Fabrication, Characterization And Application Of Nanocellulose From Hemp Fibres

The increasing environmental awareness, growing global waste problems, and the global warming motivated governments around the world to increase the legislative pressure.Renewable resources from agricultural or forestry products form a basis for new industrial products or alternative energy sources. Natural-based fibres are used in a wide range of products such as textiles and geotextiles, special pulps and papers, reinforcement for polymers. As the development of nanotechnology, researchers pay much more attention on the fabrication of nanomaterials from natural fibres and their applications.In this present project (work), we focus on the extraction of nanocellulose from hemp fibres and the application of hemp nanocellulose for natural fibre modification and nanocomposite. We develop a novel method with couple outstanding advantages for the fabrication of nanocellulose. A central composite design (CCD) is applied using Design-Expert software to optimize the conditions of fabrication.The results show that the yield maximum amounts to more than 50% under the following conditions: time 4 h; temperature: 65 oC, dosage of swelling agent 4-4.18%; dosage of oxidant 60-62.29%. According to NTA (Nanoparticle Tracking Analysis), the mean size of nanocellulose can get around 100 nm. Characterized with AFM and FEG-SEM showsthat the dimension of nanocellulose is 3-dimensional system. ATR-FTIR shows that parts of the hydroxyl in C2, C3 and C6 are oxidized. But the oxidative reaction seems did not give rise to the decrease of CI. DSC determination shows that the thermal stability of nanocellulose is less then raw fibres.Dislocation also been investigated systematically by using ATR-FTIR and EDX during the second stage of research for the hemp fibres modification. Tensile testing shows that DTAB-Nanocellulose modification can increase the mechanical properties of hemp fibres significantly. FEG-SEM morphologies observation shows clearly that nanocellulose can modify the fibres by (1) filling in the interfibrillar gap or form thin film between fibrils and (2) filling in the stria on the surface of hemp fibres. XPS determination shows that nanocellulose may modify the fibres by aldol condensation. A higher CI can be got, when the pH Value is 11-12 and the dosage of DTAB is around 0.1%. XPS and ATR-FTIR are used to investigate the interfacial agehesion of polyester on the fibre. The interface between fibre and resin can be increased by the DTAB-Nanocellulose modification, this may be due to the esterifiable reaction. DETA is used to modify nanocellulose, and the results show that epoxy/nanocellulose nanocomposite can get a maximum of mechanical properties at the following condition: cure temperature 130 oC, dosage of nanocellulose 0.035%. Isothermal cure kinetics of epoxy/nanocellulose has also been investigated in present work. Three kinds of model are used to analysis the cure behavior of nanocomposite,...