Polymers, synthetic products made from

Polymers are very large organic molecules that are either made synthetically or are of natural origin, and find use as plastics, rubber, fibers, and coatings. Polymers were first produced commercially in 1860 by modification of cellulose from wood or cotton, followed by a fully synthetic product made from phenol and formaldehyde in 1910. 

This article discusses traditional hull ding and construction products, ie, not made from synthetic polymers (see Building materials, plastic), including wood, asphalt, gypsum, glass products, Pordand cement, and bricks. The article presents information about each basic material, the products made from it, the basic processes by which the products or materials are produced, estimates of the quantity or doUar value of the quantities produced or used in the United States, and some pertinent chemical or physical properties related to the material. More detailed chemical and physical property data can be found in articles devoted to the individual materials (see Asphalt Cement Glass Wood). 

Although thousands of different synthetic polymers have now been prepared, six compounds, called the Big Six, account for 76% of the synthetic polymers produced in the United States each year. Each polymer is assigned a recycling code (1-6) that indicates its ease of recycling the lower the number, the easier to recycle. Table 30.1 lists these six most common polymers, vas well as the type of products made from each recycled polymer. 

More and more products made from synthetic materials substituting for leather have been introduced into the market. S ynthetic leather substitutes are usually nonwoven fabrics coated or laminated with some kind of polymer. It is very often desired to identify if a product is a genuine leather or a synthetic substitute. The following four test methods can be used to identify the samples. 

The plastics industry and all the products made from plastics are almost entirely dependent on chemicals extracted or produced from hydrocarbons. This includes not only the familiar materials such as polyethylene, polypropylene, polyvinyl chloride (PVC), epoxies, nylon, polyesters, polycarbonate. Teflon and Plexiglas, but also includes a large portion of materials made from rubber and a diverse group of other materials formulated from polymers such as tape, glue, ink, waterproofing, wax, and polishes. Virtually all the synthetic fibers used in textile products, Orion , Dacron , Nylon and polyesters are made from polymers based on hydrocarbons. 

Viscose fibres are man-made fibres from natural ceUulosic resources they are thus biodegradable and have the same health and safety properties as natural ceUulosic properties, and are widely used in food, medical, healthcare, and hygiene products. In contrast to many synthetic fibres made from thermoplastic polymers, one advantage... 

The numerous industrial and consumer products made from olefins include many polymers and copolymers, synthetic rubbers [10, 11], plasticizers, surfactants, lube oil additives, synthetic lubricants, chemicals for oil field and fiber industry appUeations,... 

Some important everyday items that are made from polymers with widely different properties Include billiard balls, plastic dishes, soda bottles, barrier and decorative films, egg cartons, polymeric drinking glasses, foam seats, and automotive tires. These applications for synthetic polymers have developed over about 150 years. As shown in Table 2.1, modern polymer material science and technology can be traced back to as early as 1770 [1]. Some Important advances In the understanding of polymer production were developed before World War II. 

The expansion in technology has in turn encouraged research scientists to broaden the scope of their research. Notable advances have been made in such special fields as plastics, polymers, rubber, detergents, and many other synthetic products from petroleum. A number of these items represent broad technological achievements in their own right. Research has also made major contributions to the discovery, production, and transportation of petroleum. 

Because of the wide diversity in PUF manufacturing processes and likely contaminant chemistry, users are cautioned that sorbent quality control is more critical than with other synthetic polymers such as the Amberlite XAD series. Every effort should be made to procure PUF products consistently from the same manufacturer, preferably in each instance from the same production lot. Moreover, because of inconsistencies in manufacturing practices, first-time foam users should solicit the advice of other satisfied and experienced users in the selection of a sorbent supplier. 

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