Blended fibre fabrics

For polyamide/wool blended fabrics fluorescent brightening agents (1 -2%) are applied following hydrogen peroxide bleaching in presence of stabiliser (3-5 g/1). The treatment is carried out at 70-75 C for 45-60 min and then rinsed and dried. 

For acrylic/wool blends, the acrylic portion is brightened in the normal way and then the wool is bleached with hydrogen peroxide and subsequent reduction bleaching is done in a bath containing suitable brightener (1-2%) and stabilised sodium hydrosulphite (3-5 g/1) at 85 C for 30 min. The fabric is then rinsed and dried. 

For polyamide/acrylic blends, both the fibres can be brightened by using suitable disperse type brighteners at 95-98 C for 30-60 min, cooled, rinsed well and dried. Where bleaching is necessary, a suitable brightener stable to chlorite may be included in the bleach bath. 

Textile Wet Processes,Vol I, Noyes Pub., Park Ridge, New Jersey, USA (1983) p 153. 

4 Millos Zahradnik, The Production and Application of FBAs, John Wiley Sons, Chichester, Sussex (1982) p 14. 

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Acrylic/wool blended fibre fabrics may be prepared according to established practice for wool, except that precautions are taken to allow for the thermoplastic properties for the acrylic fibres. Relaxation is done to remove the inherent strain. Worsted fabrics are crabbed and then scoured in either a Dolly at temperature not exceeding 40 C or in winch. 

In tropical countries like India synthetic fibres blended with cellulosic fibres fabrics are very popular due to their excellent combination of aesthetic properties and easy care properties. Thus, bleaching of blended fibre fabrics before further processing is an important step. Many of the preparatory processes used for natural and synthetic fibres have little or no application in preparation of blended fibre fabircs. 

Desizing of Synthetic Fibre Fabrics and Their Blends with Cellulose... 

This process is used to recycle fabrics made from natural fibres such as cotton and wool as well as synthetic fibres including polyesters, nylons and blended fibres. Hawley (2006) describes the mechanical processing technique used in facilities in Prato, Italy, where acrylic textiles are shredded down to fibre. In hw example, acrylic garments were sorted and cut up, mechanically shredded to fibre, and then re-spun into acrylic yam for weaving into blanketing (Hawley, 2006). 

From Figures 1, 3,4 5 it could be seen that the 100% bamboo fibre fabric is able to inhibit the bacterial growth to a greater extent riien compared to the bamboo fibre/cotton blended febrics and it could be seen from Fig.S that the 50 50 bamboo fibre cotton blend inhibiting bacterial growth to the lowest extent... 

Sr. No. Fibre Type (Blend Ratio) Fabric Mass Thread count Air Perme ability Applicat ion of febric Sample Code... 

Figure 8.11 shows the percentage exhaustion of red, yellow and blue colour dyes on a fabric made of polyester, cotton and wool blended fibres versus time. Ideally, the acid dyes adsorb onto the wool, the direct dyes adsorb onto the cotton, and the disperse dyes adsorb into the polyester fibres. Figure 8.11 shows that. 

Essentially nonionic soil-release agents comprise polyesters, polyamides, polyurethanes, polyepoxides and polyacetals. These have been used mainly on polyester and polyester/ cellulosic fabrics, either crosslinked to effect insolubilisation (if necessary) or by surface adsorption at relatively low temperature. Polyester soil-release finishes have been most important, particularly for polyester fibres and their blends with cellulosic fibres. These finishes, however, have much lower relative molecular mass (1000 to 100 000) than polyester fibres and hence contain a greater proportion of hydrophilic hydroxy groups. They have been particularly useful for application in laundering processes. These essentially nonionic polymers may be given anionic character by copolymerising with, for example, the carboxylated polymers mentioned earlier these hybrid types are generally applied with durable press finishes. 

In a recent detailed evaluation of Cl Fluorescent Brightener 393 on polyester, this product was incorporated into the polymer melt. The prebrightened fibre was blended with cotton and fabric knitted from these yarns was scoured and bleached. It was demonstrated... 

Over the past 20 years no new commodity polymer has been developed. This is because of the advances in fabrication, blends (both miscible and non-miscible), fibre reinforcement, etc. Thus films with up to 11 different polymer layers have been developed. 

Providing flame retardancy for fibre blends has proved to be a difficult task. Fibre blends, especially blends of natural fibres with synthetic fibres, usually exhibit a flammability that is worse than that of either component alone. Natural fibres develop a great deal of char during pyrolysis, whereas synthetic fibres often melt and drip when heated. This combination of thermal properties in a fabric made from a fibre blend results in a situation where the melted synthetic material is held in the contact with the heat source by the charred natural fibre. The natural fibre char acts as a candle wick for the molten synthetic material, allowing it to bum readily. This can be demonstrated by the LOl values of cotton (18-19), polyester (20-21) and a 50/50 blend of both (LOl 18), indicating ahigher flammability of the blend as described later (Section 8.11). But a rare case of the opposite behaviour is also known (modacrylic fibres with LOl 33 and cotton in blends from 40-60 % can raise the LOl to 35). 

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