Development of plant based adhesive for bottling applications

Abstract

Adhesives are utilized in various industries such as packaging, labelling, woodworking and pharmaceuticals. However, most of the used adhesives are obtained from petroleum-based sources such as polyvinyl acetate, urea-formaldehyde, and phenol-formaldehyde resins which are non-biodegradable; pose environmental pollution and health risk. Therefore, the study focuses on developing an ecofriendly, sustainable adhesive from Euphorbia tirucalli latex and banana corm gelatine which readily available in Uganda. Euphorbia tirucalli latex was extracted using ethyl acetate and stabilized using ammonia. Gelatine was extracted from the banana corms using citric acid pretreatment and ethanol precipitation Euphorbia tirucalli latex was characterized in terms of pH, density, total solid content, moisture content, and functional groups through FTIR analysis. A central composite design (CCD) was used to optimize latex concentration (10-40%w/v), gelatine content (5-35%w/v), and mixing time (15-55minutes) aiming to obtain bonding strength and viscosity as key response variable .The optimal formulation 40% latex and 20% gelatine with 40minutes mixing time giving a bonding strength of 2.29MPa and viscosity of 575.1 Cp with a drying time of 20.33 seconds, a which corresponds the range of industrial labelling adhesives. The adhesive showed good thermal stability up to 80℃, and its economic analysis showed that one litre could be produced at 16440shs using local material. Compared to synthetic adhesives, the plant-based adhesive showed peel strength of 2.29Mpa, clean removability from glass surfaces, and a reduced environmental footprint due to its biodegradability and low Volatile organic content emissions. The study confirms the feasibility of producing sustainable adhesives from agricultural waste and natural latex, aligning with Uganda’s green industrialization goals and the UN Sustainable Development Goals