Opinions differ, but the relationship between the automobile and chemical industries probably began with the invention of the rigid thermosetting plastic bakelite in 1907 and its use by Rolls Royce for the knob on a gear lever.
Today, advanced plastics are the norm in automobiles — and their influence only continues to grow.
Henkel, Düsseldorf, Germany, for example, has taken aim at engine covers, transmission covers and electronic components integrated with a growing number of plastic parts that need sealed to the core component unit.
At the moment, the most commonly used plastic-to-metal substrate sealing method is the press-in-place (PIP) process. This involves manually applying a solid rubber gasket or O-ring onto the parts; it risks displacement during compression.
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The company’s new Loctite AA 5884 polyacrylate gasketing technology makes possible the direct dispensation of a liquid gasket onto the customers’ part.
These static gasket materials positioned between two flanges held together by fasteners close the gaps between these surfaces to prevent leakage of fluids or gases. Automated, high-precision equipment applies a bead of liquid elastomer to form the gaskets. To keep the sealing functional and leak-free for a prolonged period, the gasket must resist the medium being sealed. At the same time, it must withstand the application’s temperature, pressure and the joint’s micro-movement.
Ultraviolet light within seconds cures the liquid gasket, which becomes a solid compression gasket with no knit line. This reduces the risk of rework and leakages. It also lowers the overall cost by automating the gasketing process and eliminating the inventory and complexity of the PIP solid gaskets.
Figure 1. Henkel’s new polyacrylate gasketing technology allows direct dispensation of a liquid gasket onto automobile parts. Source: Henkel.
Meanwhile, high-performance automotive component supplier Husco, Waukesha, Wisc., in collaboration with SABIC, Sittard, the Netherlands, plans to develop innovations for next-generation vehicles based on ULTEM resin polyetherimide (PEI).
Husco has over a decade of experience with ULTEM resin. It uses the PEI in components for the electro-hydraulic control valves that govern variable valve timing, variable displacement oil pump control, and cylinder deactivation control — all of which enhance fuel efficiency and vehicle performance.
“We require extreme precision and micron-level dimensional stability across a broad temperature range that starts at -40°C and goes up to well over +150°C in applications like engine valve components, which need to survive sometimes as many as 700 million cycles over their lifetimes and constant vibration loads,” says Matt Schmitz, Husco’s engineering programs director.
“ULTEM resin is the best thermoplastic we have found that meets those needs. The other major benefit it offers is being amorphous, which reduces impacts from process settings that may be seen with other high temperature rated semi-crystalline materials,” he adds.
The two companies now are developing new technologies for drive trains and braking systems.
Meanwhile, polyurethane ester and polyurethane ether foam specialist FoamPartner, Wolfhausen, Switzerland, is focusing on both vehicle comfort and acoustics.
Figure 2. Tailor made, lightweight thermal and acoustic foams aimed at next generation electric vehicles. Source: FoamPartner.
“One of the key advantages of electric vehicles is the ability for fast acceleration and low-noise drives. But the latter places higher demands on the insulation of the passenger compartment against rolling and wind noises,” says Kay Kosar, head of marketing and sales, acoustics & thermal solutions, Europe at FoamPartner. “At the same time, the power consumed by heating and air conditioning must be minimized to ensure maximum driving ranges. In both disciplines, our advanced foam solutions are in their element,” he adds.
Together with mobility think tank and long-time partner Rinspeed, Zumikon, Switzerland, the company has developed a concept car to illustrate how effective its tailor-made acoustic and thermal insulation foams can be in new generation vehicles.
To meet the automotive sector’s rising demand for its foams, FoamPartner is “significantly” expanding production capacity at its Duderstadt site in Germany.
Meanwhile, Clariant, Charlotte, N.C., has tackled time and cost issues associated with batch-to-batch reformulations of automobile color coatings.
Its Hostatint SI range of pigment dispersions show what the company describes as “unparalleled compatibility” with the diversity of industrial coatings bases, plus a tinting consistency capable of repeatable color matching to U.S. automobile industry standard shades.
Clariant describes the new pigment dispersions as the first “drop-in ready” answer to problems frequently caused by a dispersion’s incompatibility with various industrial coatings bases — notably, inconsistent tinting and finished product color float, or post application color rub-up.
Seán Ottewell is Chemical Processing's editor at large. You can email him at [email protected].
