Formulation, characterization, performance and durability of cool paints

• Grant number: 09/18246-0
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2010
• End date: April 30, 2013
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Principal Investigator: Kai Loh
• Grantee: Kai Loh
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The proposed project aims to continue a study initiated in Paula Ikematsu's dissertation. In this project, a methodology was developed to investigate the thermal performance of "cool" paints applied on fibre cement roof sheets. The results showed that these paints have potential to reduce the surface temperature of this type of roof sheet and to improve thermal comfort inside buildings constructed with this component. The study was performed with paints formulated and produced by a manufacturer, a partner in this project, so it was not possible to obtain the formulas of the samples neither the raw materials used. The present project aims to produce samples in laboratory using pigments and fillers selected according to their reflectance. The morphology, chemical and mineralogical composition of the pigments and fillers will be characterized using the following techniques: scanning electron microscopy (SEM), X-ray fluorescence spectrometry (XRF), X-ray diffraction spectrometry (XRD), Fourier Transform infrared spectroscopy (FT-IR). The appearance, colour, gloss, morphology, chemical and mineralogical composition of the films, obtained with the paint samples, will be analysed. The performance of the paints, produced in laboratory and acquired from the market, will be evaluated according to Brazilian standards and the results correlated. The durability and maintenance of the reflective properties of the paints will be studied by outdoor exposure of painted and unpainted fibre cement specimens, in sites located in urban, rural and marine environment. The properties: colour, gloss, reflectance after exposure will be evaluated and compared to values initially obtained before the exposure and the results correlated with data obtained from different natural exposures. (AU)