Elastomers for Sustainability - New Top 10 rankings

Techsyn

Project: New tire technology platform for improved sustainability performance

With the Elastomers for Sustainability (E4S) initiative, the main goal is to identify materials science-based R&D projects that could significantly improve the environmental performance of the elastomers/rubber industry, and then track the progress hopefully right through to full-scale commercialisation – not an easy task, especially where developments for the often-secretive tire industry are involved.

Back in July 2021, Techsyn topped the E4S table with its development of a tire technology platform combining optimised synthetic rubbers from Arlanxeo with tailor-made silica from Solvay and improved mixing technology from Bridgestone.

Targets then included mass production of a summer tire with up to 30% improved wear properties and 6% lower rolling resistance than conventional equivalents, while maintaining other performance parameters.

Now, according to recent press releases from Bridgestone, the Techsyn platform has hit the road with the incorporation of the tire technology in a commercial tire compound.

Bridgestone’s new Turanza 6 tire employs “cutting-edge and sustainable” Techsyn materials along with other related technologies to improve fuel-efficiency, wet-handling and durability, while also reducing tire weight.

Use of Techsyn along with Enliten light-weighting technology for the first time ever on a Bridgestone replacement tire is stated to deliver “best-in-class tire performance with a step-change towards sustainability compared with previous generations.”

The launch of the Turanza 6, therefore, seems to represent a breakthrough for a technology highlighted in its early stages within the E4S programme.

Synthos

Project : Extending the EV tire magic triangle with multi-functionalised S-SBR

From its update provided for E4S VII, Synthos is clearly pushing ahead with its Sprintan 918S project and is “actively developing” a next generation of multi-functionalised S-SBR “with further enhanced interaction between the polymer and surrounding filler particles.” The next generation S-SBR “will enable continuous improvements in rolling resistance and enhanced wear performance”

The technology presented focuses on the use of a silica filled S-SBR rubber with a different ratio of styrene and vinyl groups than contained in the benchmark S-SBR, with the ability to improve magic triangle properties. It can be used in state-of-the-art compounding and extrusion facilities.

Judging comments

The product seems recently arrived in the market and under investigation by many tire makers. A cost comparison between normal S-SBR and Sprintan 918S is missing: it performs better, but how much more cost effective is it?

In terms of application and performance, Synthos make a good argument on how their material contributes a more sustainable future (improved fuel efficiency, reduction of CO2). In term of production, it is not clear (from this entry) if their new S-SBR is derived from 1st or 2nd generation biomasses.

Additional analysis that needs to be considered is recyclability: highly engineered materials often tend to have very complicated structures.

UPM Biochemicals GmbH

Project: Renewable functional fillers (RFF) for a lighter and more sustainable future 

In its latest update, UPM has provided comprehensive details about the progress of its project to produce lignin-based alternatives to carbon black fillers in rubber compounds. 

Official start-up of the biorefinery is now planned for the yearend, with production ramp-up set for early 2024 – about a year later than originally scheduled.

First deliveries of wood from sustainably managed regional forests arrived on site at end of November 2022 and commissioning of wood handling area has started.

Meanwhile, UPM has continued to expand the customer base and global supply-chain, while also developing end-use applications for the product.

For further details see ERJ’s print and online coverage of the E4S VI programme. 

Judging comments

An interesting innovation is UPM’s “My Biochem” tool, designed to allow customers to calculate the CO2 footprint of their compounds and provide RFF technical support.

On the commercialisation front, UPM has signed RFF supply agreements for 2024 with strategic partners and distributors.

Cabot Corp.

Project: Evolve sustainable solutions

Evolve is Cabot’s technology platform is designed to deliver reinforcing carbons in three sustainability categories: Recovered carbon black from end-of-life tires; reinforcing carbons made from renewable materials; and reinforcing carbons made with a demonstrably reduced greenhouse gas footprint from decarbonisation technologies.

The key technical (and commercial) challenge addressed by this project is that “while many innovative solutions have been introduced to industry, offering sustainable content with reliable performance at industrial scale has been difficult.”

To date, Cabot has launched two Evolve products under the recovered category: Vulcan 7H-C circular reinforcing carbon and Sterling SO-RC110 circular reinforcing carbon.

Made from ISCC+ certified tire pyrolysis oil derived from ELTs, Vulcan 7H-C is said to deliver “optimal dispersibility and extrusion characteristics to rubber compounds and drop-in performance comparable to Vulcan 7H carbon black or ASTM N234 carbon black.”

It is suitable for synthetic and natural rubber-based tire treads and industrial rubber products that require excellent wear resistance, such as conveyor belts, solid tires, and other applications that require high abrasion resistance.

Produced via a Cabot co-pelletisation technology, Sterling SO-RC110 is a semi-reinforcing material containing 10% recovered carbon material, It combines ISCC+ certified recovered carbon material with Sterling SO carbon black to deliver performance comparable to ASTM N550 carbon black.

It is said to offer high levels of quality, consistency and processability in rubber compounds used in sidewalls and under-tread compounds in passenger car and light truck tires as well as industrial rubber products.

Going forward, Cabot is developing additional reinforcing carbon technologies recovered from ELT products, which “will offer reliable performance at industrial scale, enabling tire makers to use higher amounts of sustainable content in their tire designs.”

Cabot is also collaborating with IFF Health and Biosciences to develop rubber reinforcing additives based on IFF’s engineered polysaccharide, via enzymatic polymerisation of sustainable European sugar beets.

Cabot added that Evolve “represents a significant portion of its R&D spend, with the goal that 100% of our product and process development projects will have a sustainability benefit by 2025.”

Judging comments

Cabot’s entry into the recovered carbon black (rCB) and related sustainability arenas could make a real difference. Evolve, the company stated, “represents a significant portion of Cabot’s R&D spend, with the goal that 100% of our product and process development projects will have a sustainability benefit by 2025.” Would be good, though, to have more visibility about what happens next…

The entry focuses on two carbon blacks derived from tire pyrolysis oil, but more details are needed about the recovered carbon material and why 10% only? Further detail and comparison about the different types would also be useful. The two recovered CBs are well described, but would help to see details about the other two mentioned categories: biomass and carbon capture & sequestration.

Asahi Kasei Europe

Project: New selectively hydrogenated SBR for reduced 6PPD usage

Asahi Kasei previously reported on the enhanced ozone resistance of its selectively hydrogenated styrene-butadiene rubber (HSBR) and its ability to allow reduced usage of 6PPD (N-(1,3-dimethylbutyl)-N‘-phenyl-p-phenylenediamine) in the rubber compounds.

In its E4S VII update, Asahi explains how further studies have shown that the HSBR makes it possible, to not only reduce usage of the antioxidant/antiozonant, but also to improve mechanical properties, including fatigue resistance.

Moreover, it said, if high-cis butadiene rubber is replaced by the HSBR in a NR/BR blend, then the equivalent NR/HSBR compound showed about twice the fatigue resistance with respect to the NR/BR compound.

Both ozone resistance and fatigue resistance are important properties that govern product-life, noted the company, which is seeking suitable applications for the HSBR other than tire tread, taking advantage of the unique characteristics.

A particular target is the tire sidewall, the part of the tire that is most exposed to UV and ozone, thereby demanding exceptionally high ozone resistance – as well as being constantly subjected to cyclic stress (flexing) during driving.

Usage of the HSBR in the sidewall could eventually reduce the frequency & need of tire replacements due to degradation, said Asahi.

In terms of the commercial status, Asahi said the HSBR is “now being used and tested by many tire manufactures’ worldwide and has received positive feedback.

Asahi’s next goal is to improve the fuel-efficiency of tires incorporating HSBR in treads and sidewalls.

Judging comments

Having developed a new catalyst to selectively reduce the double bonds present in SBR – so increasing ozone resistance and allowing reduced usage of 6PPD – Asahi’s focus has shifted to improving the mechanical properties.

The chemistry can also double fatigue resistance in tire treads and could improve sidewall performance. But the project entry offers limited technical insights. Supporting data and life cycle analysis would also be helpful to show the environmental benefits during production, use and at end-of-life.

Cabot Corp.

Project: Engineered elastomer composites

Cabot describes its E2C-branded materials as pre-mixed composite solutions that are structurally different from compounds produced by conventional methods, creating options for the incorporation of novel sustainable materials and offering superior levels of filler dispersion.

The composites are engineered to improve the performance, safety and lifespan of tires while reducing the cost and enabling sustainability benefits throughout the lifecycle.

According to the company, the materials have been “commercialised by industry leaders in a wide range of tire and industrial rubber product applications.”

In its E4S VII update, Cabot reported that it had recently completed extensive fleet testing and life cycle assessment (LCA) of E2C grade DX9640, with further road-testing underway with customers around the world to validate its performance and sustainability benefits.

The grade is designed to deliver significantly increased rubber durability through high abrasion resistance and 30% higher abrasion resistance compared to a conventional compound.

In a recent on-road tire test, the grade lowered rolling resistance by more than 10% and increased tire tread durability by 12% compared to a conventional compound – thereby, reducing fuel consumption of vehicle fleets, lowering GHG and tire-wear emissions, increasing tire-tread life  and reducing end-of-life tire (ELT) waste.

Additionally, Cabot said its first-ever LCA of an E2C composite, showed that the grade can significantly reduce emissions and environmental impacts.

This year, Cabot also expanded its portfolio for use in a range of on-road commercial tire applications, including long-haul, regional, and intercity trucks and buses, commercial tire retreads, as well as protective rubber liners for industrial equipment.

Introduced in 2020, Cabot’s first E2C product was and is designed to reduce in-field failures, extend tire/compound life in the harshest environments and maximise operational uptime for OTR tires...

In terms of further enhancements, Cabot said the technology offers “the flexibility to enable the incorporation of renewable or recycled materials into tires.

Judging comments

LCA and other testing have found that these composites can significantly reduce emissions and environmental impact, by lowering rolling resistance, enhancing abrasion resistance. Would be good to learn more about the materials science and process technology behind all these property gains.

The impact on sustainability and performance is well described, with the novelty in the method of mixing where a high filler dispersion is achieved, significantly improving filler-polymer interaction. But how the materials are “structurally different” should be explained more clearly.

There is a lot of emphasis on the performance aspect and progress toward net-zero achievement. There is not much information regarding the material development itself.

Nynas

Project: Bio-based processing oil

 For E4S VII, Nynas reported confirmation of performance in all properties, including ‘taxi fleet wear test’, in a first test project with PCR winter tires, while a second tire test project for a PCR summer tire showed “promising results” vs. TDAE (wet, RRC, handling).

Other tests in applications with natural rubber and carbon black “confirm good performance vs. most used mineral oils in tire industry… not only in PCR tread applications but also in internal compounds and, for instance, in truck or agriculture tread applications.”

Meanwhile, “polymer producers continue to show interest for oil extension of E-SBR and S-SBR with the bio-oil.” Nynas also reported the achievement of ISCC PLUS certification based on mass balance approach.

For further details see ERJ’s print and online coverage of the E4S VI programme.

Celanese

Project: Thermoplastic elastomer from bio-circular feedstock

For E4S VII, Celanese entered a bio-based version of its Hytrel TPC copolyester thermoplastic elastomer, which can be used in flexible boots for automotive vehicles, foamed shoe soles, wire & cable insulation, textiles, consumer goods and medical devices.

This project centers on the replacement of standard fossil fuel-based feedstocks with a renewable feedstock for the production of Hytrel for high-volume applications in a cost-efficient, sustainable way. Meanwhile, the manufacturing facility where Hytrel Eco-B polymers are made is “exclusively sourced” with renewable electricity.

Celanese said it adopted mass balancing for Hytrel Eco-B to provide the same benefit for the environment without the cost of physical segregation – as well as gaining the ISCC+ standard for its manufacturing sites.

Further sustainability benefits stem from ease-of-adoption by customers, with the bio-based elastomers offering a drop-in replacement for standard Hytrel, without the need to re-qualify or make any changes to machinery or tooling.

According to Celanese, seven recently launched Hytrel Eco-B polymers are globally available and “have already been implemented into commercial applications in many industries” including consumer electronics, office furniture and running shoes.

Celanese said it currently has one of its monomers available from bio-circular feedstock, allowing it to produce Hytrel Eco-B polymers with up to 73% of bio-circular content allocated.

“We are about to qualify another monomer to increase the bio-circular content in Hytrel Eco -B and launch additional grades,” stated Celanese, adding that it is also certifying more plants towards further development and commercialisation of the bio-based elastomers.

Judging comments

Some good progress with the introduction of a bio-based version of Hytrel elastomers. Launched late last year, the bio-grades are now globally available and finding commercial applications. Celanese ticks several other sustainability boxes with mass-balancing and targeting of high-volume applications and the use of second-generation biomass.

The switch to bio-sourced is novel and does require a good level of research to obtain the same monomer from a different source. However, details about the process itself (cost, yield etc) are missing.  A comparison with non-biosourced Hytrel and bio-sourced Hytrel in terms of performance, gas emissions, and production cost would also be helpful.

At this stage the material is 73% bio-sourced from second generation biomasses and work is being done to increase this content. Are these biomasses enough to meet demand or are further harvesting practices required in the future?

The sustainability aspect of the material is discussed in depth but more information is needed about the process development, material performance, grade allocation to specific industry and cost comparison with non-biosourced materials.

Novoloop

Project: World’s first chemically upcycled TPU

TPUs produced via Novoloop’s patented ATOD (accelerated thermal oxidative decomposition) process have already found a number of promising applications including the newest On running shoe, branded Cloudprime.

As the E4S expert panel previously commented: “This project tackles one of the largest thermoplastics waste streams, and transforms it into a new polymer to produce a high-quality products…  giving a new valuable outlet for PE waste.”

For further details see ERJ’s print and online coverage of the E4S VI programme.

Zeon Europe

Project: Epichlorhydrin elastomers from renewable sources

Project for the commercialisation of epichlorhydrin elastomers derived from renewable sources – glycerol by-product from plant-based biodiesel production. Zeon has implemented the bio-epichlorhydrin monomer into the production of its Eco branded epichlorhydrin rubber for a range of products, particularly in the automotive sector.

For further details see ERJ’s print and online coverage of the E4S VI programme.