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Eggshells: A novel bio-filler for intumescent flame-retardant coatings
Progress in Organic Coatings (2015)

The aim of this study was to develop intumescent flame-retardant coatings that incorporate chicken eggshell (CES) waste as a novel eco-friendly bio-filler. Three flame-retardant additives, namely, ammonium polyphosphate phase II, pentaerythritol and melamine were mixed with flame-retardant fillers and acrylic binder to synthesize the intumescent coatings. The fire performance of the coatings was evaluated in accordance with 'BS 476: Part 6-Fire Propagation' and 'BS 476: Part 7-Surface Spread of Flame' test standards. It was found that 4 out of 5 of the coated specimens (B, C, D and E) neither showed surface spread of flame nor any afterglow combustion upon fire exposure. The addition of 5.0 wt% and 2.5 wt% eggshell bio-filler into formulations B and E, respectively, improved fire protection due to char formation, with better morphology, height and structure of the protecting shield. The filler compositions of samples D (3.4 wt% TiO2/3.3 wt% Al(OH)3/3.3 wt% Mg(OH)(2)) and E (2.5 wt% TiO2/2.5 wt% Al(OH)(3)/2.5 wt% Mg(OH)(2)/2.5 wt% CES) applied at a thickness of 1.5 +/- 0.2 mm achieved the lowest fire propagation index with a value of 4.5 and 5.0, respectively (BS 476 Part 6, Class 0 materials) which indicates excellent fire-stopping properties. The results showed that the coatings were effective in fire protection, with good qualities of water resistance, thermal stability, and adhesion strength. Significantly, coating E (with CES) has proved to be efficient in the protection of plywood against fire. (C) 2015 Elsevier B.V. All rights reserved. Link to Full-Text Articles :

  • acrylic resin,
  • chicken eggshell,
  • bio-filler,
  • eco-friendly,
  • intumescent coating,
  • flame-retardant,
  • fire protective-coatings,
  • vinyl acetate copolymer,
  • expandable graphite,
  • polypropylene composites,
  • mechanical-properties,
  • magnesium-hydroxide,
  • performance,
  • resistance,
  • steel,
  • polyethylene
Publication Date
April, 2015
Publisher Statement
Cd2st Times Cited:0 Cited References Count:50
Citation Information
"Eggshells: A novel bio-filler for intumescent flame-retardant coatings" Progress in Organic Coatings Vol. 81 (2015)
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