Rubber-plastic alloys

The three major types of TPEs are block copolymers such as SEES (styrene-ethylene-butylene-styrene block copolymer) (Kraton by Kraton Polymer), polyether— polyester (Hytrel by DuPont), rubber/plasticblends (900 series Sumitomo Chemical), and dynamically vulcanized rubber/plastic alloys (Innoprene by Kumho Polychem, Santo prene by Exxon-Mobil, Sarlink by DSM, Unipene byTeknor Apex). Figure 3.28 shows the cost versus general performance comparison for different TPEs [31]. 

The shell may be of metal (steel, alloy, or non-ferrous), plastic, wood or some combination which may require the addition of liners or inner layers of rubber, plastic or brick. The mechanical problems of attaching inner nozzles, supports and brick require considerable attention that is not an integral part of sizing the equipment. Figures 9-2A-C show a typical large steel brick-lined-membrane lined tower with corbeled brick support locations. In these towers, temperature and/or corrosive conditions usually dictate the internal lining, and the selection of the proper acid- (or alkali-) proof cements. 

Blends and Elastomeric Alloys 5.4.2.1 Elastomeric Rubber-Plastic Blends... 

Rader C.P. and Abdou Sabet S., Two phase elastomeric alloys. Thermoplastic Elastomers from Rubber Plastic Blends (De S.K. and Bhowmick, A.K., eds.), Ellis Horwood, London, 1990, 159. 

Lead has a low melting point (326°C). It is a soft, malleable metal, i.e., it can be easily formed into a variety of shapes. It can form alloys with many other metals. Other important industrial products containing Pb include pipes, paints, solders, glass, pottery glazes, rubber, plastics, and insecticides. 

Brasses and bronzes, iron-base alloys, nickel, monel, magnesium alloys, hard rubber, plastics, tin, aluminum, and like metals must be added to ordinary gray and white cast iron as materials for pump construction. Practically any alloy or modern metal can be fabricated into pumps, and it remains only for the chemical engineer to stipulate the kind of solution he wishes to handle, or the kind of metal, and the pump manufacturer will attempt to construct a pump for the service demanded. (See Perry s Chemical Engineers Handbook, 3d ed., p. 1424.)... 

Plastic/Plastic and Plastic/Rubber blends alloys... 

Half of all the antimony consumption in the United States is used to make flame retardants used in rubber, plastics, coatings, and so on. Another large application for antimony is to form an alloy with lead, to harden the lead for use in car batteries. 

Spirals have been manufactured from concrete, plastics, solid rubber, iron, and special iron alloys. 

Blend of (1) and (2) type categories mostly include the modification of engineering thermoplastics with another thermoplastic or rubber. PS-EPDM blends using a low-molecular weight compound (catalyst) Lewis acid have been developed [126]. Plastic-plastic blends, alloys of industrial importance, thermoplastic elastomers made by dynamic vulcanization, and rubber-rubber blends are produced by this method. 

In general, just about any material that can be worked into the impeller design is available, including steel, stainless alloys, copper alloys, nickel and alloys, hard rubber, and lead, rubber and plastic coatings on impellers and shafts. 

For corrosive service the wheel can be made of stainless or nonferrous alloys can be all plastic in some designs or may be covered with rubber, lead, or plastic. Rubber-covered fans are usually limited in wheel peripheral velocity to 12,000-15,000 ft/min, although some wheels with certain types of rubber can run higher. ... 

Hence whilst in the past corrosion control has involved, in the main, the use of metal alloys, protective coatings, inhibitors, etc. corrosion problems may now often be circumvented by the use of self-supporting organic polymers in the form of either rubbers or plastics. It must however be immediately stressed that such materials are not invariably inert to chemicals and they display their own particular response to such materials. A consideration of such behaviour will be a prior object of this section. 

Styrene maleic anhydride SMA is a copolymer made with or without rubber modifiers. They are sometimes alloyed with ABS and offer good heat resistance, high impact strength and gloss but with little appreciable improvement in weatherability or chemical resistance over other styrene based plastics. 

Uses Plasticizer for cellulose resins moth repellant camphor substitute in cellulose solvent manufacturing of smoke candles and explosives rubber vulcanization accelerator insecticide refining aluminum alloys. 

Uses. Constituent of alloys with other metals (tin, lead, copper) sulfides used in compounding of rubber and manufacture of pyrotechnics trioxide used as a fire retardant in plastics, rubbers, textiles, and paints chlorides used as coloring agents and as catalysts fluorides used in organic synthesis and pottery manufacmre... 

Chemical pumps are available in a variety of materials. Metal pumps are the most widely used. Although they may be obtained in iron, bronze, and iron with bronze fittings, an increasing number of pumps of ductile-iron, steel, and nickel alloys are being used. Pumps are also available in glass, glass-lined iron, carbon, rubber, rubber-lined metal, ceramics, and a variety of plastics, such units usually being employed for special purposes. 

Materials which are usually extruded include some soft metals (lead, dn, copper, brass, aluminum, magnesium and various alloys) rubber, soaps, ceramics, foods, plastics, Dynamites, Explosives (like Amatol... 

Compared to carbon, the related element silicon is relatively unimportant, so far as uses for the uncombined element are concerned. Most of the silicon produced commercially is used in the metallurgical and glass industries. In metallurgy, it is ued in the manufacture of a useful iron-silicon alloy known as ferrosilicon. Silicon is also used as an additive in organic products such as plastic and rubber compounds, and elemental silicon is a fundamental material in semiconductor and microprocessor manufacturing. 

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