physicochemical stability of automotive formulations containing two different preservative systems. For this purpose, three distinct products, designated A, B, and C, were selected and formulated with the preservatives chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT) and benzisothiazolinone (BIT). The samples were subjected to physicochemical tests, including analyses of pH, density, viscosity, and total solids content, as well as sensory evaluations in which color, odor, and appearance were assessed. In addition, accelerated stability tests were performed to evaluate the behavior of the samples under stress conditions, including centrifugation and heating tests. The results showed that viscosity was the parameter that exhibited the greatest variation throughout the tests, highlighting the influence of the preservative system on the rheological stability of the formulations. It was observed that the BIT preservative demonstrated superior performance in maintaining product viscosity when compared to the CMIT/MIT system. In the centrifugation test, product A exhibited phase separation, whereas in the heating test, product B began to show phase separation, indicating different sensitivities of the formulations to the evaluated stress conditions. It is concluded that the BIT preservative system contributed more effectively to the physicochemical stability of the formulations, particularly with respect to viscosity maintenance, reinforcing the importance of appropriate preservative selection in combination with the specific characteristics of each product in the development of stable and safe automotive formulations.