Textile fibers polyolefins

The main requirements for good textile fiber are (a) a Tt below room temperature (to provide flexibility at normal temperatures), together with (b) microcrystallinity to provide strength, orientability, and (sometimes) ease of fabrication by melting. The classical organic polymers used for fibers (Nylons, polyesters, and polyolefins) generally have these characteristics. 

The world textile industry is one of the largest consumers of dyestuffs. An understanding of the chemistry of textile fibers is necessary to select an appropriate dye from each of the several dye classes so that the textile product requirements for proper shade, fastness, and economics are achieved. The properties of some of the more commercially important natural and synthetic fibers are briefly discussed in this section. The natural fibers may be from plant sources (such as cotton and flax), animal sources (such as wool and silk), or chemically modified natural materials (such as rayon and acetate fibers). The synthetic fibers include nylon, polyester, acrylics, polyolefins, and spindex. The various types of fiber along with the type of dye needed are summarized in Table 8.2. 

Polyolefin textile fibers are usually produced through the melt spinning process with good mechanical properties and chemical and abrasion resistance. One of the main drawbacks in this industry is the fact that they are difficult to dye unless additives are used. One of the major applications of PP is the use in carpet which replaced natural fibers. Other apphcations include bags, sportswear, and knitwear. 

Polyolefins such as polyethylene (PE) and polypropylene (PP) are known for their lightweight, ease of processing, excellent chemical resistance, water repellency, and reasonable strength and tenacity. This makes them the material of choice for many textile fibers and nonwoven applications. 

Fiber spinning process Melting spinning is the common process used to make textile-type polyolefin fibers (UHMWPE is an exception due to its ultra-high molecular weight as will be seen later). The process of making continuous filament yam consists of the following steps [2] ... 

Polyolefin fibers, on the other hand, have some drawbacks when compared to common textile fibers such as polyester. These limitations include relatively lower resiliency, creeping due to their low glass transition temperature (Tg), poor... 

Polymeric materials then, whether natural (such as cellulose, resins, and proteins) or synthetic (such as polyolefins, nylons, and acrylics), behave in reproducible ways when exposed to pyrolysis temperatures. This permits the use of pyrolysis as a sample preparation technique to allow the analysis of complex materials using routine laboratory instruments. Pyrolytic devices may now be interfaced easily to gas chromatographs, mass spectrometers, and FT-IR spectrometers, extending their use to solid, opaque, and multicomponent materials. Laboratories have long made use of pyrolysis for the analysis of paint flakes, textile fibers, and natural and synthetic rubber and adhesives. The list of applications has been expanded to include documents, artwork, biological materials, antiquities, and other complex systems that may be analyzed with or without the separation of various layers and components involved. 

Guanidine sulfamate is utilized as a flame retardant for PVC wall coverings in Japan. Guanidine phosphate is added as a flame retardant to textile fibers and mixtures based on melamine phosphate are used as flame retardants to polyolefins or glass reinforced nylons. 

In this survey, commercially important textile fibers are grouped by their origin. First there are the natural fibers from plant sources, cotton and flax, and those from animal sources, wool and silk. A second group consists of those fibers that are regenerated or chemically modified natural materials—the rayon and acetate fibers. The final group consists of the synthetic fibers, which include nylon, polyester, acrylics, polyolefins, and spandex. 

P.R.170 is not always heat stable enough to allow application in polyolefins. In HDPE systems formulated at 1/3 SD, the pigment tolerates exposure to 220 to 240°C for one minute. Its tinctorial strength, on the other hand, is excellent. P.R.170 is also occasionally used in polypropylene and polyacrylonitrile spin dyeing in the latter medium, it satisfies the specifications of the clothing and home textiles industries. Besides, P.R.170 lends color to viscose rayon and viscose cellulose it is used for the mass coloration of semisynthetic fibers made of cellulose last but not least, it colors yarns, fibers, and films made of secondary acetate. 

Cyclic oligomeric phosphonates with the varying degrees of structural complexity (Structure 5.4) are also available in the market.25 They are widely used as flame-retardant finishes for polyester fabrics. After the phosphonate is applied from an aqueous solution, the fabric is heated to swell and soften the fibers, thus allowing the phosphonate to be absorbed and strongly held. It is also a useful retardant in polyester resins, polyurethanes, polycarbonates, polyamide-6, and in textile back coatings. A bicyclic pentaerythritol phosphate has been more recently introduced into the market for use in thermosets as well as for polyolefins (preferably, in combination with melamine or ammonium polyphosphate)... 

Melamine diborate (MB), known in the fire-retardant trade as melamine borate, is a white powder, which can be prepared readily from melamine and boric acid. It is partly soluble in water and acts as an afterglow suppressant and a char promoter in cellulosic materials. Budenheim Iberica79 claims that, in a 1 1 combination with APP, MB (10%-15%) can be used for phenolic bound nonwoven cotton fibers. In general, melamine borate can be used as a char promoter in intumescent systems for various polymers including polyolefins or elastomers. However, its low dehydration temperature (about 130°C) limits its application in thermoplastics that are processed at above 130°C. Melamine borate is also reported to suppress afterglow combustion in flame-proofing textiles with APP or monoammonium phosphate to meet the German DIN 53,459 and Nordtest NT-Fire 002.80... 

Textile Additive to improve dyeability and antistatic properties of polyolefin, polyester, and polyamide fibers... 

Addition of micro- or nanofiUers or additives to the polyolefins can improve their properties for different modem applications such as in the automotive, furniture, medical, packaging, electrical, transportation, constmction, textile, and agriculture industries. These industries have been increasing over the last few decades. Additives can include diflerent shapes such as flakes, fibers, and particulate types. It can be of natural or synthetic nature. The additives can improve the performance of the new composites or nanocomposites of the polyolefins. 

PP is the most used polymer in the polyolefin family for textile applications. Fabric and fibers composed of POCs keep carpets clean and dry. They maintain germffee environments and can soak up industrial spills. POC-based textiles and fabrics are used in flexible intermediate bulk containers (FIBCs) for transporting industrial and construction materials in bulk [82]. PP-based polyetheresteramide... 

Polyolefins are increasingly becoming an integral part of the textile and nonwoven industries. Even though they have not historically enjoyed the same fame achieved by polyester and nylon in synthetic fiber applications, polyolefins offer... 

It will be uselul for the reader to establish some basic definitions related to the topic before we proceed. The main component of the textile or nonwoven fabric is the fiber therefore, polyolefin fiber will be defined first. 

The focus in this chapter will be on the two main polyolefin polymers, namely polyethylene (PE) and polypropylene (PP). The latter especially has established itself as a very versatile fiber with unique applications in the textile and nonwoven industry. Polyethylene, on the other hand, has not been widely used as a fiber compared to other synthetic polymers such as PET, PP, and nylon, due in part to its low melting point. This chapter will, however, discuss ultra-high molecular weight polyethylene (UHMWPE) fiber that given its success and uniqueness in the synthetic fiber industry. 

The central component of a textile fabric is the fiber, which could be natural such as cotton or wool, or synthetic such as polyester or polypropylene. Since the chapter is concerned with polyolefins, the various forms of synthetic fibers used in the textile industry will be mentioned. Fibers for the textile industry could take any of the following forms before being knitted or woven into a final textile fabric form ... 

Tenacity. It is the stress at which the fiber breaks, expressed in grams per denier. It is a very important property of polyolefin fibers, and it can range between 3.5 and 8 g/d (grams per denier) or 31-81 g/tex [10]. General textile use PP fibers can have a tenacity of 40.5-50 cN/dtex, whereas high tenacity yams used in ropes and nets can have tenacities up to 81 cN/dtex [11]. 

CAS 7128-64-5 EINECS/ELINCS 230-426-4 Uses Fluorescent whitener, optical brightener for thermoplastics (PVC, PE, PP, cellulose acetate, PS, PC, acrylics, polyolefins, PU, linear polyester, polyamides), adhesives, coatings, printing inks (for security bonds, bank notes), dyes, textiles (syn. fibers incl. PVC and acetate), molded articles, films, sheets, syn. leather, waxes, fats, and oils tracer in clear coatings... 

J. G. Cook, Handbook of Polyolefin Fibers, Textile Book Service, London, 1967. 

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