The ULTRASIL 4000 GR from Evonik Industries - silica that pushes modern tyre grip

Reviewed: ad hoc news Classics & Longseller desk. Edited and checked on 2026-06-28, 04:26. Details in the imprint.

ULTRASIL 4000 GR from Evonik Industries sits as a fine white powder on a lab bench, almost silky when rubbed between fingers, yet it ends up inside chunky tyre treads on SUVs and fleet cars worldwide. Drivers never see it, but they feel the quieter roll and more confident grip in rain.

What ULTRASIL actually does

ULTRASIL 4000 GR is a precipitated silica tailored for tyre compounds that aim for low rolling resistance without sacrificing wet grip. In simple terms, it helps tyres waste less energy as heat, so cars need less fuel or battery power to maintain speed.

The material is engineered to disperse evenly in the rubber mix, giving compounders a tidy balance between stiffness and elasticity. That balance is what lets a tyre feel firm in fast highway bends yet compliant enough to cling to a soaked city roundabout.

Inside the mixing room

Walk into a tyre plant mixing hall and ULTRASIL arrives in big paper sacks and octabins, ready to be dosed into internal mixers alongside synthetic rubber, carbon black, oils, and silane coupling agents. Operators watch the batch temperature and torque curves as the silica gradually binds into the matrix.

Compared with classical carbon black only compounds, ULTRASIL 4000 GR allows lower hysteresis, the internal friction that turns movement into heat. Less hysteresis means cooler-running tyres, which supports consistent performance on long motorway runs and helps keep tread blocks from smearing away too quickly.

Why tyre makers care

In the tyre industry, EU labels for rolling resistance, wet grip, and noise push manufacturers into a narrow corridor of performance. ULTRASIL 4000 GR helps them hit demanding A and B grades on rolling resistance while still matching strict braking distances on wet asphalt.

Product managers at major tyre brands speak openly about these constraints in trade interviews. A compound engineer might tweak the dosage of ULTRASIL by just a few parts per hundred rubber to shift a tyre from a "C" to a "B" label in rolling resistance without pulling it off the target grip curve.

A human face at Evonik

Evonik Industries' silica business has long been part of the portfolio shaped under the leadership of CEO Christian Kullmann. When Kullmann talks about specialty chemicals, he often highlights products that pull double duty: better performance for customers and lower energy use in the end application.

Inside the silica unit, a product manager like Dr. Anna Schneider, responsible for ULTRASIL 4000 GR in the tyre segment, spends her days between development labs and customer visits. She listens to mixing engineers who complain about dust levels or handling behaviour and feeds those insights into gradual formulation tweaks.

Everyday impact for drivers

For a driver, the influence of ULTRASIL 4000 GR shows up as subtle changes. The car coasts a little further after lifting off the accelerator, and at 120 km/h there is less humming from the tyres on concrete slabs.

On wet Friday evenings, when reflective stripes blur under the wipers, silica-rich tyres tend to brake more consistently. The compound keeps a cleaner contact patch, helping ABS systems modulate with fewer sudden lockups compared with older, purely carbon-black designs.

Limitations and trade-offs

There are trade-offs. ULTRASIL 4000 GR needs compatible silane coupling agents to unlock its full benefit, which adds cost and complexity. Some smaller tyre makers may hesitate to adopt sophisticated silica systems because they lack high-shear mixers or precise dosing infrastructure.

Moreover, silica compounds can be more sensitive to processing windows. If the mixer temperature profile is off, dispersion suffers. Tyres may then show uneven properties from batch to batch, a sobering reminder that raw material quality is only one part of the equation.

Where it fits in the portfolio

Within Evonik Industries, ULTRASIL 4000 GR sits among a family of silica grades tailored to passenger car, truck, and off-road tyres. Some focus more on wet grip, others on abrasion resistance or processing speed.

The 4000 GR grade in particular targets passenger car and light truck applications where OEMs and fleet operators chase lower CO? emissions and fuel costs over vehicle lifetimes. It supports premium summer tyres and all-season lines that must perform convincingly in mixed climates.

Stock and company context

Evonik Industries is listed in Germany, with Evonik Industries shares (ISIN DE000EVNK013) trading on Xetra in euros. Silica products like ULTRASIL 4000 GR contribute to the company’s specialty chemicals profile that investors watch for stable margins and applications tied to mobility and energy efficiency.

This article was AI-assisted and editorially reviewed. Product information without guarantee; prices and availability may change at short notice. No investment advice, no buy or sell recommendation. Stock-market transactions involve risks up to total loss.