Jyco sees bright future for TPV

Hood-to-cowl seals (center) and glass run channels are among the applications Jyco is pursuing for its TPV material.

Tier 1 supplier Jyco Sealing Technologies is on the leading edge of what it describes as a "major transition" under way in automotive sealing technology.

Through the 1990s, it says, EPDM (ethylene propylene diene monomer) was the material of choice for automotive closure sealing systems. But that material's reign is being rapidly dethroned by TPV (thermoplastic vulcanizates). This compound of EPDM and polypropylene performs like EPDM, yet processes with the ease of plastic.

Advantages include performance enhancements, cost and weight reductions, and accelerated cycle times. Unlike EPDM, it can be pigmented for color coordination with doors and body panels. It offers safety and environmental advantages as well, as it can be processed with non-hazardous and non-flammable blowing agents. Scrap is 100% recyclable, accounting for the cost reduction.

The innovation with Jyco's TPV material is as much in the process as it is in the material, according to Sam Jyawook, company President and CEO.

With a high polymer content, "TPV is not the easiest thing to process," said Sam Jyawook, President and CEO of Jyco. The company is using a process from Trexel called MuCell, which involves injection into the mold of a supercritical fluid to create foaming.

"The foaming is critical," he said. "Most people haven't been able to produce good foam products. Most of it has an open-cell structure, but with this injection process we've been able to achieve a closed-cell structure that doesn't require a surface finish."

The MuCell process has been used for other products, but not for weather-stripping, which is one of the applications Jyco is pursuing.

OEMs seem to be committed to TPV, in Jyco's view. At last year's Performance Elastomers Conference in Cleveland, General Motors estimated that its use of TPV in vehicle closure sealing will double to 20-30 part numbers by 2004, and to 60 part numbers by 2010. German and Japanese automakers are further ahead; the latter are already using TPV in 23% of their glass-run-channel applications, according to Jyco.

Another application for Jyco's TPV material is windshield wiper fluid overflow tubes.

Still, the transition to TPV from EPDM in North America is apparently not happening as rapidly as the OEMs would like. The speed bump for most of their suppliers is the capital investment needed to adapt existing processes. Some have as many as 30 EPDM extruding lines, with an investment of approximately $2.5-3 million in each.

Jyco Sealing Technologies is unique among the North American sealing suppliers, in this respect; the company is dedicated exclusively to TPV. Although operations have been running less than one year, Jyco already has contracts or pending proposals with four OEMs.

As Vice President of Engineering at Kingston-Warren in the 1980s, Jyawook was a major proponent of EPDM, leading the sealing industry's transition away from SBR (styrene butadine rubber). He also pioneered the application of finite-element analysis and modeling to automotive sealing systems, and was responsible for manufacturing innovations such as multi-durometer extruding and robotic assembly. Later, as President of Thona Corp., he helped the company achieve 900% growth during the 1990s, introducing a number of innovations in extruding and glass encapsulation process technology.

- Patrick Ponticel

Delphi plastic provides fire protection

Delphi's intumescent thermoplastic can be molded to fit snugly on firewalls and other spots where fire resistance is needed.

Delphi Research has developed a flame-resistant material that can be used to augment metal firewalls or provide compact, lightweight protection for gas tanks. The company is hoping to license or sell the technology, which is currently shipping in evaluation quantities.

The material, internally called FirmGuard, is a thermoplastic that is intumescent, which means it expands or foams when heated. Based on a high-density polyethylene, it reacts to heat at 300°C (570°F), foaming yet remaining in place as it expands. That eliminates danger from dripping, so it doesn't leave gaps in the protective shield.

When the Delphi thermoplastic is exposed to fire, it expands. Though it foams up, it does not move, so no gaps form.

"No holes or leaks developed in tests with intense fires lasting 20 minutes," reported Ismat Abu-Isa, a research fellow at Delphi Research Labs in Shelby Township, MI. Those trials included horizontal and vertical fire shield tests, which have temperatures up to 800°C (1470°F).

That ability to maintain a breach-proof barrier means that shielding can be relatively thin. "I think for most applications, 1 mm is sufficient," Abu-Isa added.

Another benefit is that the material can be formed to match the exact shape of the firewall or gas tank. Designers don't have to leave space between the metal and the material, saving space while reducing weight compared to metal shielding. Tests show a high level of resistance to automotive fluids such as diesel fuel, engine coolant, and transmission fluid. The material also boasts good sound-damping characteristics.

Pores in the foam help absorb heat but do not create openings that could let fire pass through the barrier.

FirmGuard can be produced using many techniques, including blow molding and extrusion. In addition to polyethylene base materials developed originally, the intumescent product can be used with nylons, polypropylenes, and polystyrenes. Recycled material can be added to new materials without dramatically reducing fire resistance. Delphi licensing executive Richard Marczewski said that Delphi is currently trying to license the material to a large user or resin compounders. Delphi does not have the facilities to produce resins, so it has no intention to sell the material itself. Marczewski noted that the material is "relatively inexpensive," but did not elaborate since the impact of material costs will vary widely depending on the product they're used in.

Though automotive is a key application area, the material is also being tested for use in shipping pallets. There, its light weight and fire resistance will give it an edge over wood. Pallet designs are closer to commercialization, since there are fewer critical design and reliability issues, Abu-Isa noted.

- Terry Costlow

Plastic makers researching role in 42-V systems

While automakers and electronics companies look at the system and component implications of the pending changeover to 42-V power systems, engineers in the plastics industry are also doing plenty of research into the materials that will be needed to make sure the electronic systems operate safely.

The plastic bodies of connectors and the insulation for wires may have to be changed to meet heat and arcing concerns that come with the higher voltage. Many material makers have already done extensive research to find the most cost-effective plastics. Working with 42 V is not a huge challenge for companies that provide plastics used in aircraft or power plants, but getting the right pricing, weight, and ruggedness is a key issue for the high-volume automotive market.

At the Oct. 1 Engineering Thermoplastics Conference in Chicago, BASF, GE, DuPont, and others discussed research projects. Some executives feel 42-V systems represent one of the biggest emerging markets for thermoplastics.

"Nanocomposites, 42-V automotive systems, and fuel cells are the key industry trends," said Dustin Majumdar, Global Product Manager at GE Plastics in Selkirk, NY. "42 V has huge implications: higher speeds, arc resistance, and higher heat."

Though often overlooked, plastics will play a critical role in the planned changeover to higher voltage systems, it was agreed.

"Plastics are extremely important," said Al Kurkowski, Automotive Project Manager at BRG Townsend Inc., a Mt. Olive, NJ, research firm that recently completed a study on 42-V systems. "Connectors are one of the most critical, since if you have an accidental disconnection at 42 V, you get a catastrophic failure that may cause disintegration of the connector."

That danger comes because of the higher temperatures that will occur, as well as because of the increased chance of arcing when active circuits are broken.

"You will have 12 times the induction with 42 V. If you have 12 times the induction and one-third the current, you will have higher probability for arcing," said Randy Sferrazza, NAFTA Product Development Manager at BASF Corp. in Wyandotte, MI. He explained that arcs are self-extinguishing with 12-V systems, but at 42 V, there is a possibility of continuous arcing, which could cause fires. "Where arcing is possible, we will need higher qualified plastics," he said.

In some regards, the key job will be to adopt plastics that are used in applications with power levels closer to those of the future generation of high-voltage automobile systems. "We've got materials in electronics at levels above automotive electronics. It's just a matter of seeing which materials slip over into the automotive arena," Sferrazza said. A variety of flame-retardant materials are being examined by plastics suppliers who want to provide the optimum balance between price and performance, with connectors currently getting most of their research dollars. However, observers noted that connectors are not the only area where plastics might be changed.

"Even the wires will change; they'll be thinner. We might need different insulation materials," said Brian Fish, Development Specialist at DuPont Engineering Polymers Automotive in Troy, MI. He noted that DuPont has a development team that is supported by other business units, and that DuPont is the only materials supplier in the MIT/Industry Consortium on Advanced Automotive Electrical/Electronic Components and Systems that is driving the development of 42-V techniques.

While manufacturers are watching automakers and doing research, they aren't rushing to roll out specific products. Though automakers are unveiling a few limited-production vehicles, no one expects to see any big changeover for five to 10 years. "It would be premature to have any resins now," Majumdar said.

Carmakers are beginning to roll out vehicles, but it's expected to be a few years before there is much activity in high-volume vehicles. Toyota has unveiled a 42-V car in Japan, and GM plans to unveil a hybrid pickup in 2004. GM Vice President of R&D Larry Burns recently said that although there are technical hurdles and a chicken-or-egg issue with automakers and suppliers each waiting for the other to make product announcements, "GM absolutely sees the 42-V system as an enabler for future vehicles."

- Terry Costlow