Polymer product categories

Adhesive Transfer Processes. Many polymers, whether dehberately or accidentally, are adhesives, so that much of the adhesive industry can be regarded as a part of the mbber and plastics industry. However, there are several important material-transfer appHcations involving polymer products that are so critically dependent on controlled adhesion that they merit specific mention in that category. They include hot stamping foils, release coatings for pressure-sensitive adhesive products, photocopier materials, transfer coatings, and transfer printing of textiles. 

Quite often, a vendor will not promote a product on the basis of a particular inhibitor category but rather, may promote the benefit of an individual component within the product (such as the ability of a constituent polymer to control soluble iron) and across product categories. So, a range of products within different categories, may therefore be marketed under a particular brand name that is common to all inhibitors containing the same iron polymer. 

In the chemical products sector bio-based raw materials are the only renewable alternative to replace fossil carbon sources. In some chemical product categories like, for example, detergents, renewable resources already make up a large share of the raw materials used due to their superior suitability and functionality. In the major chemical product category (with respect to the annually produced amount) of plastics, however, renewable resources still play a very small role. Nonetheless, steadily increasing numbers of bio-based polymers and products have been developed in recent years. The number of scientific papers on this topic is still growing rapidly while it remains at a constant level for traditional fossil-based polymeric materials. 

PHAs have frequently been championed as a solution to sustainable polymer production. This is because they can be produced from renewable raw materials and are biodegradable upon disposal. However, an inventory of materials and energy required to produce these polymers reveals a rather discouraging picture. In most categories quantifying environmental impact (land use, resource depletion and emissions to air and water) PHA production by fermentation scores worse than conventional petrochemical polymer production. 

This chapter has described the apphcation of HTPBs in fuel and solar cells as well as in aerospace. The three categories of HTP constitute but a small portion of the total polymer production, namely commodity, engineering, specialty and ultra categories, 95.29,4.5,0.2 and 0.01 wt%, respectively. By adjusting the molecular parameters and incorporating suitable additives, the commercial polymers may be formulated for a variety of other applications. 

The second category of polymerization reactions does not involve a chain reaction and is divided into two groups poly addition and poly condensation [4]. In botli reactions, tire growth of a polymer chains proceeds by reactions between molecules of all degrees of polymerization. In polycondensations a low-molecular-weight product L is eliminated, while polyadditions occur witliout elimination ... 

Chemical Manufacturing. Chemical manufacturing accounts for over 50% of all U.S. caustic soda demand. It is used primarily for pH control, neutralization, off-gas scmbbing, and as a catalyst. About 50% of the total demand in this category, or approximately 25% of overall U.S. consumption, is used in the manufacture of organic intermediates, polymers, and end products. The majority of caustic soda required here is for the production of propylene oxide, polycarbonate resin, epoxies, synthetic fibers, and surface-active agents (6). 

Protective Coatings. Some flame retardants function by forming a protective Hquid or char barrier. These minimize transpiration of polymer degradation products to the flame front and/or act as an insulating layer to reduce the heat transfer from the flame to the polymer. Phosphoms compounds that decompose to give phosphoric acid and intumescent systems are examples of this category (see Flame retardants, phosphorus flame retardants). 

Light-Duty Recreational Surfaces. Artificial surfaces intended for incidental recreational use, eg, swimming pool decks, patios, and landscaping, are designed primarily to provide a practical, durable, and attractive surface. Minimum cost is a prime consideration and has driven the quaUty of some such products to a low level. Most surfaces in this category utilize polypropylene ribbon and a tufted fabric constmction (see Olefin polymers, polypropylene). ... 

Properties. HydroxyethjIceUulose [9004-62-0] (HEC), is a nonionic polymer. Low hydroxyethyl substitutions (MS = 0.05-0.5) yield products that are soluble only in aqueous alkali. Higher substitutions (MS > 1.5) produce water-soluble HEC. The bulk of commercial HEC falls into the latter category. Water-soluble HEC is widely used because of its broad compatibiUty with cations and the lack of a solution gel or precipitation point in water up to the boiling point. The MS of commercial HEC varies from about 1.8 to 3.5. The products are soluble in hot and cold water but insoluble in hydrocarbon solvents. HEC swells or becomes pardy to mosdy soluble in select polar solvents, usually those that are miscible with water. 

A final category of encapsulating materials consists of reaction products of the nucleus material and a reagent. For example, pellets of nitronium perchlorate have been encapsulated in shells of the less reactive amm perchlorate (AP) by exposing the pellets to ammonia gas. The fragile AP shells were usually further protected by a top-coating of A1 or a polymer film (Ref 2). The most familiar example of this process is the natural one wherein A1 powders (or articles) become coated with a protective coating of A1 oxide thru exposure to atmospheric air... 

Determination of die mechanical properties of a cured polymer serves to characterize its macroscopic (bulk) features such as flexibility and hardness. Using standardized methods of the American Society for Testing and Materials (ASTM) and die International Standards Organization (ISO) allows direct comparison to otiier materials. The vast majority of polyurethane research and development is conducted in industry where mechanical properties are of vital importance because tins information is used to design, evaluate, and market products. General test categories are presented here with a few illustrative examples. 

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