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This paper presents the results of a study investigating the biodegradation of poly(butylene
succinate) (PBS)/wheat bran (WB) biocomposites. Injection mouldings were subjected to biodegra-
dation in compost-filled bioreactors under controlled humidity and temperature conditions. The
effects of composting time (14, 42 and 70 days) and WB mass content (10%, 30% and 50% wt.)
on the structural and thermal properties of the samples were investigated. Measurements were
made by infrared spectral analysis, scanning electron microscopy, differential scanning calorimetry,
thermogravimetric analysis, and gel permeation chromatography. Results demonstrated that both
the thermal and structural properties of the samples depended greatly on the biodegradation time.
Specifically, their crystallinity degree increased significantly while molecular mass sharply decreased
with biodegradation time, whereas their thermal resistance only showed a slight increase. This
resulted from enzymatic hydrolysis that led to the breakdown of ester bonds in polymer chains. It
was also found that a higher WB content led to a higher mass loss in the biocomposite samples during
biodegradation and affected their post-biodegradation properties. A higher bran content increased
the degree of crystallinity of the biocomposite samples but reduced their thermal resistance and
molecular mass.
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