Fiber and Nonwoven

PLA is an aliphatic polyester. It is a biodegradable thermoplastic and can be processed to become composites. Its monomer, lactic acid, is derived from renewable plant sources, such as starch and sugar. PLA can be degraded into carbon dioxide and water by an action of suitable fimgi. This means that biodegradable PLA fibers are environment fiiendly material even if the fiber is left in the natural environment. The demand for PLA fibers as a substitute for the present synthetic fibers has been growing greatly in recent years. 

On the other hand, high water vapor transmission rate of PLA makes it a good candidate for fabricating fibers used in garments (e.g., shirts, dresses, underwear, shoes, etc.) to improve their breathability . While PLA fibers are not as wettable as cotton, they exhibit much greater water vapor transmission than aromatic polyesters or nylon fibers. 

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M. Grayson, ed., Enjclopedia of Textiles, Fibers and Nonwoven Fabrics, Wiley-Interscience, 1989, pp. 252, 284. 

The butyrate or octanoate copolymer and butyrate or hexanoate or decanoate terpolymer have properties similar to those of higher-grade LLDPE (linear low-density polyethylene) and higher-grade PET (polyethylene terephthalate). They can be molded or converted into films, fibers, and nonwoven fabrics. The biopolymer is produced by low-cost fermentation or from wastestream substrates. 

Bhat. G.. Hegde. R.. Kamath, M.G., and Deshpande, B., 2006. Nanoclay reinforced fibers and nonwovens. Proceedings of the annual conference and exhibition of the American Association of Textile Chemists and Colorists (AATCC), October 31-November 2. Atlanta, GA. 

EOTF Encyclopedia of Textiles, Fibers, and Nonwoven Fabrics Grayson, Martin John Wiley Sons New York, 1984... 

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. 

FIGURE 8.68 Morphologies of the electrospun PPy/PVCN blend fiber and nonwoven web. (From Kang, T.S., et al., Synth. Met, 151, 61, 2005. With permission.)... 

Polypropylene, 55-90 wt% PP, was blended with poly (1-butene), PB, as a dispersed phase and optionally with up to 10 wt% of low-MW poly(a-olefin-co-ethylene) plastomer compatibilizer. The blends were useful for manufacturing fibers and nonwovens, with good hand and tensile strength ... 

Nodax, under development by Proctor Gamble, is made from renewable sources. It consists of a family of copolymers of 3-hydroxybutyrate and one or more 3-hydroxyalkanoates having a longer side chain, where the side chain has anywhere from 3 to 20 carbon atoms. The structures thereby resemble linear low density polyethylene, with the 3-hydroxybutyrate units providing a basis for crystallinity and the other units introducing structural irregularity and reduced crystallinity. Nodax can be converted into sheets, molded articles, foams, films, fibers, and nonwoven fabrics, and is both biodegradable and compostable. 

In addition to other liquid filters for juice, liquor, wine, oil, or wastewater, air filters for air conditioning or cleaning are also potential applications for PLA fibers and nonwovens. The use of PLA fiber for air filter application as an antibac-terial/antifungal material provides benefit for management of sanitary wastes. 

Haile, W.A., Tincher, M.E. and Williams, F.W., New Biodegradable Copolyester for Fibers and Nonwovens , Proceedings of INTC 2001 Conference, 2001. Nonwovens made from Wool , http //www.canesis.com/annualreports/ 2003 textile highlights.shtm www.naturalnonwovens.com/pr.htm... 

The mechanical properties of PLA are similar to PET plastic. PLA is available in many grades including injection molding, extrusion/ thermoforming, sheet extrusion, fibers and nonwovens, blow molding. 

Lunt, J. (2000). Polylactic acid polymers for fibers and nonwovens. International Fiber Journal, 55, 48-52. 

Polyfunctional oxazoline-terminated unsaturated oligoesters are useful in preparing coatings, caulks, impregnants, adhesives for textiles, leather, plastics, wood, and metals, and binding agents for pigments, fibers, and nonwoven fabrics [60-67]. 

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