Manufacturing of polymers

Styrene is manufactured by alkylating benzene with ethene followed by dehydrogenation, or from petroleum reformate coproduction with propylene oxide. Styrene is used almost exclusively for the manufacture of polymers, of which the most important are polystyrene, ABS plastics and styrene-butadiene rubber. U.S. production 1980 3 megatonnes. 

Vinyl chloride is used almost exclusively for the manufacture of polymers and copolymers. U.S. production 1983 2-6 megatonnes. See vinyl chloride polymers. 

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

Commercial styrene is used almost entirely for the manufacture of polymers. Polystyrene accounts for 64% of the worldwide demand for styrene. The rest is for manufacture of copolymers ABS, 9% SB latex, 7% UPR, 5% SBR, 4% others, 11%. 

Acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, ethyl acetate, and tetrahydrofuran are solvents for vinyhdene chloride polymers used in lacquer coatings methyl ethyl ketone and tetrahydrofuran are most extensively employed. Toluene is used as a diluent for either. Lacquers prepared at 10—20 wt % polymer sohds in a solvent blend of two parts ketone and one part toluene have a viscosity of 20—1000 mPa-s (=cP). Lacquers can be prepared from polymers of very high vinyhdene chloride content in tetrahydrofuran—toluene mixtures and stored at room temperature. Methyl ethyl ketone lacquers must be prepared and maintained at 60—70°C or the lacquer forms a sohd gel. It is critical in the manufacture of polymers for a lacquer apphcation to maintain a fairly narrow compositional distribution in the polymer to achieve good dissolution properties. 

Among the butylenes, isobutylene has become one of the important starting materials for the manufacture of polymers and chemicals. There are ... 

With the exception of use in the manufacture of polymers, markets for chlorobenzenes are mature, and demand is expected to show Htde if any growth in the next few years. 

One unusual but nevertheless important application of SAN has been in the manufacture of polymer polyols used in the manufacture of flexible polyurethane foams. Proportions of up to 40% of the polyol may be used to increase stiffness as foam bulk densities are lowered (see Section 27.5.4). 

Represents more than 400 manufacturers of polymers, additives, and machinery as well as all types of plastics processors and fabricators. Membership is divided into 15 Business Groups sharing four Market Sector Groups. 

Conjugated dienes are among the most significant building blocks both in laboratories and in the chemical industry [1], Especially, 1,3-butadiene and isoprene are key feedstocks for the manufacture of polymers and fine chemicals. Since the discovery of the Ziegler-Natta catalyst for the polymerizations of ethylene and propylene, the powerful features of transition metal catalysis has been widely recognized, and studies in this field have been pursued very actively [2-7]. 

Most of the plastics and synthetic polymers that are used worldwide are produced from petrochemicals. Replacing petroleum-based feedstocks with materials derived from renewable resources is an attractive prospect for manufacturers of polymers and plastics, since the production of such polymers does not depend on the limited supply of fossil fuels [16]. Furthermore, synthetic materials are very persistent in the environment long after their intended use, and as a result their total volume in landfills is giving rise to serious waste management problems. In 1992,20% of the volume and 8% of the weight of landfills in the US were plastic materials, while the annual disposal of plastics both in the US and EC has risen to over 10 million tons [17]. Because of the biodegradability of PHAs, they would be mostly composted and as such would be very valuable in reducing the amount of plastic waste. 

The technique is currently not used as widely as UV, visible and infrared spectrometry partly due to the high cost of instrumentation. However, it is a powerful technique for the characterization of a wide range of natural products, raw materials, intermediates and manufactured items especially if used in conjunction with other spectrometric methods. Its ability to identify major molecular structural features is useful in following synthetic routes and to help establish the nature of competitive products, especially for manufacturers of polymers, paints, organic chemicals and pharmaceuticals. An important clinical application is NMR imaging where a three-dimensional picture of the whole or parts of a patient s body can be built up through the accumulation of proton spectra recorded over many different angles. The technique involves costly instrumentation but is preferable to... 

Vinyl chloride monomer (VCM) is the main substrate for the manufacture of polymers used as packaging materials for food. Since VCM is considered by lARC to be a human carcinogen, monomer levels in PVC food packaging materials are strictly controlled. To ensure a safe product, the residual content of VCM in the finished material or article is limited to one mg per kg in the final product (Council Directive 78/142/EEC). Furthermore, VCM should not be detectable in foodstuflfs. Commission Directives 80/766/EEC and 81/432/ EEC give the method of analysis for official control of the VCM level in food packaging materials and in foods - gas-phase chromatography using the headspace method, after dissolution or suspension of samples in N,N-dimethylacetamide. Both residual monomer content of the polymer and... 

The formaldehyde process is an air oxidation of methanol, CH3OH, which has water as a by-product. Formaldehyde is a gas at room temperature, but is usually handled either as a water solution called formalin or as polymers called paraformaldehyde and trioxane. Both are readily converted back ro formaldehyde. Some uses of formaldehyde are the manufacture of polymer resins and as a germicide. 

Hydroxymethylfurfural (HMF) can be readily obtained from acid-catalysed dehydration of carbohydrates. On the other hand, FFA can be further reacted to produce 2,5-furandiacetic acid and 5-carboxyfuran-2-acetic acid which could form polymers, much like tereftahc acid. Therefore the carbonylation of MF can be regarded as the first step of the green manufacture of polymers on the basis of renewable (carbohydrate) raw materials. 

Chlorinated ethanes and ethylenes comprise ethyl chloride, ethylene dichloride (1,2 dichloroethane), vinyl chloride, trichloroethylene (TCE), perchloroethylene (RCE), and several CFCs. Some of the major uses of these compounds are as degreasing agents, dry-cleaning solvents, building blocks for manufacturing of polymers (e.g., RVC, ethyl cellulose), and raw material for the production of tetraethyl lead and CECs. We discuss ethylene dichloride, trichloroethylene, and perchloroethylene as examples of this group. 

Uses. Manufacture of polymers and resins for textiles, paints, and leather finishes... 

Provder, T. 2006. Film Formation, Process, and Morphology. Oxford University Press, New York. Rudin, A. 1998. Elements of Polymer Science and Technology, 2nd ed. Academic, Orlando, EL. Shibaev, V. and Lam, L. 1993. Liquid Crystalline and Mesomorphic Polymers. Springer, New York. Sinha, R. 2002. Outlines of Polymer Technology Manufacture of Polymers and Processing Polymers. Prentice-Hall, Englewood Clifts, NJ. 

HCFC-22 chcif2 Industrial refrigerant, manufacturing of polymers, polystyrene foams, aerosol sprays... 

Some of its salts are also explosive, for example, Hg(CN)2 and Hg(CN)2 HgO. Its methyl salt is explosive when in the CH3NC form, while the CH3CN form is not an explosive HCN is used in the manufacture of polymers fumigants (Ref 14)... 

At present DDT finds limited use only in certain developing countries since other insecticides are considerably more expensive [18], although some industrial countries, too, reportedly use it for the control of synanthropous insects [18, 19]. The existing manufacturing capacity for DDT and chloral remains quite high and so a search for alternative uses of these chemicals is worthwhile. One approach is to use these substances as starting materials for the manufacture of polymers with desired properties. 

Among the butylenes, isobutylene has become one of the important starting materials for the manufacture of polymers and chemicals. There are many patents that describe the use of isobutylene or its derivatives to produce insecticides, antioxidants, elastomers, additives for lubricating oils, adhesives, sealants, and caulking compounds. Table 9 shows the use pattern of butylenes in the United States. 

Mercaptans are important industrial compounds used in the agrochemical (thiocarbamates, phosphorothioates), pharmaceutical and cosmetic industries as well as in the manufacture of polymers. The main aspects of their industrial syntheses and uses have been reviewed by a specialist in this field [13]. 

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