Nonwovens applications

Zhang, Y., Yarin, Ai., 2009. Stimuli-responsive copolymers of n-isopropyl acrylamide with enhanced longevity in water for micro- and nanofluidics, drug delivery and nonwoven applications. Journals of Materials Chemistry 19, 4732—4739. 

Natural cellulose tibers such as cotton, ramie, etc. have been used as blends for textile applications. High modulus regenerated cellulose tibers are produced on a commercial scale. For instance, Lyocell , a high performance ceUulosic tiber, has been used in many nonwoven applications because of its high strength, durability, absorbency, purity and biodegradability. 

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. 

This chapter will provide a concise summary of the main technologies and applications. Distinction will be made between PE and PP in terms of their suitability for specific fiber and nonwoven applications. Resin choice, in terms of its molecular weight and formulation, is critical not just to the final product performance but also to the type of technology used to convert the resin. 

As for viscose fibres, these are mostly produced as staple fibres for textile and nonwoven applications. In 2011, world production was 3.246 million tons [49] while filament yam for textile and technical applications reached 332 000 tons in 2011 [49] with a share of technical yarns of 56 000 tons. Technical viscose fibres, also called rayon or viscose rayon, are used mainly as carcass reinforcing fibres in fast-running and run-flat tyres. Lyocell fibres are produced only as staple and virtually exclusively by Lenzing AG, Austria, with a production capacity of 140 000 tons in 2011 [50]. 

A large amount of fibrous waste is generated each year, consisting of a variety of synthetic and natural polymers. Frequently, different types of polymers and other materials are integrated to form an article, such as blended textiles, carpets, conveyer belts, to name a few. Much of the textile waste collected could be re-used directly, be used as wipes, or be shredded for filling or nonwoven applications. Post-consumer carpet, on the other hand, is a more complex system that often requires extensive processing to convert it into products. 

Life Sri Italy. Development and manufacture of silver-coated manmade staple fiber and filaments for textile and nonwovens applications in industrial, safety, and medical products... 

Olefin fiber is an important material for nonwovens (74). The geotextile market is still small, despite expectations that polypropylene is to be the principal fiber in such applications. Disposable nonwoven applications include hygienic cover-stock, sanitary wipes, and medical roll goods. The two competing processes for the coverstock market are thermal-bonded carded staple and spimbond, both of which have displaced latex-bonded polyester because of improved strength, softness, and inertness. 

The last few years have seen a huge growth of lyoceU in nonwoven applications. The fibriUation property can deliver significant performance benefits and sustained growth is expected in the key areas of wet wipes and filtration. 

Macfarlane, Keith, Nonwovens applications of lyocell fiber , World Text. Congr. Nat. Nat.-Polym. Fibres, 131-139, 1997. 

Exhibit 1.1 Key automotive nonwoven applications. 1, Door and side panelling 2, Underbody covers 3, Airbag covers 4, Floor and footwell covers 5, Rear of seat 6, Brake disks ... 

Figure 1.6 Highest growth automotive nonwoven applications. Source Data Kellie Solutions.

In Fig. 1.6, we have set out some of the fastest growing nonwovens applications in automotive. 

Figure 1.7 Projected nonwoven applications in automotive 2020 (m ). Source Data Kellie Solutions Ltd.

Many companies now incorporate the desire for sustainable practice into company policy, and this culture change is seen as an important driver for generating innovative and environmentally considerate solutions (EDANA, 2015). As research and development into new materials and processes continues, it is expected that the relative price of biopolymers and biodegradable polymers will reduce, thus broadening the range of nonwoven applications they are expected to be found in. It should also be reiterated that the use of nonwoven materials would go some way to minimising the... 

The use of nanofibre in nonwoven applications is an exciting and developing area of fibrous materials. Although nanofibres have been successfully employed in filtration applications for several decades and many applications are still in the development... 

The nonwoven fabric mass per unit area and thickness usually vary in different locations in the fabric plane. The variation of either nonwoven thickness and/or fabric area weight determine the variation of local fabric packing density, local fabric porosity, and pore size distribution, and it thus influences the performance of nonwoven applications, such as the appearance, tensile properties, permeability, thermal insulation, sound insulation, filtration, liquid barrier and penetration, energy absorption, light opacity, and processability of nonwoven products. 

Not only the time for a hquid droplet striking through a nonwoven fabric and liquid wicking rate are important, the rate of liquid absorption (or the period of time taken for nonwoven fabrics to reach saturated status) and the capacity of a nonwoven fabric to retain the hquid, the liquid absorbency, or the liquid absorption capacity are also crucial for nonwoven applications such as hygiene, wiping, and other absorbent nonwoven materials. The methods used to assess the rate of hquid absorption and the hquid absorption capacities are dehned in INDA/EDANA and ISO standards. For example ... 

The methods related to the evaluation of the specific nonwoven applications have also been defined in various standards the typical examples of such technical products are nonwoven wound dressings and nonwoven filters. 

INDA. Some typical examples of nonwoven applications are as follows ... 

One of the most successful composite nonwoven applications is the use of needle-punched nonwovens as wheel arch liners. These are the first nonwoven composites to be used as exterior automotive parts. The textile wheel arch liner was developed by Borgers in 1995. 

Historically, the packaging sector has been a small and somewhat neglected part of the wide range of nonwoven applications. We have been able to study it in detail over an extended period. In this assessment, we have updated our work to show just how significant this sector has become and the factors driving its growth. 

In general, thermoplastic elastomer hot-melt adhesives are not as strong as polyesters. However, they exhibit good flexibility, high elongation, toughness, and vibration resistance. Polyurethanes and block terpolymers are used as hot-melt pressure-sensitive adhesives in tapes and labels and for nonwoven applications. 

Improved evenness of finish coverage and better friction performance have given benefits in several nonwoven applications ... 

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