Synthesis of cellulose from Acetobacter xylinum bacteria – application of making biocomposite based on polyvinyl alcohol/cellulose

Abstract

Bacterial cellulose (BC) is characterized for its high purity, good mechanical strength, non-toxic and non-allergic. Therefore, BC was used in many applications, such as biological films, paper, textiles, electronics, and especially in the biomedical field. The aim of this study is to make a new material which has high thermal stability and mechanical strength by combining BC and two kinds of polyvinyl alcohol (PVA 127 and PVA Kuraray). In the current study, it was found that the structure of bacterial cellulose was changed when PVA at different concentrations was supplied in the bacterial culture. The dispersity of BC fibers and the density of PVA particles of the material increased with high concentration of PVA. As a masterbatch (a composite additive material), a preparation of BC/PVA 217 was mixed with PVA Kuraray, and the mixture was then placed into a mixing chamber of an electrically heated machine (Hakke, Germany) at 170C, 80 rpm for 15 min. The melting mixture was shaped by a Hydraulic shaping machine. The structure of the material was assessed by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). The thermal stability of the material was measured using a thermogravimetric analyzer, and its mechanical properties were also studied. The results showed that the compatibility of BC and PVA in PVA/BC material is relatively high due to intermolecular hydrogen bondings. The material showed better thermal stability than PVA only. Its mechanical properties were also improved. The finding suggests that the composites of bacterial cellulose and PVA could be good candidates for replacing traditional nonbiodegradable plastic materials.