Autor(es): Mohammadkazemi, F. ; Aguiar, R. ; Cordeiro, N.
Data: 2017
Identificador Persistente: http://hdl.handle.net/10400.13/3318
Origem: DigitUMa - Repositório da Universidade da Madeira
Assunto(s): Bacterial nanocellulose; Bagasse fiber; Green composites; Inverse gas chromatography (IGC); Fiber–cement composites; .; Faculdade de Ciências Exatas e da Engenharia
The design of green fiber-reinforced nanocomposites with enhanced properties and dura bility has attracted attention from scientists. The present study aims to investigate the potential of bacterial nanocellulose (BNC) as a green additive for fiber–cement composites. Inverse gas chromatography (IGC) was used to evaluate the influence of incorpo ration of BNC as powder or gel, or coated onto the bagasse fibers, on the fiber–cement composite (FCC) surface. The results indicated that BNC incorporation made the FCC surface more reactive, increasing the dispersive component of the surface energy. The most relevant effects were found for BNC incorporation as gel or coated on the fibers. Incorporation of BNC as gel resulted in a predominantly organic FCC surface with substantial decreased surface basicity (Ka/Kb ratio from 2.88 to 5.75). IGC also showed that FCC with BNC incorporated as gel was more susceptible to hydration. However, BNC coated on fibers prevented fiber mineralization, increasing the inorganic materi als at the surface, which caused an increase in the surface basicity (Ka/Kb ratio decrease to 2.00). These promising results could contribute to development of a new generation of green hybrid composites. The IGC technique enabled understanding of the physicochem ical changes that occur on deliberate introduction of nanosized bacterial cellulose into fiber–cement composites.
