Gasket acrylic

Polyacrylate elastomers find limited use in hydrauhc systems and gasket apphcations because of their superior heat resistance compared to the nitrile mbbers (219,220). Ethylene—acrylate copolymers were introduced in 1975. The apphcations include transmission seals, vibration dampers, dust boots, and steering and suspension seals. Further details and performance comparisons with other elastomers are given in reference 221 (see also Elastomers, SYNTHETIC-ACRYLIC ELASTOTffiRS). 

Ethylene copolymers with methyl methacrylate and ethyl, butyl, and methyl acrylates are similar to EVA products but have improved thermal stability during extrusion and increased low-temperature flexibility. The commercial products generally contain 15-30% of the acrylate or methacrylate comonomer. Applications include medical packaging, disposable gloves, hose, tubing, gaskets, cable insulation, and squeeze toys. 

Enichem and DuPont are two suppliers of acrylic elastomers. It is estimated there are 9000 t/yr of these elastomers used in the United States. The principal uses of acrylic elastomers are in automotive applications requiring both oil and heat resistance. These include transmission, valve stem, crankshaft, pinion, and oilpan gaskets and seals. In addition hose, tubing, rolls, and belts are made from acrylic polymers. 

These are made in emulsion or suspension systems involving the copolymerization of ethyl acrylate with the acrylate esters of higher-molecular-weight alcohols. These materials have excellent sulvenl-resi.stunl properties and stability at elevated temperatures. A major use is fur automatic-transmission gaskets lor automobiles. 

Regrettably, a refinery worker was injured by sulfuric acid because a 4-inch (10 cm) piping substitute gasket failed. The acrylic fibers in the nonasbestos gasket material were attacked by the acid. The asbestos fibers had resisted the chemical attack. 

Multi-well modified Boyden chambers can be obtained from Neuro Probe Inc. (Gaithersburg, MD). Model AP48 has been widely used for endothelial cell chemotaxis assays. The apparatus consists of top and bottom acrylic plates, a silicon gasket and assembly screws. The bottom plate has 48 wells, each with 25 pL final volume. These correspond to holes on the top plate, and form the upper wells when the chamber is assembled. The filter (polycarbonate, 25 x 80 mm) is placed between the top and bottom plates, and a gasket is placed over the filter to create the seal. The apparatus can be purchased with a selection of accessories, such as curved forceps, filter clamps, and wipers. These are required to process the filters after use. Filters can also be obtained from Nucleopore Inc. (Pleasanton, CA) and Costar (Cambridge, MA). 

Nipol AR. [Zeon] Acrylic rubber used for seals, o-rings, gaskets, automotive parts, etc. 

Room temperature cured (RTV) silicones are used as potting compounds and as in situ formed gaskets. These compositions are toughened by the addition of styrene or butyl acrylate which form minute strands of fiber in situ when they polymerize.21 Silicone sealants and coatings are being used in the NASA space shuttles.22 Paintable, fast curing-octoate-cured silicone sealants are also available. Simple tests for utility, based on a filled glass tube, have been described.22... 

Acrylic window pane fiber-reinforced lorylic sun shield Vinyl gaskets... 

This company s new 2600-093 Micro-Kiss series mix-dispense valves are designed for the low-flow mixing and dispensing of two-component adhesives and sealants such as silicones, epoxies, urethanes, and acrylics. The valves can be used to apply two-part adhesives and sealants for bonding, gasketing, potting and filling processes in aerospace, appliance, contractor, defense, electronics, filters, marine. 

Uses Phenolic, adhesion promoter, chem. resist, aid for drum and pail coatings, latex and phenoxy polymers crosslinking agent for water-based polymers intended for low VQC applies. food pkg. adhesives, coatings, paper, closures with sealing gaskets for food containers Features Thermosetting compat. with various waterborne acrylic, epoxy, and phenoxy resins... 

Uses Heat stabilizer for PVC, ABS, polyolefins, elastomers, acrylics, adhesives, nylon, PC, PU, PS, coalings, PET food pkg. adhesives, coatings, nibber articles, polymers, closures with sealing gaskets for food containers... 

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