Polyvinyl chloride industrial applications

Worldwide, the increased usage of TPEs is occurring mainly as a substitution for conventional thermoset rubber. However, TPEs are also being used as substitutes for soft polyvinyl chloride (PVC) applications in the plastics industry. Due to the low cost of PVC this substitution can be difficult to justify. 

The development of electrical power made possible the electrochemical industry. Electrolysis of sodium chloride produces chlorine and either sodium hydroxide (from NaCl in solution) or metallic sodium (from NaCl fused). Sodium hydroxide has applications similar to sodium carbonate. The ad vantage of the electrolytic process is the production of chlorine which has many uses such as production of polyvinyl chloride. PVC, for plumbing, is produced in the largest quantity of any plastic. 

In a comprehensive study of trichloroethylene emission sources from industry conducted for EPA, the major source was degreasing operations, which eventually release most of the trichloroethylene used in this application to the atmosphere (EPA 1985e). Degreasing operations represented the largest source category of trichloroethylene emissions in 1983, accounting for about 91% of total trichloroethylene emissions. Other emission sources include relatively minor releases from trichloroethylene manufacture, manufacture of other chemicals (similar chlorinated hydrocarbons and polyvinyl chloride), and solvent evaporation losses from adhesives, paints, coatings, and miscellaneous uses. 

A vast number of polymer compounds are available commercially. Generally they are known by their polymer type in full or abbreviated (e.g., acrylic, polyvinyl chloride or PVC, high density polyethylene or HDPE), and frequently by a manufacturer s trade name. There is little standardisation into classes based on chemical composition or physical performance, as there is for metals. In reality, a particular chemical composition does not fully define the physical properties, while each class of performance properties can be met by a range of competing polymer types. The current trend is towards further diversification polymer compounds are increasingly being tailored to a particular application. Only in industries where recycling is an issue is there pressure for a more limited number of polymers, which can be identified and separated at the end of product life. 

A development of interest to the chemical industry is the tubular precipitator of reinforced-plastic construction (Wanner, Gas Cleaning Plant after T1O2 Rotary Kilns, technical bulletin, Lurgi Corp., Frankfurt, Germany, 1971). Tubes made of polyvinyl chloride plastic are reinforced on the outside with polyester-fiber glass. The use of modem economical materials of construction to replace high-maintenance materials such as lead has been long awaited for corrosive applications. 

In this section we demonstrate the performance of the proposed model on an industrial-scale case study. Instead of considering the full scale petrochemical network which may have limited application, we consider a special case of the integration problem. Although the proposed formulation covers the full scale refinery network and petrochemical systems, the case study will consider the integration of a petrochemical complex for the production of polyvinyl chloride (PVC) with a multi-refinery network. PVC is one of the major ethylene derivatives that has many important applications and uses, including pipe fittings, automobile bumpers, toys, bottles and many others (Rudd et al., 1981). 

Chlorine (from the Greek chloros for yellow-green ) is the most abundant halogen (0.19 w% of the earth s crust) and plays a key role in chemical processes. The chlor-alkali industry has been in operation since the 1890s and improvements in the technology are still important and noticeable, for example, the transition from the mercury-based technology to membrane cells [60]. Most chlorine produced today is used for the manufacture of polyvinyl chloride, chloroprene, chlorinated hydrocarbons, propylene oxide, in the pulp and paper industry, in water treatment, and in disinfection processes [61]. A summary of typical redox states of chlorine, standard potentials for acidic aqueous media, and applications is given in Scheme 2. 

These fatty acids and oils, as well as their derivatives, are applied in a broad range of products such as surfactants, lubricants and coatings, and, obviously, biodiesel. Upon epoxidation of the double bonds of the unsaturated fatty acids, very important compounds for the polymer industry are produced, which are used as plasticizers and stabilizers for a broad range of polymers such as polyvinyl chloride (PVC), polyesters, and polyurethanes [71]. Another interesting application has been found in the conversion of epoxidized soybean oil to carbonated soybean oil that can be reacted with ethylene diamine to obtain a polyurethane with interesting properties [72], Traditionally, stoichiometric reagents are used for the epoxidation of these oils and fats, albeit in some cases, with limited results. Therefore, the MTO/H2O2 system has been explored to epoxidize unsaturated fatty acids and oils. 

The key industrial applications and markets for normal and isobutanol and 2-ethylhexanol are discussed. As will be noted, the C4 oxo alcohols find use primarily within the coatings industry, either as solvents, per se, or as intermediates to manufacture solvents or protective coatings chemicals. Applications for 2-ethylhexanol, while numerous and varied, are basically oriented toward the manufacture of plasticizers for polyvinyl chloride. Total U.S. consumption of these alcohols in 1979 was approximately 1.3 billion pounds -730 million pounds of n-butanol, 190 million pounds of isobutanol, and 380 million pounds of 2-ethylhexanol. The consumption pattern is summarized in Table II and described in the following sections ... 

The ability of vinyl chloride to polymerize was first observed over 150 years ago. Polyvinyl chloride has been industrially manufactured since approximately 1930. Even though pure PVC is fairly unstable, it is ranked second after PE for bulk plastic production. The manifold applications of PVC are made possible by the discovery of effective stabilizers and other additives for the polymer. 

Cadmium is found in low concentrations in most soils and waters. It is produced as a by-product of zinc and lead mining and smeltering. Industrial use of cadmium has led to a dramatic increase in environmental problems caused by this element. Cadmium is used in semiconductors, nickel-cadmium batteries, electroplating, polyvinyl chloride (PVC) manufacturing, and control rods for nuclear reactors. The most important sources for aquatic contamination are active and inactive lead-zinc mines, land application of sewage sludge, zinc-cadmium smelters, effluents from plastic and steel production, and wastewaters from the production of nickel-cadmium batteries and electroplating (Zuiderveen, 1994). 

At times, low- or high-intensity blending alone can produce a suitable product for use by the fabricator. An example of this would be a polyvinyl chloride (PVC) blend used for several large-volume extrusion applications. More frequently, however, a compounding process is required to obtain the desired physical property. The five primary compounding processes used in the industry for controlling the above parameters are single-screw extrusion (SSE), twin-screw extrusion (TSE), continuous mixers, batch mixers, and kneaders. Table 18.1 summarizes key aspects of each process. 

Post-chlorinated polyvinyl chloride (cPVC) is a material which offers a combination of mechanical strength, temperature and corrosion resistance and low installation costs, that meets a variety of process uses. This comprehensive article describes cPVC s key properties in detail and highlights the various industries and applications for the polymer, particularly pipes and fittings. 

Cd and its compounds find applications in several industrial materials electrode materials in Ni-Cd batteries (about 70% of total produced Cd), pigments in ceramics, glasses, paper, plastics, artists colors (13%), stabilizers for polyvinyl chloride and related polymers (7%), coatings on steel, aluminium, and other nonferrous metals (8%), and specialized alloys (see Alloys) and others (2%). 

Use Solvent for resins, acetylene, etc., pigment dispersant, petroleum processing, spinning agent for polyvinyl chloride, microelectronics industry plastic solvent applications, intermediate. 

Today Industry makes available a host of excellent chemical resistant plastics for a multitude of applications. This paper will discuss fabricated polyethylene, polyvinyl chloride and polypropylene for specific industrial applications. 

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