Disposal diapers

Acrylates are primarily used to prepare emulsion and solution polymers. The emulsion polymerization process provides high yields of polymers in a form suitable for a variety of appHcations. Acrylate polymer emulsions were first used as coatings for leather in the eady 1930s and have found wide utiHty as coatings, finishes, and binders for leather, textiles, and paper. Acrylate emulsions are used in the preparation of both interior and exterior paints, door poHshes, and adhesives. Solution polymers of acrylates, frequentiy with minor concentrations of other monomers, are employed in the preparation of industrial coatings. Polymers of acryHc acid can be used as superabsorbents in disposable diapers, as well as in formulation of superior, reduced-phosphate-level detergents. 

As binders for fiherfill and nonwovens, the emulsions are applied to a loose web or mat, then heated to form a film that sticks the loose fibers together. Polyester (188—191), glass (192), and rayon (193) mats are bonded in this manner for a variety of end uses including quilting, clothing, disposable diapers and towels, filters, and roofing (see Nonwoven fabrics). 

Such repositioning inevitably means reduced production volume, and for the first time this century production in the last decade has been below that a decade earUer (Eig. 9). Most capacity reductions have been in North America and especiaUy eastern Europe. This has been offset in part by capacity increases in the Ear East. Rayon is no longer a significant component of carpets, and has lost the disposable diaper coverstock business to cheaper and more easUy processed polypropylene. It has, however, gained share in health and hygiene products and is now a principal component of tampons worldwide. 

In the United States, fibers and injection mol ding are the main appHcations for polypropylene (Table 8), followed by film. In Europe and Japan, injection mol ding appHcations predominate (Table 10). This market area is more likely to decline in economic recession, as consumers postpone purchases of apphances and automobiles. Film appHcations are important in both regions, but fibers are a much less important use for polypropylene in Japan than in other developed regions. The heavy use of polypropylene nonwovens in the manufacture of disposable diapers and similar products, and the wide use of polypropylene carpets in the United States, account for the greater consumption of fibers. 

Disposable polypropylene nonwoven fabrics are widely used as the coverstock for disposable baby diapers. The expansion of the disposable diaper market throughout the world has been the primary source of growth in the consumption of polypropylene in the fiber market. In addition, nonwoven polypropylene fabrics are used in a variety of other disposable sanitary products, such as baby wipes, adult incontinence, and feminine hygiene products. Use of polypropylene nonwovens in disposable medical apparel, such as surgical gowns, has increased as a means of reducing the spread of infection. 

Etherification and esterification of hydroxyl groups produce derivatives, some of which are produced commercially. Derivatives may also be obtained by graft polymerization wherein free radicals, initiated on the starch backbone by ceric ion or irradiation, react with monomers such as vinyl or acrylyl derivatives. A number of such copolymers have been prepared and evaluated in extmsion processing (49). A starch—acrylonitrile graft copolymer has been patented (50) which rapidly absorbs many hundred times its weight in water and has potential appHcations in disposable diapers and medical suppHes. 

Poly(3-hydroxybutyrate—3-hydroxyvalerate) [80181 -31 -3] resin, produced from a bacterium during a sugar fermentation process, has been reported to be biodegradable, and its target markets include "flushables" such as feminine hygiene products and disposable diapers (99). 

Thermoplastic block copolymers were used for pressure-sensitive and hot-melt rubber adhesives as from the middle sixties. These adhesives found application in packaging, disposable diapers, labels and tapes, among other industrial markets. The formulation of these adhesives generally includes an elastomer (generally containing styrene endblocks and either isoprene, butadiene or ethylene-butylene midblocks) and a tackifier (mainly a rosin derivative or hydrocarbon resin). 

Lower-density E-plastomers have found alternate use in cast film processes to make elastic film laminates with good breathability which contain laminates of liquid impermeable extensible polymeric films with extensible-thermoplastic-polymer-fiber nonwovens and nonwoven webs of polyethylene-elastomer fibers as the intermediate layers. The development relates to a breathable film including an E-plastomer and filler that contributes to pore formation after fabrication and distension of the film. The method and extent of distension is designed to produce a breathable film by stretching the film to form micropores by separation of the film of the E-plastomer from the particulate solids. This film is useful for manufacture of absorbent personal-care articles, such as disposable diapers and sanitary napkins and medical garments. In detail, these constructions comprise a liquid impermeable extensible film comprising polyolefins. The outer layer contains extensible-thermoplastic-polymer-fiber nonwovens, and an elastic intermediate layer contains nonwoven webs of fiber E-plastomers. The intermediate layer is bonded to the film layer and the outer... 

Anionic polymerization of polystyrene takes place very rapidly- much faster than free radical polymerization. When practiced on a large scale, this gives rise to heat transfer problems and limits its commercial practice to special cases, such as block copolymerization by living reactions. We employ anionic polymerization to make tri-block copolymer rubbers such as polystyrene-polybutadiene-polystyrene. This type of synthetic rubber is widely used in the handles of power tools, the soft grips of pens, and the elastic side panels of disposable diapers. 

Another widespread use of polyurethane elastic fibers is in disposable diapers and adult incontinence garments. Elastic strands are incorporated into waistbands and side panels made of non-woven fabrics where they improve fit and reduce leakage. 

Meat and fish scraps Dog feces, used cat litter Disposable diapers Coal ashes... 

Polypropylene (PP) is used in a variety of areas, from snack food packaging to battery cases to disposable diaper linings. It is frequently interchanged for polyethylene or polystyrene. 

Table 9.10 shows the distribution of U.S. household incomes, which limits what each household can afford to buy. Let us consider baby diapers. A mother has a number of options to consider cloth diapers delivered to the home and retrieved after use, cloth diapers that are home laundered, disposable paper diapers for the garbage can after use, and the rural poor may let the babies run around with bare bottoms. The poor families buy less goods, and need to concentrate purchases on housing and basic food, such as bread and potatoes. The expenditure of 456 for disposal diapers in a budget of 75,000 is 0.6%, which is not a serious problem but for families with less than 10,000 income per year, this sum becomes 4.5%, which represents a much bigger burden, and less expensive and affordable options would be chosen. 

Extensive progress has been made in the technological applications of gels [1, 7, 8]. Disposable diapers and sanitary napkins use gels as super-water absorbents. Gel sheets have been developed to keep fish and meat fresh. Gels are... 

If you can wash cloth diapers at home using chlorine alternatives in a washing machine with really hot water, great. Your choice is made. This is an inexpensive (if time-consuming) way of dealing with the diapering dilemma. Sure, you ll use a lot of water, but so do the cloth diaper delivery services, and the manufacturers of disposable diapers. Just try to find diaper covers that aren t plastic or don t contain plastic, especially PVC. There are plenty of (sometimes organic) cotton and wool versions available. 

If you aren t set up to wash cloth diapers at home, conventional disposable diapers aren t a good option. One widely quoted study (published in Archives of Environmental Health and conducted by Anderson Laboratories back in 1999) found mice exposed to VOC chemicals emitted by conventional disposables had asthmalike reactions. They also contain chlorine and have high-tech chemical gel cores that activate when your baby pees to lock in moisture. The Children s Health Environmental Coalition says this absorbent material—sodium polyacrylate— could cause respiratory and skin irritations in occupational settings (where exposure is higher than with diaper use). We wonder how safe can that much chemical activity that close to a baby s genitals be twenty-four hours a day ... 

The other choice is to use environmentally friendly disposable diapers like Tushies. They re a cotton-blend diaper made with chlorine-free wood pulp that contains no chemicals or gels. (Some other brands of environmental disposables do use gel if you read the fine print.) Tushies can be found at Whole Foods,... 

Lactic acid is an important chemical that has wide applications in food, pharmaceutical, cosmetic, and chemical industries. There are increasing interests in production of lactate esters and biodegradable polylactic acid (PLA) from lactic acid. Lactate esters are a relatively new family of solvents with specific properties. They are considered safe and are biodegradable (1). In many situations they can replace toxic solvents. Their functions vary from that of intermediates in chemical reactions to solvents in ink formulations and cleaning applications (2). PLA has been widely used in medical implants, sutures, and drug-delivery systems because of its capacity to dissolve over time (3-5). PLA also can be used in products such as plant pots, disposable diapers, and textile fabrics. 

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