Surface modification of maize stem with polydopamine and tannic acid coatings

Abstract

The paper presents the results of research on the modification of maize stem. The modification consisted in depositing polydopamine or tannic acid coatings on the surface of the stems. The coatings were deposited from solutions without and with an oxidant (potassium permanganate) with different deposition times. The deposition effects were assessed by measuring the mass of the samples, optical microscopy and scanning electron microscopy. The thermal stability of the modified maize stem was also determined and differential scanning calorimetry tests were carried out. Studies have shown that as a result of the deposition, a coating of polydopamine or tannic acid was formed on the surface of the maize stem, and the quantity of coating increased with increasing deposition time. The oxidant used was only effective for the polydopamine coating, greatly increasing the deposition rate. The thermal stability of the coatings deposited on the maize stem is sufficient for the modified filler to be used in the processing of biodegradable polymers. The modified maize stem is planned to be used as filler for biodegradable polymers hopefully increasing adhesion strength between matrix and filler and improving the mechanical properties of the resulting composites.