Bumper to Bumper

While a concept car from one particular supplier or OEM is limited in scope, Canadian Plastics’ 2003 concept car will demonstrate a range of resin and molding innovations from many suppliers. To be accurate, let’s not call it a concept car, because most of these technologies are in commercial production. Let’s call it a compilation car, because it shows the combined efforts of many automotive design teams.

So, use your imagination and let’s start the tour.

THE FRONT END

The front-end module found on the 2003 Porsche Cayenne and Volkswagen Touareg uses StaMax P long-glass fibre polypropylene thermoplastic developed by an Owens Corning joint venture. The composite module is lighter, stronger and can be more cost effective than its steel counterpart.

“OEMs have been reluctant to specify a long glass-fibre thermoplastic composite for the structures of heavy vehicles like SUVs. These two automobiles go a long way to prove to the industry that StaMax P offers structural performance in addition to obvious benefits such as weight reduction, cost savings and parts integration,” says Andrew Hopkins, general manager of OC Automotive.

THE NOSECONE

The industry’s first injection-molded thermoplastic windshield wiper bracket system, otherwise known as a nosecone, appeared on the 2003 Lincoln Town Car. A team from Ford Motor Co., Carlisle Engineered Products, Valeo and DuPont Engineering Polymers collaborated on the design.

“This is the first step in a major shift for the industry related to wiper systems,” says Gary Skrypec, Carlisle senior product engineer.

The thermoplastic unit, made of DuPont Rynite post-consumer recycled PET polyester resin, eliminates some post-finishing operations and reduces weight by 10% compared with a previous component of SMC (sheet molding compound).

“Rynite PET provides the stiffness, flatness and structural capabilities needed for large, load-bearing parts, including forces from wiper motor torque,” explains Chris McBride of DuPont Engineering Polymers.

THE ROOF

A roof module for the MCC Smart car is the first large vehicle body part in which glass and plastic with similar stylistic characteristics have been combined to produce a high-quality painted appearance.

The roof module incorporates a “paintless film molding” (PFM) film from BASF. This material is a coextrusion of BASF’s Luran S (ASA and ASA/PC) capped with two layers of PMMA. First the PFM is thermoformed to the shape of the roof. A layer of glass-fibre reinforced polyurethane foam is then injected onto its inside surface.

BASF believes the roof module demonstrates the huge potential of PFM-System as a cheaper alternative to painting large automotive body parts. It is said to be ideal for modularized designs since it enables a perfect color match and uniform surface finish, even if the parts are from different suppliers.

THE DOORS

Using Celstran long fibre-reinforced thermoplastic (LFRT) from Ticona for carrier plates in the doors puts Jaguar at the leading edge of automotive design. Metal carrier plates were replaced with a Celstran polypropylene matrix reinforced with 30% long glass fibres. The carrier plates measure 1.0 by 0.7 m and weigh about 1.7 kg. Functional elements such as internal door openers and speakers are directly built into the door module.

The Celstran material for this application has good thermal resistance, high dimensional stability, good insulation characteristics and high tensile strength.

THE MIRRORS

Magna Auteca of Austria has chosen BASF’s Ultraform POM for various components in its new power actuator for electric mirrors. This material combines high stiffness, strength, good frictional properties, resilience and dimensional stability.

Magna has found the material can be processed quickly and is easy to demold. The molded parts exhibit low post-molding shrinkage.

THE WINDOWS

Small plastic windows are already standard components on vehicles but, so far, economically feasible production of large plastic windows has remained elusive. Exatec, in cooperation with Battenfeld and Summerer Technologies, has now developed a cost-effective solution for manufacturing large polycarbonate windows.

With the innovative IMPmore in-mold pressing process, it is possible to manufacture large automotive windows from polycarbonate with low tension. The windows are made highly scratch resistant by a special surface coating.

Polycarbonate windows offer a weight reduction of approximately 40% to 50% compared with glass.

A production cell on display at NPE consisted of a two-platen Battenfeld HM injection molding machine, a mold optimized for the IMPmore process, and an ABB robot.

A core element of the IMPmore process is a compression-injection molding process implemented by a special mold technology. With this technology, large thinwall parts can be injection molded with long flow distances, low clamping force and low tension.

Looking ahead, Battenfeld says such a production cell would also be able to mold on seals, or integrate lamps and fastening elements. Another potential benefit is an increased scope for 3D design.

THE BODY PANELS

Vertical and horizontal body panels, truck boxes and structural composites are the target for a new resin developed by Cyclics Corp. and Dow Automotive. The two companies have just announced a long-term agreement for marketing the cyclic form of polybutylene terephthalate (CBT) resins into the global automotive, bus, truck and rail markets.

“CBT resins will lead to significant performance improvements over traditional solutions, as well as weight reduction, minimized scrap rates, and lower tooling costs,” says Jane Palmieri, new business development manager for Dow Automotive.

CBT resins polymerize reactively like thermosets, but have the material properties of thermoplastics. They are solid (pellet, powder, flake) at room temperature but become a very low viscosity material when heated above 300 F. When mixed with specific tin or titanium polymerization catalysts the PBT rings in cyclical form open and connect to form high molecular weight PBT thermoplastic.

Cyclics has demonstrated the use of CBT resins in compression molding, injection molding, slurry processing, compounding, extrusion, reactive injection molding (RIM, SRIM), resin transfer molding, pultrusion and rotational molding.