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Polyethylene metals

Guns are used to apply cartridges of sealants (polyurethanes, silicones) and also adhesives in mastics form such as polychloroprene or MS polymer mastics. The cartridges are made of plastic (polyethylene), metal or cardboard, the bottom of the cartridge is a piston, so that when the trigger of the gun is actuated the piston will push the sealant to extrude it through a tip cut to the proper diameter (Fig. 11). [Pg.71]

Between two different semi constraint and unconstraint elbow prosthesis, Semi constrained prosthesis has a polyethylene-metal loose-hinged device with intrinsic stability. Although this stability prevents bones unfavorable dislocation, but it permit to valgus-varus motion. As it is reported in literature, loosening and mechanical failure can be considered as the most complication for linked prosthesis [6,7]. [Pg.215]

Ethyl indole-2-carboxylate (45.2 g, 0.238 mmol) was dissolved in abs. EtOH (450 ml) in a 11 polyethylene container and cooled in a dry icc-cthanol bath. The solution was saturated with dry HCl gas until the volume increased to 875 ml, Granular tin metal (84.2g, 0.7l0mmol) was added to the slurry and... [Pg.145]

Ziegler found that adding certain metals or their compounds to the reaction mixture led to the formation of ethylene oligomers with 6-18 carbons but others promoted the for matron of very long carbon chains giving polyethylene Both were major discoveries The 6-18 carbon ethylene oligomers constitute a class of industrial organic chemicals known as linear a olefins that are produced at a rate of 3 X 10 pounds/year m the... [Pg.610]

The acryhc esters may be stored in mild or stainless steel, or aluminum. However, acryhc acid is corrosive to many metals and can be stored only in glass, stainless steel, alurninum, or polyethylene-lined equipment. Stainless steel types 316 and 304 are preferred materials for acryhc acid. [Pg.157]

The actuator contains the final orifice and a finger pad or mechanical linkage for on—off control. The spray pattern is largely affected by the constmction of the actuator, particularly by the chamber preceding the orifice. Actuators are often termed mechanical breakup and nonmechanical breakup depending upon the complexity of this chamber. Mechanical breakup actuators are of more expensive two-piece constmction. Actuators are usually molded from polyethylene or polypropylene the breakup insert may be almost any material, including metal. [Pg.350]

Corrosion. Ammonium bifluoride dissolves in aqueous solutions to yield the acidic bifluoride ion the pH of a 5% solution is 3.5. In most cases, NH4HF2 solutions react readily with surface oxide coatings on metals thus NH4HF2 is used in pickling solutions (see Metal surface treatments). Many plastics, such as polyethylene, polypropylene, unplasticized PVC, and carbon brick, are resistant to attack by ammonium bifluoride. [Pg.148]

In some cases, particularly with iaactive metals, electrolytic cells are the primary method of manufacture of the fluoroborate solution. The manufacture of Sn, Pb, Cu, and Ni fluoroborates by electrolytic dissolution (87,88) is patented. A typical cell for continous production consists of a polyethylene-lined tank with tin anodes at the bottom and a mercury pool (ia a porous basket) cathode near the top (88). Pluoroboric acid is added to the cell and electrolysis is begun. As tin fluoroborate is generated, differences ia specific gravity cause the product to layer at the bottom of the cell. When the desired concentration is reached ia this layer, the heavy solution is drawn from the bottom and fresh HBP is added to the top of the cell continuously. The direct reaction of tin with HBP is slow but can be accelerated by passiag air or oxygen through the solution (89). The stannic fluoroborate is reduced by reaction with mossy tin under an iaert atmosphere. In earlier procedures, HBP reacted with hydrated stannous oxide. [Pg.168]

Titanium tetrafluoride may be prepared by the action of elemental fluorine on titanium metal at 250°C (5) or on Ti02 at 350°C. The most economical and convenient method is the action of Hquid anhydrous HF on commercially available titanium tetrachloride in Teflon or Kynar containers. Polyethylene reacts with TiCl and turns dark upon prolonged exposure. The excess of HF used is boiled off to remove residual chloride present in the intermediates. [Pg.255]

Structural Components. In most appHcations stmctural foam parts are used as direct replacements for wood, metals, or soHd plastics and find wide acceptance in appHances, automobUes, furniture, materials-handling equipment, and in constmction. Use in the huil ding and constmction industry account for more than one-half of the total volume of stmctural foam appHcations. High impact polystyrene is the most widely used stmctural foam, foUowed by polypropylene, high density polyethylene, and poly(vinyl chloride). The constmction industry offers the greatest growth potential for ceUular plastics. [Pg.416]

In unalloyed steel containers formamide discolors slowly during shipment and storage. Both copper and brass are also subject to corrosion, particularly in the presence of water. Lead is less readily attacked. Aluminum and stainless steel are resistant to attack by formamide and should be used for shipping and storage containers where the color of the product is important or when metallic impurities must be minimized. Formamide attacks natural mbber but not neoprene. As a result of the solvent action of formamide, most protective paints and finishes are unsatisfactory when in contact with formamide. Therefore, formamide is best shipped in containers made of stainless steel or in dmms made of, or coated with, polyethylene. Formamide supphed by BASF is packed in Lupolen dmms (230 kg) or Lupolen canisters (60 kg) both in continental Europe and overseas. [Pg.509]

Heat stabilizers protect polymers from the chemical degrading effects of heat or uv irradiation. These additives include a wide variety of chemical substances, ranging from purely organic chemicals to metallic soaps to complex organometaUic compounds. By far the most common polymer requiring the use of heat stabilizers is poly(vinyl chloride) (PVC). However, copolymers of PVC, chlorinated poly(vinyl chloride) (CPVC), poly(vinyhdene chloride) (PVDC), and chlorinated polyethylene (CPE), also benefit from this technology. Without the use of heat stabilizers, PVC could not be the widely used polymer that it is, with worldwide production of nearly 16 million metric tons in 1991 alone (see Vinyl polymers). [Pg.544]

Building Wires. These wires conduct electricity at relatively low voltages (eg, 110 V and 220 V). Typically they contain a metallic conductor (copper or aluminum) that is insulated with polymeric compounds based on polyethylene or PVC which are appHed over a conductor using an extmder. [Pg.323]

AppHcation of an adhesion-promoting paint before metal spraying improves the coating. Color-coded paints, which indicate compatibiHty with specific plastics, can be appHed at 20 times the rate of grit blasting, typically at 0.025-mm dry film thickness. The main test and control method is cross-hatch adhesion. Among the most common plastics coated with such paints are polycarbonate, poly(phenylene ether), polystyrene, ABS, poly(vinyl chloride), polyethylene, polyester, and polyetherimide. [Pg.134]

High density polyethylene (HDPE) is defined by ASTM D1248-84 as a product of ethylene polymerisation with a density of 0.940 g/cm or higher. This range includes both homopolymers of ethylene and its copolymers with small amounts of a-olefins. The first commercial processes for HDPE manufacture were developed in the early 1950s and utilised a variety of transition-metal polymerisation catalysts based on molybdenum (1), chromium (2,3), and titanium (4). Commercial production of HDPE was started in 1956 in the United States by Phillips Petroleum Company and in Europe by Hoechst (5). HDPE is one of the largest volume commodity plastics produced in the world, with a worldwide capacity in 1994 of over 14 x 10 t/yr and a 32% share of the total polyethylene production. [Pg.379]


See other pages where Polyethylene metals is mentioned: [Pg.245]    [Pg.294]    [Pg.23]    [Pg.22]    [Pg.379]    [Pg.245]    [Pg.294]    [Pg.23]    [Pg.22]    [Pg.379]    [Pg.165]    [Pg.271]    [Pg.194]    [Pg.229]    [Pg.230]    [Pg.88]    [Pg.377]    [Pg.165]    [Pg.168]    [Pg.178]    [Pg.451]    [Pg.454]    [Pg.514]    [Pg.172]    [Pg.398]    [Pg.460]    [Pg.74]    [Pg.478]    [Pg.478]    [Pg.324]    [Pg.372]    [Pg.397]    [Pg.406]    [Pg.495]    [Pg.274]    [Pg.45]    [Pg.148]    [Pg.23]    [Pg.372]    [Pg.191]    [Pg.194]   
See also in sourсe #XX -- [ Pg.124 ]




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