Automotive components body panels

ABS/PC blends are used in a variety of automotive components such as instrument panels, flaps for glove compartments, dashboards, cladding for steering wheel columns, ventilation ports, spoilers, wheel covers, and protective side trims. Flame-retardant ABS/PC blends are used in office equipment and business machine housings. Chlorine or bromine-free flame-retardant ABS/PC compositions contain organophosphate/PTFE powder dispersions (Freitag et al. 1991). ABS/PC blends have been used in automotive exterior body panels first in the GM s former Saturn... 

Considerable amounts of EPM and EPDM are also used in blends with thermoplastics, eg, as impact modifier in quantities up to ca 25% wt/wt for polyamides, polystyrenes, and particularly polypropylene. The latter products are used in many exterior automotive appHcations such as bumpers and body panels. In blends with polypropylene, wherein the EPDM component may be increased to become the larger portion, a thermoplastic elastomer is obtained, provided the EPDM phase is vulcanked during the mixing with polypropylene (dynamic vulcani2ation) to suppress the flow of the EPDM phase and give the end product sufficient set. 

Sheet molding compounds (SMCs) and bulk molding compounds (BMCs) are the dominant materials used in automotive applications. These composites of unsaturated polyester resin, fillers and fiberglass have advantages of high stiffness, heat resistance and low coefficient of expansion. Coupled with low creep resistance, which is a distinct advantage over thermoplastic competition, and low-profile additives, which can yield Class A surfaces, these materials are well suited for applications from exterior body panels to under the hood components. 

Xycon Hybrid Resin. [Amoco] Two-component polymer thermoset for truck-body panels, after-market automotive parts, recreational vehicles, outdoor equip., tubs and showers, elec, parts. 

PA/ABS high temperature warp resistance, chemical resistance, good processability, and superior appearance, automotive (body panels, under-the-hood connectors and components, fuel tanks, bearings, bushings, cams). 

Alloys made by combining polyarylamide with PA and polypropylene (which could be hghtly glass reinforced) offer low water absorption, even at high PP levels, good impact resistance, and lower density, which reduces price per volume. Targeted applications include automotive body panels, and electrical components. 

There has been a trend in recent years to move towards the electrostatic deposition of paints for exterior automotive applications. Reasons for this include improved paint transfer efficiency. Normally, plastic parts need to be painted with a conductive primer prior to the electrostatic painting of base and clear coats. One of the most recent developments in the area of external automotive applications is that of intrinsically conductive resins for electrostatic painting. Currently there are commercial applications for body panels that utilize PPE/PA that contains carbon black as the conductive component. In the USA, a mirror shell application uses PPE/PA where the conductivity is achieved through the incorporation of graphite nano-tubes. 

Such glass fiber-reinforced composites based on the unsaturated polyester thermosets are usually fabricated as sheet molding compounds (SMC) and bulk molding compounds (BMC). These are widely used in various metal replacement applications because of their cost-effectiveness, rigidity, light weight, and corrosion resistance properties particularly useful in transportation (cars and trucks), constmction, pipe, and tank applications. Automotive and tmck body panel and strucmral component applications of SMC include doors, hatchbacks, hoods, front grilles, etc. Some nonautomotive applications of SMC and BMC include sanitaryware (bathtubs, shower stalls, sinks), appliances, business machine, and electrical components. 

Dow Chemical claims a patent on a blend [11] with a decreased tendency toward delamination, which exhibits a desirable balance of properties, a high level of impact resistance, solvent resistance, and processability. The product can be blown into films, spun into fibers, extruded into sheets, formed into multilayer laminates, and molded into any desired shape and can be used in data storage apparatus, appliance and instrument housings, motor vehicle body panels, and other parts and components for use in electrical, automotive, and electronic industries. 

The use of fiber reinforced unsaturated polyester resin composites in the form of sheet molding compound (SMC), bulk molding compound (BMC) and preform molding exceeded 475 000 tons (approximately one billion pounds) in North America and Europe in 1995. Many applications were in the transportation industry such as automotive body panels, truck components and semi-structural parts (Table 1). Other applications are in sanitary ware (bathtubs, showers, sinks), applicances, business machines and electrical components. 

Interior components make up the largest use of plastics in automotive vehicles, in applications such as instrument panels (IPs), body panels, door panels, dashmats, seat backs, seat bases, steering wheels, and airbag covers. 

Automotive applications - automobile bumpers, grilles, wheel covers and body panels, electrical and electronic components (Figure 5.12). 

Typical vinyl ester automotive applications are body panels, firewalls, fuel cell plates, lighting components for headlamps, pickup truck cargo boxes, radiator supports, running boards for SUVs, trailer truck cab/roofs and wind deflectors, rocker covers, wheel covers, and windshield surrounds. 

Dow Automotive entered an alliance with Cyclics to develop cyclic butylene terephthalate (CBT) resins for automotive applications. Research will focus on a number of automotive structural composites, including vertical and horizontal body panels and truck boxes. The companies expect that components will be able to be formed using a number of techniques, including compression and injection moulding. CBT resins will contribute to lighter weight vehicle design and be recyclable. 

Corrosion is defined as the destructive and unintentional attack on a metal it is electrochemical and ordinarily begins at the surface. The problem of metallic corrosion is significant in economic terms, it has been estimated that approximately 5% of an industrialized nation s income is spent on corrosion prevention and the maintenance or replacement of products lost or contaminated as a result of corrosion reactions. The consequences of corrosion are all too common. Familiar examples include the rusting of automotive body panels and radiator and exhaust components. 

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