Production process and evaluation of performance requirements of soil pigments based paint for buildings

Abstract The soil pigments are a sustainable alternative for the production of a paint to use on buildings. In this study production processes for soil pigment based paints were developed, aimed at obtaining a homogeneous and stable suspension, as well as evaluating the paints performance according to the norms established by ABNT NBR 15079:2011. Three samples of soil pigments extracted in the city of Viçosa, MG, were used. The formulations were defined using the statistic experimental mixture design. The performance of the mixtures was evaluated according to the limits of performance requirements established by ABNT. Both viscosity and the pH were measured and related to the performance. The results indicated that none of the formulations met all the performance requirements simultaneously. The pH had strong influence on performance, having defined viscosity, abrasion resistance, and the dry/wet paint hiding power. The mechanical dispersion, the "PVOH" resin and the pigments morphology determined the results obtained in this study, having become key themes to be addressed by other projects.

摘要 土壤颜料（soil pigments）是一种可持续的建筑涂料生产原料。本研究开发了基于土壤颜料的涂料制备工艺，旨在获得均匀稳定的悬浮液，并依据ABNT（巴西国家标准协会）制定的NBR 15079:2011标准评估涂料性能。研究使用了采自巴西米纳斯吉拉斯州维索萨市的3份土壤颜料样品。采用统计实验混料设计确定涂料配方。依照ABNT设定的性能要求限值对混合料的性能进行评估。测定了涂料的黏度与pH值，并分析二者与性能的相关性。结果显示，所有配方均无法同时满足全部性能要求。pH值对涂料性能影响显著，可决定涂料黏度、耐磨性以及干/湿态遮盖力。机械分散工艺、PVOH树脂（聚乙烯醇树脂）及颜料形貌是本研究结果的关键影响因素，相关内容可作为后续研究的重点攻关方向。