Effect of Solvent Type on Tannin Extractability from Three Tetrapleura Tetraptera (Schum. & Thonn.) Taubert Positions for Wood Composite Adhesive Formulation
Date
2012
Authors
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Journal ISSN
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Publisher
Journal of Emerging Trends in Engineering and Applied Sciences
Abstract
Raw materials for adhesive production are conventionally from expensive petrochemicals, which affect
synthetic resins relative to total costs of glued products. Phenol replacement with tannins (i.e., plant
polyphenols) in Phenol-Formaldehyde resins is imperative since tannin adhesives are equally resistant to
moisture and microbial degradation. Tannin was extracted from Tetrapleura tetraptera (i.e., bark, leaf and fruit)
using distilled water and 1% NaOH through Soxhlet extraction. Tannin presence, Extract yield and
polyphenol/tannin content (i.e., Stiasny numbers) were respectively determined from qualitative and
quantitative analyses. The solvent type and plant part influenced the yield and tannin content. All the three
parts, especially the bark, contained tannin. Extract yield was greater in 1% NaOH (39.54% [from leaf] to
77.05% [from fruit]) than in distilled water (12.96% [from fruit] to 18.16% [from leaf]). Conversely, Stiansy
numbers for tannin, at all plant parts, were greater for the water-soluble extracts (i.e., 67.50, 68.96 and 87.50%
from the leaf, fruit and bark respectively) than in 1% NaOH (i.e., 33.72, 21.94 and 37.42% correspondingly).
The large extract yields (i.e., 39.54 - 77.05% for 1% NaOH) and high Stiasny numbers particularly for the
water-soluble extracts (e.g. 87.50% for the bark) demonstrate the potential of T. tetraptera extracts as agents for
tanning and adhesive formulation for leather, wood and related industries.
Description
Article published in the Journal of Emerging Trends in Engineering and Applied Sciences (JETEAS, 2012
Keywords
extract yield, polyphenol, quantitative test, sodium hydroxide, soxhlet extractor, tannin adhesive
Citation
Journal of Emerging Trends in Engineering and Applied Sciences (JETEAS) 3(3): 517-525