Formulation of a novel bio-resin from banana sap

► A novel bio-resin was synthesised using banana sap derived from the psuedostem of the banana plant. ► The banana sap was characterised by chemical and physical methods. ► We have shown that by adding banana sap to the polypropylene resin the mechanical properties of the resultant resin were improved. ► The new resin was characterised by FTIR, TG, DSC and DMA. The purpose of this work is to develop and characterise a novel bio-resin made from banana sap (BS) for low end applications such as the interior components of motor vehicles. The sap from banana plant (Musa cavendish), that is locally grown in Kwa-Zulu Natal, South Africa, was used as the starting material for the bio-resin. The BS was characterised using various physical and chemical testing methods. Qualitative analysis of BS confirmed the presence of carbohydrates which was quantified by high performance liquid chromatography. Phenols were identified by gas chromatography–mass spectrometry. BS from the pseudo stem of the plant was added in varying concentrations (30–65wt.%) to polyester resin. The bio-resin was processed for 12–35h and reacted with styrene, an initiator and a catalyst, and cured at room temperature for 24h and post cured at 80°C for 3h. The thermal and mechanical properties of the resulting product, called a banana sap maleate were evaluated by differential scanning calorimetry, thermogravimetry and dynamic mechanical analysis. It was concluded that adding 50wt.% BS gave the best mechanical properties when compared to the control resin which is 100% petroleum-based unsaturated polyester resin.