Investigation of structural, physical and thermal properties of bio-composite thin film from waste banana peel

Reinforcement and banana peel as matrix in the manufacturing of bio-composite thin film.
Banana peel fibers exhibit a good renewable material for the substitution of cement
based composite. However, the bio-composite properties are limited by the poor
adhesion between natural fiber interface and polymer matrix, which could be then
improved by chemical modifications on fibers. In this research, banana peels were
subjected to silane treatment. Bio-composite thin film manufacturing processes were
carried out with blending and hand lay-up technique with various concentrations of
eggshell filler which were EWE 0%, EWE 5% and EWE 10%. X-ray diffraction (XRD),
Fourier Transformation Infrared Spectroscopy (FTIR), Thermogravimetric Analysis
(TGA) and thickness swelling test were conducted on silane treated and untreated
banana peel bio-composite samples. In XRD analysis, it was found that EWE 10%
samples has the highest crystallinity compared to EWE 0% and EWE 5% and silane
treated samples achieved higher crystallinity than untreated samples. For FTIR test,
lignin component has been removed in silane treatment with the evidence of the
characteristic IR peak changed and new bonds (-Si-O-C-, –Si-O-Si- and -Si-C-) found in
silane treated samples. Besides, TGA results showed thermal stability of silane treated
samples was highly improved along with the increased of eggshell filler percentage with
the proof of decreased in decomposition stage. In thickness swelling test, the samples
achieved higher swelling percentage when the percentage of eggshell filler increased.
However, the decreases of 5-6% in thickness swelling of treated sample were possibly
offset by the enhancement in fiber/ matrix interfacial adhesion. In conclusion, silane
treatment can modified fiber’s surface and its structure, therefore silane treated samples
showed the increased in crystallinity, enhanced in its thermal stability and also reduced
in the water absorption. Besides, eggshell fillers helped to increase water absorption and
thickness swelling percentage on samples.