Non wovens

The primary non-woven applications for hot melts are in disposable articles such as diapers and sanitary napkins (see Fig. 22). These articles are made by high speed processes and are immediately packaged in sealed plastic bags, thus they are prime candidates for hot melt use. The applications are broken down into three categories, requiring three different types of adhesives construction, elastic attachment, and garment attachment. 

The construction adhesive is used to bond the layers of the non-woven article together. These layers consist of various non-woven materials and thin polyolefin... 

Functional adhesives provide the bonded product with a new or enhanced attribute. For example, adhesives now exist which promote the penetration of fluids into bonded non-woven products by virtue of their low contact angle with water [82]. These materials have been used successfully in both diapers and sanitary napkins for bonding the non-woven cover sheet to the absorbent core. Other examples are water absorbing adhesives that can act as wetness indicators by changing color [69] or can be bonded once moistened ]99]. Additional functionalities are currently underdevelopment. 

FUter medium The permeable portion of a filtration system that provides the liquid-solid separation, such as screens, papers, non-wovens, granular beds and other porous media. 

Non-woven A porous web or sheet produced by mechanically, chemically or thermally bonding together polymers, fibers or filaments. 

It was apparently helpful to add Hg" to the dil HNO3 used to roughen the surface of the animal hair employed in the making of felt which is a non-woven fabric of randomly oriented hairs. 

Glass-fiber tissue or non-woven fabrics are used for decorative purposes on many insulants. They also give improved strength to foam plastics and enhanced sound-absorption characteristics to mineral wools. 

The Li-SOCl2 battery consists of a lithium-metal foil anode, a porous carbon cathode, a porous non-woven glass or polymeric separator between them, and an electrolyte containing thionyl chloride and a soluble salt, usually lithium tetrachloro-aluminate. Thionyl chloride serves as both the cathode active material and the elec-... 

Regenerated cellulose membrane Regenerated cellulose membrane Regenerated cellulose membrane (silver-treated) Polyamide non-woven impregnated with regenerated cellulose... 

Rosato, D. V., Non-Woven Fibers in Reinforced Plastics, Ind. Engr. Chem., 54,8. 30-37, Sept. 1962. 

Fig. 7 Beschitin , a non-woven wound-dressing material manufactured from chitin by Unitika, Tokyo, Japan...

In relation to consumer uses of possible concern for this CICAD, data from the Women s Environmental Network indicate that butyltin stabilizers have been detected in the non-woven polypropylene topsheet of babies nappies (diapers). It is possible that this could relate to the last of the three key uses described above, in that the topsheet could be of silicone-grafted polypropylene (or, as discussed below, the butyltin may be present because of its use as a catalyst in the production of an antioxidant in polyolefin films). 

CHEMICAL RECYCLING OF NON-WOVEN POLYAMIDE LINING WASTE... 

We use the spinning process to make polymer fibers and filaments that can be converted into fabrics and cordage. During fiber spinning, molten polymer is pumped through holes in a plate to form a multiplicity of strands that are rapidly stretched and cooled. The finished product comprising oriented fibers is either wound up on spools or converted directly into a non-woven fabric. 

Non-woven fabrics can be produced very economically, which suits them for many singleuse health and hygiene applications, such as the outer cover and body contacting layers of... 

Polymer scientists and engineers have developed a wide variety of processes by which to convert polypropylene into useable articles. These processes include fiber-spinning, production of melt blown and spun bond non-woven fabrics, film production, blow molding, and injection molding. The following sections describe these processes and the resulting properties of the product as a function of the process. 

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