Investigating the Performance of Emulsion Paint Formulated with Brachystegia eurycoma and Brachystegia nigerica Powders as Thickeners.

Abstract

The search for eco-friendly and sustainable materials in paint formulation has led to increased interest in natural thickeners derived from renewable plant sources. This study investigates the potential of Brachystegia eurycoma and Brachystegia nigerica seed gums as natural thickeners in the development of emulsion paints. The natural gums, processed to a particle size of 75 µm, were incorporated into water-based paint formulations at different concentrations and compared with a control sample containing a commercial thickener (Bermacol). The formulated paints were evaluated for key physico-chemical properties including viscosity, pH, specific gravity, drying time, settling resistance, and sagging resistance using standard test procedures in accordance with the Nigerian Industrial Standards (NIS). Results showed that the viscosities of the Brachystegia-based paints ranged between 8.20 p and 18.50 p, while the control exhibited a higher viscosity of 52.41 p. All samples maintained pH values within the acceptable range (7.22–8.22), ensuring chemical stability and suitability for architectural applications. The specific gravity values (57.40–77.91) were slightly lower than the industrial sample (95.08), indicating lighter paint formulations with good coverage properties. Drying times ranged from 25 to 42 minutes, which are well within the standard limit of 24 hours, while settling resistance improved significantly with increasing thickener concentration sample G showed no observable sedimentation. Sagging resistance tests also confirmed enhanced film stability and reduced dripping for higher Brachystegia concentrations.The findings reveal that Brachystegia eurycoma and Brachystegia nigerica possess strong thickening, stabilizing, and rheological-modifying properties suitable for water-based paint production. Their use as natural thickeners offers a promising, cost-effective, and environmentally friendly alternative to petroleum-derived industrial thickeners. This study, therefore, establishes a foundation for the large-scale utilization of local plant-based biopolymers in sustainable paint manufacturing.