Automotive elastomeric seals

Riga [8] used TG and TMA for quality control of automotive elastomeric seals. TMA was used to confirm the Tg of the polymer, as well as the thermal expansion coefBcient. TG was also used to provide data on the composition of the compounded seal material. Both of these techniques provide critical information for control of quality but it was pointed out that these techniques alone coidd not predict failure of the seals unless a very specific problem was pointed out. 

Typical TG-DTA applications are thermal and oxidative stability, determination of relative components, decomposition temperatures and thermal decay reactions, action of heat stabilisers, thermal ageing. TG-DTA has been used to screen candidate automotive engineering plastics, elastomeric seals and lubricant additives to establish quality and understand field failures [300], The organometallic chemicals used as lubricant additives were employed to increase the thermal and/or oxidative stability of passenger car and heavy-duty diesel oils. 

Park, Junhong, Thomas Siegmund and Luc G. Mongeau (Purdue University), Society of Automotive Engineers, P erNo. 2001-01-1411, Sound Transmission Through Elastomeric Sealing Systems . 

With the high-temperature solution polymerization processes, various ethylene homo- and copolymers with different average molecular mass and copolymer compositions are produced. The product portfolio comprises PE-HD, PE-LLD, PE-VLD, and the ethylene/propylene elastomers (EPM, EPDM) (see Figure 2). The thermoplastic products have a wide range of applications [1]. The elastomeric ethylene/propylene copolymers can also be applied widely in the automotive industry, for plastics modification, in industrial applications such as seals, in electrical cables, and in tires [2], Uncured ethylene/propylene copolymers are applicable as viscosity index improvers for lubricant oils [5]. 

Commercial elastomeric blends of ethylene terpolymer/PVC system (Alcryn ) are used in outdoor weather stripping, seals and gaskets, coated fabrics, pond linings and a variety of other extruded and molded goods for automotive and industrial applications. 

POEs have been used in both plastic rmd rubber applications. These elastomeric polyethylenes have ability to be cross-linked via peroxide, irradiation, and moisture (if silane grafted). Potential applications include tubing, impact modifiers, low-voltage cable insulation, elastic films, foams, shoe soles, belts, automotive hoses, medical applications, gasket seals, and other electrical applications. 

Large quantities of elastomeric materials are used to produce a m)uiad of products such as hoses, cable insulation, O-rings, seals and gaskets, belting, vibration mounts, flexible couplings, expansion joints, automotive and airplane parts, electrical parts and accessories. With such a wide variety of applications requiring very diverse properties, it is essential that an... 

These elastomeric compounds are foimd in a variety of applications, including reinforced hose, seals, gaskets and profile extrusions, flexible and supported tubing, automotive trim, functional parts and imder-the-hood components, mechanical goods, and wire and cable jacketing. 

Polyurethanes are the most versatile polymer systems used to formulate elastomeric sealants. Polyurethane sealants are sold both as two-component and one-component gun-grade compositions, packed in cartridge or in bulk. Applications are similar to those of the polysulfides, including the insulated glass markets and sealing automotive windshields. 

Neoprene sealants are available as one or two part systems with good elastomeric properties, modulus, exterior durability and abrasion resistance, but poor color stability and extended cure times when compounded for gunning. Many of their applications, such as chemical plant use, automotive, marine, and concrete pipe seals are due to their excellent oil and chemical resistance. 

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