Production world, polyurethane chemicals

Today, nitric acid is one of the 15 largest commodity chemicals with an armual world production of about 55 million tonnes (Uhde, 2005). Approximately 80% is used as an intermediate in the production of nitrogeneous fertilizers, primarily ammonium nitrate (NH4NO3). The remainder (20%) goes into the production of various chemicals such as explosives [trinitrotoluene, C6H2(N02)3CH3] or of intermediates for polymers like caprolactam, adipic add (for polyamides), or dinitroto-luene (for polyurethane). 

In 2002, the world production of polymers (not including synthetic libers and rubbers) was ca. 190 million metric tons. Of these, the combined production of poly(ethylene terephthalate), low- and high-density polyethyelene, polypropylene, poly(vinyl chloride), polystyrene, and polyurethane was 152.3 milhon metric tons [1]. These synthetic, petroleum-based polymers are used, inter alia, as engineering plastics, for packing, in the construction-, car-, truck- and food-industry. They are chemically very stable, and can be processed by injection molding, and by extrusion from the melt in a variety of forms. These attractive features, however, are associated with two main problems ... 

In recent years, we have become integrated into the much larger world of polyurethanes, but we have always begun our investigations with a focus on the surface chemistry. While our studies have been on the full range of polyurethane chemistries and the full range in which polyurethanes are produced, the chemical aspects in which we are most interested are foams (the bulk of polyurethane production), specifically open-celled foams, and more specifically products known in the industry as reticulated foams. 

These two examples show that a polyurethane — the reaction product of a polyol and an isocyanate — can serve in both geometric and chemical functions. This is essentially the theme of this book. Most polyurethanes are used for purposes other than the applications cited above. The true place of polyurethanes in the world today is based on the physical properties of the chemistry. What we hope to do is describe the polymer as a chemistry product with properties that are of use to scientists of various disciplines. 

Rigid foams are used for structural and insulation uses while the flexible materials are used for a vast variety of applications as seen in Figure 2.20. The versatility of polyurethane positions the product as unique in fire polymer world because of the breadth of applications. As we will show, small changes in chemistry can achieve a broad range of physical properties. This statement emphasizes the physical properties and serves as a testament, however, to the lack of chemical interest. It is supported by a description of the independent variables of density and stiffness and the range of products based on the primary attributes of polyurethanes. See Figure 2.21. 

Phosgene is an important intermediate in the manufacture of polycarbonate and polyurethane. U.S. 6,500,984 (to General Electric) describes a process for phosgene using carbon and silicon carbide catalysts. U.S. 6,054,104 (to DuPont) describes a process using a silicon carbide catalyst. U.S. 4,231,959 (to Stauffer Chemical) describes a process with recycle of unconverted CO. Estimate the cost of production for a world-scale plant. Which catalyst or combination of catalysts would you recommend ... 

The major uses of aniline are in the manufacture of polymers, mbber, agriculmral chemicals, dyes and pigments, pharmaceuticals, and photographic chemicals. Approximately 67% of the world production of aniline is used in the manufacmre of rigid polyurethanes and reaction-injection-molded (RIM) parts for the constmction, automotive, and durable goods industries. 

Propene oxide (PO, lUPAC nomenclature 2-methyloxirane) is an important chemical feedstock, having a world annual production capacity of about 7 mUhon tons [1]. It is processed into the major products, polyurethane polyols and propylene glycol [2]. The former are used in the manufacture of polyurethane foams and the latter for antifreeze (safer than ethylene glycol), drugs, cosmetics etc. 

Carbonyl chloride (phosgene), 14.11, is a highly toxic, colourless gas (bp 281 K) with a choking smell, and was used in World War I chemical warfare. It is manufactured by reaction 14.50, and is used industrially in the production of diisocyanates (for polyurethane pol5mers), polycarbonates and 1-naphthyl-A -methylcarbamate, 14.12 (for insecticides). 

In 2011, San Diego-based Genomatica demonstrated industrial-scale microbial production from glucose of 1,4-butanediol, an organic alcohol used around the world in quantities of about 1 million metric tons per year as a solvent and in the manufacture of plastics, polyurethane, polyesters, tetrahydrofuran, and other materials. The conventional chemical synthesis of... 

Phosgene is a very important chemical intermediate. It is used to make the isocyanate monomers that go into products such as polyurethane foams and coatings. It also is used to make polycarbonate polymers. However, it is extremely toxic, so much so that it was used as a chemical warfare agent during World War I. ... 

By the end of the 19th century, important advances in the area of cellulose chemistry led to the development of chemical fibers from natural polymers. A first major step was the development of artificial silk made from nitrocellulose by Count Hilaire de Chardonnet and presented at the world exhibition in Paris in 1894. Alas, some unfortunate women wearing his new garments went up in flames when they accidentally came to close to open fire because nitrocellulose also makes an excellent explosive. Despite these initial difficulties, other inventions in the early 20th century in macromolecular chemistry, namely viscose production by Urban, Frem-ery, and Bronnert in 1901 and the discovery of macromolecules by H. Staudinger, initiated the development of chemical fibers from synthetic polymers, such as polyamide (PA), polyester (PES), polyacrylonitrile (PAN), and polyurethane (PUR). It took another 60 years until in 1993, the overall production of man-made fibers for the first time exceeded that of natural fibers. 

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