Evaluation of the Suitability of Oil Palm Fruit Bunch Stalk Fibre for Lagging of Hot Food Containers

Abstract

Oil palm fruit bunch stalk fibres obtained after the harvest from a plantation located at Offa, Nigeria. These fibers were treated
with 5% NaOH aqueous solution, used to reinforce polypropylene polymer and investigated for thermal insulation of hot food
carrying flasks. Treated fibres were loaded in concentrations by weights of 10%, 20%, 30% and 40% as filler into polypropylene
matrix, fabricated into composites with an injection moulding machine with specimen of each formulation analysed for chemical,
physical, mechanical and thermal properties including density, hardness, impact/tensile strengths, thermo-gravimetric and thermal conductivity using standard test equipment to ascertain the suitability for heat resisting application. Test equipment
included Lee’s disc apparatus, Perkin Elmer instrument, Instron tensile, Tinius impact and Rockwell hardness testers accessed in
workshops and laboratories in Nigeria. The characterization result showed the composite as nontoxic to humans if it contacted
food in the flask. The physical, mechanical and thermal properties showed that only 20%-40% fibre loading was beneficial after
which performance declined. Mechanical properties of bunch stalk reinforced composites (density, hardness, impact and tensile
strength) were adequate for the service conditions. The decomposition temperature of composites was about 4800C which was
above 3500C-4350C for most conventional domestic insulators, 2810C for pure treated bunch stalk fibre and 4350C for polypropylene matrix. Thermal conductivity reduced from 0.11- 0.23Wm-1K-1for polypropylene matrix to 0.0025Wm-1K-1 for
40% 10mm thick fibre loaded composite while it was 0.066Wm-1K-1 for 50mm thick rock wool, 0.036Wm-1K-1 for glass fibre and
0.03Wm-1K-1 for polystyrene used as conventional domestic insulators. This confirmed superiority of the fruit bunch stalk
reinforced composites as for thermal insulation application over common domestic insulators