Synthetic polymer fibres applications

The physical and chemical properties of a yam are largely those of the fibres or filaments making up the yam. In addition to the natural fibres (mainly cotton, but with some wool and silk), and a small, but growing, number of inorganic fibres, the bulk of filter fabrics is based upon an increasingly wide range of synthetic polymer fibres. The physical and chemical properties can then be tailored to the filtration application by choosing the appropriate polymer for the fibre. 

Polymers nowadays are not difficult to prepare because of the easy availability of the raw materials. Most of the Synthetic polymers are of recent origin but they have made an impact on our daily life. They have found extensive applications in textile fibres, rubber and rubber goods, building materials, packaging, fancy decorating articles and ion-exchange resins. 

The third main class of separation methods, the use of micro-porous and non-porous membranes as semi-permeable barriers (see Figure 2c) is rapidly gaining popularity in industrial separation processes for application to difficult and highly selective separations. Membranes are usually fabricated from natural fibres, synthetic polymers, ceramics or metals, but they may also consist of liquid films. Solid membranes are fabricated into flat sheets, tubes, hollow fibres or spiral-wound sheets. For the micro-porous membranes, separation is effected by differing rates of diffusion through the pores, while for non-porous membranes, separation occurs because of differences in both the solubility in the membrane and the rate of diffusion through the membrane. Table 2 is a compilation of the more common industrial separation operations based on the use of a barrier. A more comprehensive table is given by Seader and Henley.1... 

Natural fibres show many advantages over glass fibres when used as reinforcement of synthetic polymers (see Table 5.1) the relatively high density of glass fibres 2.5 g/cm ) compared to cellulose or ligno-cellulose fibres of 1.5 g/cm makes lightweight applications possible. 

Phenol formaldehyde resins were among the first completely synthetic polymers made [73]. They have found wide commercial application due to their ablative properties, with potential use as high-temperature polymers [74, 75]. Phenolics were among the first synthetic polymers to be filled with fillers such as cotton fibres. 

In many practical applications of synthetic polymers molecular orientation is produced by the fabrication process to give improved properties, especially with regard to stiffness and strength. Well known examples are textile fibres such as Terylene or nylon, polypropylene packaging films and polyester bottles. Most natural materials such as silk and cotton fibres, muscle and bone also show significant molecular orientation. All these synthetic and natural materials are anisotropic, i.e. their properties are different in different directions. 

Nonwoven geotextHes are permeable geosynthetics made of nonwoven materials used with soil, rock, or other geotechnical-related material as an integral part of a civil engineering project, structure, or system. They are frequently made from synthetic polymers such as polypropylene, polyethylene, polyamide, and polyester, as well as natural fibres such as jute, sisal, and coir. The European standards (EN) for the specifications and performance requirements of geotextiles in 11 application areas (roads and other... 

General use of analytical pyrolysis is given in Table 2.23. The earliest application of analytical pyrolysis was the identification of the isoprene unit in rubber in 1860 [565]. Analytical pyrolysis is now extensively applied for the analysis of natural and synthetic polymers, textile fibres, wood products, foods, leather, paints, varnishes, adhesives, paper, biopolymers (proteins, polysaccharides), etc., and allows the study of a broad variety of materials including carpets, clothing, electronic components, upholstery, plastic recyclates, fuel sources, oil paintings, etc. 

Polymers are everywhere, from natural materials like wood or silk to synthetic plastics, fibres and gels. The development of methods for the controlled synthesis of polymers is one of the most important technological advances of this century, ranking alongside the discovery of semiconductors (the basis of the information technology revolution) or more recent advances in the understanding of biomaterials. Polymers have replaced natural materials in many applications, and indeed for some everyday objects it is difficult to imagine them not made from polymers for example wooden or metal telephones are quite unusual. 

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