Nano cellulose Nanotechnology is a strongly increasing area of research, training and development, and one that holds great promise for sustainable applications. Cellulose is a material widespread in nature and it may be obtained from many natural sources such as wood, cotton, and vegetable biomass. Cellulose is the most abundant and renewable natural resource on earth. Suitable prepared cellulose in the form of powder (nanocellulose or microfiberillated cellulose) is very useful products. They have been applied in pharmaceutical, food, ceramics, paint, textile and many other industries. Such a wide application is attributed to their special properties: nano dimensional particle size, large specific areas, and internees to many organic or inorganic substances. Nano- cellulose derived from natural sources is classified as nano-products. Both the bottom-up and top-down applicable to the production of nano-cellulose. Nano-cellulose can also be obtained from native fibers by an acid hydrolysis, giving rise to highly crystalline and rigid nanoparticles (generally referred to as nanowhiskers) which are shorter (100s to 1000 nanometers) than the nanofibrils obtained through the homogenization route. The resulting material is known as nano-crystalline cellulose (NCC). Typical lateral dimensions are 5-20 nanometers and longitudinal dimension is in a wide range from tens of nanometers to several micrometers. It is pseudo-plastic and exhibits the property of certain gels or fluids that are thick (viscous) under normal conditions, but flow (become thin, less viscous) over time when shaken, agitated, or otherwise stressed. This property is known as thixotropy. Cellulosic materials intended for use as nano-fillers in composites are usually subjected to hydrolysis by strong acids such as sulfuric or hydrochloric acid, which causes a selective degradation of amorphous regions of cellulose and, consequently, the splitting of micro-fibril beams. As a result of cellulose hydrolysis, the disintegration of its hierarchical structure takes place to form crystalline nanofibers or nanocrystals, usually referred to in literature as nanowhiskers. The morphology of the nanocrystals obtained depends on the source of cellulose and hydrolysis conditions used, such as acid concentration, the ratio of acid to cellulose, temperature and reaction time.
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