Potential application of resin extracts of <i>Anogeissus leiocarpus</i> plant

Abstract

This work reports the application of tannin obtained from Anogeissus leiocarpus plant and its use in formulation of a thermosetting material for domestic and industrial use. The ploy condensation of tannin with formaldehyde produced a thermosetting resin with useful properties; formaldehyde (10.5 ml), tannin (2.5 g), glycerol (0.6 ml), hexamine (5.5 g), pH 7.5 and temperature 60 °C. Gel viscosity and effect of temperature on gel time were determined. Absorption behaviour of the films from the thermosetting material formulated under aqueous, acid and basic conditions were investigated. Water absorption up to 90% was obtained between 1 to 3 hrs. Perhaps due to differences in chain topology of the material formulated related to the molecular size holes in the polymer structure which depends on the morphology and crosslink density of the material. No acid absorption was observed after 12 hrs indicating that cross-linking reaction was still taking place in the solution.

Keywords: Thermosetting, Resin, Polycondensation, Tannin, polymerization, viscosity