Modified fibres polyester

TXRF has also been used for the characterisation of single, colourless textile fibres (polyesters, modified cellulose and wool), yielding a fingerprint trace-element pattern, suitable for forensic purposes [276,277], Sample preparation involved dissolution/predigestion in HN03 and matrix removal (O2 cold plasma). 

Research into controlled-release antimicrobials continues with organo-silver compounds and silver zeolites, which are promising candidates for textile finishes. Silver ions, for example, incorporated in glass ceramic, have a very low toxicity profile and excellent heat stability. These principles are also used for fibre modification, an alternative to the antimicrobial finishes with high permanence. In recent years a variety of antimicrobial modified fibres have been developed, including polyester, nylon, polypropylene and acrylic types. An example of these fibre modifications is the incorporation of 0.5-2 % of organic nitro compounds... 

Fibre choices for thermal protective clothing include inherently flame resistant (FR) fibres such as the meta- and para-aramids, polyamide-imide, polybenzimidazole, modacrylic and chemically modified fibres such as viscose and modal, polyester, and nylon, as well as FR treated or finished cotton and wooP"" (see also Chapter 8). The... 

Pothan C, Thomas S, Groeninckx G (2006) The role of fibre/matrix interactions on the dynamic mechanical properties of chemically modified banana fibre/polyester. Compos A 37 1260-1269... 

The thermal behavior of the composites based on raw and surface modified Grewia optiva particle fibres reinforced unsaturated polyester matrix was studied [47]. The fibres were modified by mercerization, silanation, benzoylation and graft copolymerization. The thermal stability of the composites containing modified fibres was improved compared to the unsaturated polyester matrix and to the composites containing untreated fibres. This was a consequence of the additional intermolecular bonding between fibres and matrix induced by the surface modification. The highest thermal stability was obtained by the composites based on silanated fibres due to the formation of strong covalent bonds between silanes and cellulose. 

Acid dyes Reactive dyes Basic Direct dyes Mordant dyes Disperse dyes Vat dyes Solvent dyes Fluorescent brightners Other dye classes Nylon, sUk, wool, paper, inks and leather Cotton, wool, sUk and nylon Paper, polyacrylonitrile, modified nylon, polyester and inks Cotton, rayon, paper, leather and nylon Wool, leather and anodised altiminirun Polyester, polyamide, acetate, acrylic and plastics Cotton, rayon and wool Plastics, gasoline, varnishes, lacquers, stains, inks, fats, oils and waxes Soaps and detergents, aU fibres, oils, paints and plastics Food, drugs and cosmetics, electrography, direct and thermal transfer printing... 

Many brilliantly coloured and tinctorially strong basic dyes for silk and tannin-mordanted cotton were developed in the early decades of the synthetic dye industry. Most of these belonged to the acridine, azine, oxazine, triarylmethane, xanthene and related chemical classes their molecules are usually characterised by one delocalised positive charge. Thus in crystal violet (1.29) the cationic charge is shared between the three equivalent methylated p-amino nitrogen atoms. A few of these traditional basic dyes are still of some interest in the dyeing of acrylic fibres, notably as components of cheap mixture navies and blacks, but many modified basic dyes were introduced from the 1950s onwards for acrylic and modacrylic fibres, as well as for basic-dyeable variants of nylon and polyester [44] ... 

Quite small variations in disperse dye structure can markedly modify substantivity for polyester [89]. This is evident from Figure 3.4, where the two blue dye structures differ only in the 3-acylamino substituent of the diethylaniline coupling component. Replacing acetylamino by propionylamino in dye 3.74 increases the colour yield by at least 30% for a 1.5% depth applied to polyester fibre for 45 minutes at 130 °C. An even more striking example is provided in Figure 3.5, illustrating two isomeric greenish blue dyes applied to... 

Manfredi, L. B., Rodriguez, E. S., Wladyka-Przybylak, M., and Vazquez, A. Thermal degradation and fire resistance of unsaturated polyester, modified acrylic resins and their composites with natural fibres, Polym. Degrad. Stabil. 2006, 91, 255-261. 

There are different ways that low energy surfaces can be applied to textiles. The first way is mechanical incorporation of the water-repellent prodncts in or on the fibre and fabric surface, in the fibre pores and in the spacing between the fibres and the yams. Examples of these are paraffin emulsions. Another approach is the chemical reaction of the repellent material with the fibre snrface. Examples of these are fatty acid resins. Yet another method is the formation of a repellent fihn on the fibre surface. Examples of these are silicone and flnorocarbon prodncts. The final approach is to use special fabric constructions like stretched polytetrafluoroethylene films (Goretex), films of hydrophilic polyester (Sympatex) and microporous coatings (hydrophilic modified polynrethanes). 

The most successful approach for flame-retarding acrylic fibres is to copolymerise halogen-containing monomers into the fibre. These modacrylic fibres have excellent permanent flame retardancy and acceptable fibre properties. Some problems including reproducibility of dyeing gave rise to their substitution by flame-retardant modified polyester, for example for curtain fabrics and other decorative textiles. 

Pill curves for fabrics with normal and modified polyester fibres. 

CNC REZ K is a modified ethylene urea formaldehyde resin which was created to give the finisher a thermosetting resin which possesses all of the outstanding features of cyclic resins as to shrinkage control, crease resistance, hand appeal and also not detract from soil release properties. This resin gives fairly soft hand on all classes of fibres and is exceptionally durable on the polyester/cotton blends. 

Volume 8 Needle Punching Textile Technology by V. Mrstina anc/F. Fejgl Volume 9 Industrial Textiles edited by J. Svedova Volume 10 Modified Polyester Fibres byJ. Militky etal. 

Terylene, like nylon, is thermoplastic and can have permanent pleats or shapes imposed by the action of heat with or without steam. It breaks under loads of 4-2 to 4-8 g per denier and the continuous filament has an extension of 22 to 30 per cent at the breaking point. The fibre has marked crystallinity as shown by the X-ray diffraction diagram illustrated in Fig. 2.7, and by the low moisture regain of 0-4 per cent. The closely packed and highly-orientated molecules make Terylene markedly hydrophobic and difficult to dye. Modified polyester fibres are produced with an affinity for both disperse and cationic dyes. 

In the case of the pale shades the two fibres can be dyed in the same liquor with a disperse and an acid milling or a premetallized dye, and subsequently cleared with permanganate in the manner described in the previous paragraph. With dark colours it is better to dye the polyester first then clear the wool with sodium hydrosulphite, ammonia, and a non-ionu dispersing agent, and finally match the protein fibre with acid or premetallized colours. It must be borne in mind that when after-chrome dyes art used, some disperse dyestuffs are modified by the dichromate, with change of colour. C.I. disperse red 11 (Cibacet Brilliant Pink 4BN) anc C.I. DISPERSE RED 15 (Duranol Red 2B) are particularly susceptible, anc C.I. DISPERSE RED 13 (Cibacet Rubine R) should be substituted. 

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