Pile resilience

Pile resilience, improved stand of pile by better elastic resilience Pile fabrics... 

To make cut pile carpets, two strands of BCF yarns are twisted together and heat-set with steam using a Superba heat setting machine at 135-145 °C or at 175-195 °C when heat-set with super-heated steam in a Suessen. An experimental design experiment [94] showed the higher the heat set temperature, then the lower is the bulk of the final carpet, but there is an increase in the tip definition and walk performance. The tufted carpets are then dyed with disperse dyes at atmospheric boil [95] in a continuous or a batch process. PTT carpets showed excellent resiliency in walk test experiments, equivalent to a nylon and much better than both PET and polypropylene, had lower static charge of <3.5 kV, and were resistant to coffee, mustard, betadine, red acid dyes and other stains [96],... 

Resilience of textile fabrics when compressed in the bent state is related to wrinkle resistance and retention of shape, drape, and hand. Resilience is an important parameter for evaluating blankets, wearing apparel in which warmth is a factor, pile fabrics including carpets, and bulk fiber utilization in mattresses, cushions, etc. The general method for determining compressional resilience is to compress and unload the material cyclically, creating a plot of compressive force versus fabric thickness. 

Dynamic Effects. Particles often differ in their resilience, inertia, and other dynamic characteristics which can cause them to segregate, particulady when they are forming a pile such as when charged into a bin or discharged from a chute. 

Modified polyurethanes as shown in Fig. 4.6 are used for valuable hand variations and as additives for cellulose crosslinkers. Their flexible and elastic films on the fibre surface improve elastic resilience, which is, for example, important for pile fabrics. The principle of their elasticity is, as in elastan fibres, the molecular combination of so-called weak and hard segments. The large weak... 

The carpet market is one area in which acrylics have failed as a result of inadequate hot-wet stability. Although acrylic fibers produce a carpet of superior wool-like appearance and quality, the pile loses its resilience and bulk during dyeing and under high-humidity conditions. To compensate, acrylic carpets must be made in expensive, high-density constructions. As a result, acrylics have lost popularity as a carpet fiber since the peak year of 1968. 

Despite their decline in popularity, acrylic and modacrylic carpet fibers allow exceptional versatility in styling and color patterns. Acrylic carpets can also be superior to nylon esthetically, but dense and expensive constructions are required to match the pile height and durability of nylon carpets. In less dense constructions, acrylic carpets can develop wear patterns and pilling. Without the dense constructions acrylic carpet can also lose resilience and pile height in the dye bath or in service under hot, humid conditions. 

A breakdown of U.S. domestic synthetic staple and tow fiber shipments by end use is given in Table 12.33. Organized by fiber type and application, these data show that acrylic fiber is strongest in hosiery, sweaters, craft yarns, pile fabrics, circular knits, flat knits, and blankets. Polyester, valued for its low cost and easy-care properties, has a strong hold on the fiberfil, nonwoven, flat-knit and broad-woven fabric markets. Nylon, valued for its durability and resiliency, dominates the carpet market. Olefin, a fiber type that appears to be growing in popularity, has great impact on the nonwovens market and has made inroads in the carpet face yarn markets versus nylon staple and filament. Table 12.34 shows the same type of data as Table 12.32, but arranged by distribution of end use for each type of synthetic staple and tow fiber. 

The bicomponent fibres are suitable for felts, needle-punched carpets and tiles and upholstery fabrics the appearance of these products is more pleasant than that of uncrimped fibres owing to the absence of gloss and they have a bulkier, softer handle. Continuous crimped yams could be suitable for certain types of stretch fabrics or knitted products but so far these products have not reached the commercial stage. Attempts to use the bicomponent fibres for tufted carpets have not been satisfactory so far for two reasons. One reason is that the resilience of the piles is less than that of wool or nylon. Another reason is that fibrillated fibres may show a tendency towards a further fibrillation under severe wear or abuse. 

Random crystalline terpolymers - EPR For fibers with high resiliency and shrinkage, for pile fabrics Clementini et al. 1993... 

Polypropylene, PP, was blended with a random crystalline terpolymer of 96-85 wt% propylene, 1.5-5.0 wt% ethylene, and 2.5-10 wt% C4 g alpha-olefin. The blends were used to manufacture strands of multiple monofilamcmts m staple fibers with high resiliency and shrinkage, for pile fabric. 

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