Elastomer R&D on full charge

London - Rubber materials suppliers, processors and product developers are continuing to advance innovative technologies to meet the dynamic and fast-changing requirements of automotive vehicle manufacturers worldwide.

Regionally the focus of these efforts is Asia-Pacific, which is a major hub for vehicle manufacturing and accounts for a sizable market share of sales across all vehicle segments.

The region’s automotive industry will, therefore, be at the centre of innovation over the coming years, driven by rising adoption of electric vehicles (EVs) and connected vehicles, as well as growth in the luxury car segment. 

According to industry observers, the Asian automotive industry is entering a period of sustained transformation in response to major shifts in living standards, lifestyles and mobility habits.

Battery lab

EVs are clearly to the forefront of these trends, as evidenced by developments at Arlanxeo which has upgraded its battery technology lab facility in Changzhou, China to support its R&D in the field of energy-storage for new-mobility applications.

The project at Arlanxeo’s regional technical centre features the addition of a new ‘pouch cell’ line for developing rubber solutions in lithium-ion batteries.

According to the Dutch-based synthetic rubber major, the line will enhance local R&D capabilities and reinforce its commitment to introducing advanced applications for new-energy technologies.

With the new facility, placed in an ultra-dry (<0.1% relative humidity at 23?C) space, Arlanxeo said it can now simulate industrial battery manufacture of soft pack lithium-ion batteries.

The upgrade, it explained, will also enable the company to evaluate battery performance and quality according to application needs.

Furthermore, Arlanxeo can now better assess production requirements of certain ‘high nickel’ materials, as the upgrade allows for testing of all-solid-state batteries.

“This can support the development of batteries with better energy-density, safety and sustainability,” said the company’s statement.

Such batteries can be used for vehicle power batteries, small power batteries for two-wheeled vehicles, digital batteries, and other applications.

Arlanxeo went on to describe the investment as “a direct response to the new-mobility market demand for innovative elastomer solutions.”

Alongside meeting increasing demand for high-end batteries in EVs, the company noted that China remains “one of our most important strategic markets.”

“With our newly upgraded battery lab, we are in a position to add value to our customers through the co-development of cutting-edge battery solutions,” said Hong Sun, managing director, Arlanxeo China.

In addition to the upgrade, Arlanxeo said it is increasingly collaborating with customers to develop improved thermal management capability and improved noise and vibration control.

“We are confident that our upgraded lab will lead to advancements in new mobility applications,” said Herman Dikland, chief technology and sustainability officer at Arlanxeo.

High voltage

Elsewhere, Japanese group Shin-Etsu Chemical Co. has developed a new silicone rubber for use as an insulation-covering material for high-voltage cables used in automotive vehicles.

The silicone is said to be particularly suitable for EVs and hybrid electric vehicles (HEVs), whose drive systems increasingly require higher-voltage/large-current cables.

Presently, to address the insulation requirements, layers of insulating materials are used, leading to cables becoming thick or inflexible, according to Shin-Etsu.

As such, these cables are “problematic to handle and to route through the interior of the vehicle,” the Japanese group explained in a recent release.

In contrast, Shin-Etsu claims its newly developed KE-5641-U silicone rubber can withstand high voltages, even when the cable’s insulation layers are made thinner.

In addition, the thinner covering layers lead to a significant improvement in the flexibility of the cable, while realising a lighter weight, high-voltage cable.

The new cabling material, continued Shin-Etsu, exhibits a dielectric breakdown strength of 40kV/mm, compared to 26kV/mm for the company’s existing products.

The silicone material ‘enables B resistance to heat and cold as well as weatherability and flame retardancy,’ the company also stated.

In addition to EVs, the new product can also be used as an insulation covering material in high-voltage cables for applications such as industrial machinery, railroad equipment, and energy plants. 

‘Game-changer’ TPE

Thermoplastic elastomers specialist Kraiburg TPE is, meanwhile, unveiling what it described as a “game changer” for innovative automotive interior applications in Asia Pacific.

According to Kraiburg TPE, its new TPE series Thermolast K FG/SF/AP offers surface-quality advantages that meet growing requirements of “user-centric designs and constructions” in the region.

Offering a hardness range between 60 – 80 shore A, the new TPE series produces even surfaces with two-component injection moulding, according to the company.

Also, the elastomer materials feature good ‘surface mapping’ as well as temperature stability up to 100°C, the materials supplier further pointed out.

The series, therefore, “satisfies the demand for sophisticated automotive aesthetic appeal [allowing] refined hard-soft composite components with a high level of surface appearance and quality.”

Target applications, continued Kraiburg TPE, include handles and covers, mats, door sills, glove boxes, sealing and soft-touch surfaces within vehicles.

“TPE with low viscosity capabilities expands the possibilities for plastic part design,” Marcus Cheah, project manager of Kraiburg TPE commented in a company press release.

“They shorten the process cycle time and open up a larger processing window in injection moulding for large surfaces and thin parts,” explained Cheah, adding that the TPEs exhibit low odour and emissions, in-line with stringent automotive OEM requirements.

NVH innovations

Another challenge facing vehicle makers around the world concerns the elimination of noise, vibration and harshness (NVH) issues in the development of e-mobility platforms and powertrains.

In this arena, Vibracoustic has engineered a rubber-based solution for the problem of ‘torque ripple excitations’ caused by the fluctuating magnetic fields of e-motors in battery electric vehicles.

According to the Darmstadt, Germany-based company, its newly developed multifunctional stator isolator prevents the transmission of axial, radial and torsional vibrations from the stator into its housing.

In contemporary BEVs, torque ripples are transmitted from the e-motor to the gearbox, the housing of the e-motor and the gearbox, side shaft and into the wheel.

The effect can result in NVH-related issues, such as unwanted airborne noises, explains Vibracoustic, adding that its new design insulates the stator from the stator/e-motor housing, providing axial, radial and torsional isolation.

Designed to be integrated with e-motor cooling devices, the multi-functional product, it said, also provides an effective seal for circulating oil – an essential requirement for e-motor durability and safe operation.

Based on expertise in the development of rubber compounds, “the stator isolator withstands long-term exposure to high-temperature oil while maintaining tight tolerances,” continued Vibracoustic.

The product is designed to be adapted to the existing stator carrier, with unique form-fit geometries that prevent rotation and provide an effective and durable seal, according to the company.

Vibracoustic went on to note: “While the stator isolator is initially intended for premium segment vehicles where NVH management is paramount, there is scope to integrate a similar solution in… any vehicle using e-motors.”

“We proactively invest in the research and development of innovative new solutions to support established and emerging OEMs,” commented Dr Jörg Böcking, CTO at Vibracoustic

The stator isolator, concluded Böcking, is “an effective and forward-thinking product that demonstrates our whole-vehicle approach to NVH management and our commitment to easily integrated solutions that deliver tangible, real-world benefits.”

In another application, Vibracoustic has optimised chassis bushings for battery electric vehicles: tuning the units to handle the increased vehicle weight and higher preloads while also ensuring advanced levels of NVH performance.

As current BEVs are about 18-24% heavier than internal combustion engine equivalents, they create significant for issues around chassis-control and NVH management.

To mitigate many of the issues, Vibracoustic used advanced simulations and expertise in optimising rubber compounds to better understand the frequencies encountered, helping to mitigate them with a ‘low-hardening’ rubber compound.

Furthermore, the component designs were optimised so the overall bushing can handle dynamic load while driving as well as static preload while stationary.

‘Flush’ for Range Rovers

Land Rover has unveiled its new Range Rover and Range Rover Sport incorporating ‘flush’ glazing technology developed by structural sealing specialists at Hutchinson.

Flush is described as “a new structural sealing solution for window hidden frames [that is] lighter, easier to install and cheaper than frameless doors.”

The roll-out on the luxury Range Rover & Range Rover Sport platforms marks the initial application for the sealing technology, said the French group.

Developed to offer “unique and simple” design options, the flush system can be adapted to individual customer and market requirements, said Hutchinson.

‘Flush’ will soon be introduced to other automotive manufacturers in Asia, Europe, and the US, the supplier adding that it could also be applied in other market segments, particularly mid-range vehicles.

According to the manufacturer, ‘flush’ featured on three vehicles series launches in 2022 with on-going discussions for five further vehicles in Europe, the US and China. 

“The simplicity, in contrast to previous solutions, offers benefits in terms of cost, assembly and weight that make it the best solution in these areas,” Hutchinson claimed.

‘Flush’ is “much cheaper and easier to develop than frameless concepts, is easy to assembly and delivers CO2 reductions due to weight savings,” continued Hutchinson.

Moreover, it added, it is also possible to design a standard solution for a door, with and without ‘flush’ technology, making it possible to differentiate a range of vehicles without additional developments and investments.