Automotive components fascias

MAJOR PRODUCT APPLICATIONS electrical connectors, automotive components, automotive fascia, automotive seals, gaskets and bearings, aerospace components, friction products, putty compounds, adhesives... 

One of the most important applications for impact-modified PP is automotive TPO, commonly used for automotive bumper fascia, external body cladding, and interior trim. Compounds are typically three-component blends of ICP with talc and an impact modifier such as a metallocene plastomer or EPR. The impact modifier provides low temperature toughness but softens the matrix. The talc particles restore the stiffness of the compound but detract from impact strength. The objective of TPO compounding is to select the combination of the three components that provides an optimum balance of stiffness and impact strength. 

PPO Automotive grill fascia panels Switches, electrical fittings Ducts, light fitting housings, washing machine parts, dishwasher components... 

The main applieations for PBT in the car interior include parts of the instrument panel sueh as ashtrays and other interior trim. For exterior applieations PC/PBT blends are used mainly in the manufaeture of automotive bumper fascia. Other uses for PBT include windscreen wiper arms, mudguards, mirror housings and door handles. PBT is used in applications where a high quality, weather resistant surface is a key requirement for components. 

Paintable interior automotive components include hard trim parts, instrument panel skins, door panels, and airbag covers. Exterior components include bumper fascias, body side cladding, rocker panels, and vent grilles. The preferred substrate for these components has been thermoplastic polyolefins (TPOs), a material with low flexural modulus and low surface energy. It is considerably difficult to promote paint adhesion to TPOs without the use of predominantly oxidative surface treatment techniques, such as flame or atmospheric plasmas, or a chemical adhesion promoter, to prepare the surface to accept and wet-out paint. 

Some degree of flexibility must be built into these primers because after topcoating with conventional basecoat and clearcoat, the flexible clearcoat systems have to pass the low-temperature impact resistance required for automotive bumper fascias and other components in the impact area of the vehicle. 

At the present time most fascia are about 0.125" - 0.150" thick and are manufactured employing a RIM elastomer with a nominal room temperature flexural modulus of 172 MPa. But, the trend in the automotive industry is to go to thinner fascia produced with the RIM elastomers with 345 MPa nominal flexural modulus. In Table III are shown the average usage of the major components of both the 172 MPa and 345 MPa RIM systems. These average values are the best estimate based on known formulations currently being used in production. 

A recent commercial blend of ABS contains thermoplastic polyurethane elastomer as the main blend component. The blend was introduced in 1990 by Dow Chemical Co., under the trade name Prevail . These blends characteristically exhibit low modulus (340 to 1000 MPa) and high impact strength at low temperamres, e.g. notched Izod values of 370 to 1500 J/m at -29°C. The TPU component of the blend imparts high toughness and also allows paintabihty without a primer. ABS component imparts heat resistance (for paint ovens) and good tensile strength in the blend. The blend is projected to find applications in the automotive markets, particularly as paintable, soft bumper fascias. Typical properties of commercial ABS/TPU blends are shown in Table 15.6. 

The automotive industry started to use plastics in 1946. Since then, its content steadily increases (see Figure 16.4). Today, the plastics for automotive apphcations are dominated by polymer alloys, blends, and composites. The reason for it is the need for automotive parts to show a wide range of performance characteristics that are virtually impossible to meet using a single-component polymer. Thus, for example, in Saturn, front fenders and rear quarter panels are from PA/PPE, door outer skins are from PC/ABS, the bumper fascias are TPO, etc. 

While the polyketone terpolymer derived from carbon monoxide, ethylene, and propylene is economical with some attractive properties, such as heat, chemical, permeation, and abrasion resistance, it suffers from low-impact strength. One cost-effective approach to overcoming this shortcoming and upgrading its performance profile for automotive applications such as wheel covers, wheel caps, fuel filter necks, fuel tanks, fuel tubes, center fascias, door handles, roof rack covers, gears, junction boxes, connectors, and seat backs, as well as electric/electronic components and durable household items involves blending with polyamides including a rubber modification (Lee et al. 2013). 

Typical products are automotive exterior trim, fascia components, spoilers, window track tapes, boots, bellows, underhood wire covering, connectors, hose, and belts appliance seals, power tool components, ski boots, and camping equipment. ... 

Automotive is the largest market for PBT. Electronic components and housings are the main applications area for PBT in the automotive sector. Exterior applications are the next most important market with main uses being bumper fascias, mudguards, door handles, mirror housings and wiper arms. Interior applications include parts of the instrument panels such as ashtrays and... 

Bulky, complex shapes and thin-walled articles can be produced in this way. Reaction times of a few seconds are possible, and mold residence times of one or two minutes have been achieved. RIM consumes less energy and uses less expensive equipment than conventional injection-molding processes. The process is used to make fascias, bumpers, and other flexible automotive parts. Fillers may be incorporated in the components to lower cost and increase rigidity. This fabrication technique is discussed further in the section on Fabrication of Plastics under Injection Molding. ... 

In quite a variety of applications, thermoplastic elastomers have replaced conventional thermoset elastomers. Typical uses for TPEs include automotive exterior trim (bumpers, fascia, etc.), automotive underhood components (electrical insulation and connectors, and gaskets), shoe soles and heels, sporting goods (e.g., bladders for footballs and soccer balls), medical barrier films and protective coatings, and components in sealants, caulking, and adhesives. 

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