Natural fibres ramie

The starting point in the textile supply chain is the raw material preparation. Textile fibres are obtained from two main sources natural (cellulose or animal) fibres or synthetic fibres. Natural cellulosic fibres include conventional and organic cottons, rayon, linen, hemp, jute, ramie and sisal. Cotton is used to produce 40% of world textile products (Saicheua et al., 2012). The major environmental concern in cellulosic fibre production, especially for cotton fibre, is the chemical fertilizers and pesticides used during cultivation. The second concern is the high level of water consumption (Dave and Aspegren, 2010 Muthu, 2014). Cotton is one of the most popular natural fibres used in the world. Three percent of the world s cultivated land is used for cotton production and 16% of the world s insecticides are used on this crop alone (Saicheua et al., 2012 Muthu, 2014). Moreover, the use of chemical fertilizers, pesticides, machinery and electricity causes some human health and environmental problems. Also cotton growing requires 7—29 tonnes of water per kg of raw cotton fibres (KaUiala and Nousiainen, 1999). Other types of cellulosic fibres are hemp and flax, which can be considered to be the most significant sustainable fibres in the non cotton natural fibre sector (Werf, 2004 Muthu, 2014). 

Natural fibres can be subdivided into plant, animal, and mineral fibres. All plant fibres (cotton, jute, flax, hemp, etc.) are made of cellulose animal fibres are made of protein (wool, silk, hair). Based upon their origin, plant fibres are subdivided into bast and hard fibres. Bast fibres are derived fix)m the stems or stalks of plants hemp, jute, ramie, and flax, for example, belong to this category. Hard fibres, on the other hand, are derived from leaves, leaf sheaths, or fruit sisal and coconut belong to this category ... 

As already mentioned, specific mechanical properties are decisive when using natural fibres in composite materials. The fact that hemp, flax, and ramie natural fibres can compete with technical fibres is demonstrated in Fig 1. 

Morey appears to have been the first to make use of this phenomenon to obtain information about the distribution of orientations of the structural units of the polymer. Most of his observations were made using fluorescent molecules incorporated in natural fibres such as ramie, cotton and flax, but some measurements were made on rayons. He used unpolarised ultra-violet light to excite the fluorescence and expressed his results in terms of a percentage orientation defined as... 

Composites from natural fibres have not yet been fully established in high-tech industry because a sufficient quality for engineering applications is not adequately offered (e.g. by Natural Fiber Composites Inc. and North Wood Plastics). Fibres are available from many plants (highlighted of high quality) for example, wood, abaca, coir, cotton, flax, hemp, henequen, istle, jute, kenaf, ramie, sisal or sunn. 

Composite materials made with natural fibres such as hemp, flax, ramie, banana, jute or chicken feathers as the reinforcing agents, and... 

The two main sources of natural fibres are plants and animals. The main component of animal based fibres is various proteins examples include mohair, wool, silk, alpaca, angora, etc. The components of plant fibres are cellulose microfibrils dispersed in an amorphous matrix of lignin and hemi-cellulose examples include cotton, jute, flax, ramie, sisal, hemp, etc. 

The employment of natural fibres, such as cellulose pulp, sisal, bamboo, hemp, flax, jute, ramie fibres, etc., is restricted to countries where these fibres are easily available. They are important constituents of structural elements used for construction of inexpensive buildings in developing regions of the world (Coutts, 2005). In Africa, sisal fibre-reinforced concrete has been nsed extensively for making roof tiles, corrugated sheets, pipes, silos, and gas and water tanks. Subrahmanyam (1984) cited the application of elephant grass... 

Nowadays, the main producer countries are reported to be China, Brazil, Philippines, India, South Korea and Thailand, but the available statistics are not reliable. This is because production statistics for ramie are included in the Fibre Crops NES (Not Elsewhere Specified) in the official FAO Production Statistics (FAO 1995). Ramie usage in the US increased in the mid-1980s with the emphasis of fashion on natural fibres. 

Natural origin eeo fibre - Organic cotton, organic silk, Ahimsa silk, organic wool. Hemp, bamboo, Kenaf, jute, Sasawashi, Nettle, Sisal, Coconut fibre or Coir, [Banana] fibre. Ramie and Mesta/Roselle. Highly processed natural origin fibre - Rayon type Modal, Lyocell/ Tencel, Ingeo, Seacell. 

The use of natural fibre fabric is an alternative method for geo-engineering applications. The biodegradability of natural fibres has led to their use in short-term geotechnical applications to fulfil technical requirements to temporarily protect and enable the natural growth of local foliage in land and waterway reclamation, restoration or development. Natural fibres such as jute, coir, sisal, kenaf, ramie and other low-cost natural materials such as palm leaves, wood and split bamboo are also used in geotechnical applications such as erosion control, soil stabilization and soil reinforcement. 

Blends of two or more biopolymers are not presented here, they are included in the paragraph describing the main constituent of their matrix. Starch or lignin are often added as a filler. Depending on their concentration, these blends are described in the section dedicated to starch/lignin or to their main matrix component. The main natural fibres that can be added to biopolymers are cotton, jute, flax, hemp, ramie/china grass, sisal, kenaf, kapok and abaca (Beckwith, 2003). Table 1.2 summarises the major properties of these fibres (Drzal et al, 2002)... 

Cotton and Other Cellulosic Fibres. The dominant natural cellulosic fibre is cotton, the other natural cellulosic fibres, or bast fibres, include flax, linen, jute and ramie. The so-called regenerated fibres, which include viscose, modal fibres and lyoceU (Tencel), are made by various chemical treatments of cellulosic substrates. The dyeing and printing of cellulosic fibres and materials is carried out using, in decreasing order of scale and importance, reactive, direct and vat dyes. ... 

This reagent, applied to natural, dry fibres, colours the cellulose of cotton, flax, hemp, ramie, etc., violet, and that of wood blue, while lignified fibres are dyed yellow. 

Ramie can be spun alone or with cotton and mercerization gives an increased lustre and a loss of hairiness. When the mercerization is carried out without tension the fibre becomes twisted and very like natural cotton in appearance B in Fig. 4.5), but under full tension no twist appears and the fibre bears a closer resemblance to mercerized cotton, (Fig. 4.5 A). 

Chief constituent of the cellular tissue or fibre of plants. Cotton is the purest natural form and contains about 90%. Flax, hemp, ramie, etc., are less pure forms. Present in wood and straw (30-40%). The action of 17-18% NaOH dis-tinguishes three celluloses, viz. a c ulose (insol), cellulose (sol. and re-pptd. by acids), and y>cellulose (permanently sol.). a-Cellulose is that normally referred to as pure cellulose. It is insol. in all ord. org. solvents, but dissolves in cold 70% HgS04 (re-pptd on dilution— hydrocellulose), cone. ZnGg-Aq., ammoniacal copper hydroxide sol. (Schweizer s reagent), and in NaOH + CS2 (forms sodium xanthogenate). Does not react with phenylhydrazine or hydr-oxylamine. TaJres up one mol. NaOH for each CgHipOs unit, the NaOH being recovered by... 

Nature in its abundance offers us a lot of material that can be called fibrous fibres are found in plant leaves, fraits, seed covers and stalk. Fibres from these plants can be considered to be totally renewable and biodegradable. Bast fibres are soft, woody fibres obtained from stems of dicotyledonous plants (flowering plants with net-veined leaves). Such fibres, usually characterized by fineness and flexibility, are also known as soft fibres, distinguishing them from the coarser, less flexible fibres of the leaf, or hard , fibre group. This chapter will discuss bast fibres from flax, hemp, jute, ramie, kenaf and abaca. 

Ramie fibres are found in the bark of the stalk the fibre is very fine and silk-like, naturally white in colour and has a high lustre. The process of transforming ramie fibre into fabric is similar to processing linen from flax. 

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