Super Absorbent Fibers

Sodium polyacrylate also named acrylic sodium salt polymer or simply ASAP (repeating unit -CH2-CH(COONa)-) is a polymer widely used in consumer products. Acrylate polymers generally are considered to possess an anionic charge. While sodium neutralized acrylates are the most common form used in industry, there are also other salts available including potassium, lithium, and ammonium. 

Acrylates and acrylic chemistry have a wide variety of industrial uses that include  

Sequestering agents in detergents. (By binding hard water elements such as Ca and Mg, the surfactants in detergents work more efficiently.) 

Super absorbent polymers. These cross-linked acrylic polymers are used in baby diapers. Copolymer versions are used in agriculture and other specialty absorbent applications. 

These cross-linked acrylic polymers are referred to as Super Absorbents and Water Crystals . The origins of super absorbent polymer chemistry trace back to the early 1960s when the US Department of Agriculture developed the first super absorbent polymer material. This chemical is featured in the Maximum Absorbency Garment used by NASA. 

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Many other high volume consumer products make use of one or more core layers with absorbent properties. Among the most quickly and highly developed applications are baby diapers, which use super absorbent fibers. Super absorbent polymer (SAP) molecules can trap and hold hundreds to thousands of times their own weight in fluid, ultimately forming a gel. The super absorbent core layer in a diaper is between a non-woven cover stock, a one or two layer non-woven fluff/pulp sheet that takes up, distributes, and draws liquid into the core, and a microporous back sheet. In addition, elastomeric materials and waterproof elements are incorporated. The super absorbent core not only stores liquid but actively pulls moisture out of the damp or even wet fluff/ pulp, thus leaving the contact areas soft and dry. 

Fibers are the basic element of nonwovens world consumption of fibers in nonwoven production is 63% polypropylene, 23% polyester, 8% viscose rayon, 2% acrylic, 1.5% polyamide and 3% other high performance fibers [8]. The data in Fig. 10.4 shows the market share of important polymers and fibers in the nonwovens market. Manufacturers of nonwoven products can make use of almost any kind of fibers. These include traditional textile fibers, as well as recently developed hi-tech fibers. Future advancements will be in bicomponent fibers, micro-fibers (split bicomponent fibers or meltblown nonwovens), nano-fibers, biodegradable fibers, super-absorbent fibers and high performance fibers. The selection of raw fibers, to a considerable degree, determines the properties of the final nonwoven products. The selection of fibers also depends on customer requirement, cost, processability, changes of properties because of web formation and consolidation. The fibers can be in the form of filament, staple fiber or even yam. 

Biotechnology research is seeking to develop new foods, feeds, fiber, and biomass energy production processes that are environmentally safe. Researchers are developing new uses for agricultural products to replace non-renewable sources of raw materials. Their work promises to have broad commercial applications and has already led to the creation of new industries. These discoveries have led to environmentally compatible commercial products such as biodegradable plastics (60), soybean oil printing inks, and super absorbent polymers (67). 

M. Likon, M. Remskar, V. Ducmcui, cUid F. Svegl, Populus seed fibers is a natural source for production of oil super absorbents. J. Environ. Manag. 114,158-167 (2013). 

Hygiene products normally consist of several layers of various materials. They are distinguished into covering and inside layers. The covering layer is normally produced as a thin nonwoven. Very often the material for covering layers is cotton or cellulose. For a long time the inside layer was also made of cotton or cellulose. At present more and more webs are made of hydrophilic chemical fibers and so-called super absorbers. ... 

Acrylic acid is an important chemical building block used in the manufacture of polyacrylates and commodity acrylates. Commodity acrylates, such as methyl, ethyl, n-butyl, and 2-ethylhexyl acrylate, are utilized in various industrial applications, including coatings, adhesives and sealants, textiles and fibers, polymer additives/impact modifiers, and films. Polyacrylates are extensively used as super absorbent polymers. Bio-based acrylic acid can be obtained through the fermentation of carbohydrates to 3-hydroxypropionic acid (3-HPA), and further dehydration of 3-HPA gives acrylic acid. 3-HPA could also be used as a precursor to other important chemical building blocks, such as PDO, acrylonitrile, and acrylamide. Via another route, glycerol can be chemically converted to acrylic acid, either by dehydration to acrolein followed by oxidation to the final product or in a one-step oxydehydration. 

SNS Nano Fiber Tehcnology, LLC USA http //www.snsnano. com/ PM, CS NANOSAN (super absorbant pad) Needle, coaxial US20090093585 Al Own design... 

The basis of this process was the injection of sodium carbonate solution into the viscose, although direct injection of carbon dioxide gas that reacts with the viscose soda to form sodium carbonate could also be used (44). The carbonate route yielded a family of inflated fibers culminating in the absorbent multilimbed super inflated (SI) fiber (Eig. 5c). 

Super submicron technology is now available to produce antimony synergist with particle sizes below 1 pm. The advantages include applications in flame-retarded fiber without screen-packing problems and reduced UV light absorbency. This will allow next-generation systems to enhance flame-retardant performance and UV durability at the same time. 

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