Polymer producers have responded to the changing tyre industry expectations, their innovations take into account a more reactive functionality within polymer architecture, and this is closely matched by increasingly greater degrees of filler surface chemistry. As a result, tyre compound properties may now be tailored to meet quite specific tyre performance targets.

Tyre processing methods also underwent progressive stages of modernisation in recent years, for example, more sophisticated reactive mixing technology together with high-speed extrusion systems allowing for direct extrusion onto the building drum become established as cost effective production routes for many of the major producers.

These advancements however bring about their own conflicts, processing pathways involving multiple stages, often with the ability to rework compound or adjust rheological properties by additional time or energy input during the process are no longer viable options for most tyre producers. It has thus become necessary to achieve processability through an increasingly narrow operating window.

Formulations optimised to achieve peak tyre performance in most cases also tend towards more challenging processing characteristics. This is to be expected; the use of high and narrow molecular weight reactive polymers alongside fillers having high surface area and chemistry, often in loadings above that of the polymer are the norm. The trend towards usage of high loading of plasticiser and resinous materials to adjust tyre tread grip and traction response all contribute to a less forgiving processing nature. Often those compounds that are highly reinforced appear the most fragile during processing and poor green strength with an easily tearing or crumbly compound appearance are often-discussed processability issues. By contrast, the use of high loadings of resins and plasticisers, for example in winter or high-performance tyre formulations, results in compounds that during processing can more resemble chewing gum than tyre treads!

The use of process additive chemicals in an attempt to overcome the processing limitations observed gives rise to further conflicts; Lubricant additives might improve compound surface appearance; however, green strength will probably further reduce due to the unwanted softening effect. The same is true for release additives where lower tack unfortunately remains at a higher value than the also lowered tensile strength of the compound. Filler dispersion is often targeted by additives, however higher loading of fillers mandate equally higher additive loadings, we should more accurately discuss loading as “parts per hundred of filler” not rubber, and under the appropriately higher additive loading, the risk of interference with vulcanisation properties or even additive migration leading to surface bloom become realistic concerns.

Conflicting performance characteristics

The development team at Schill + Seilacher has recognised the need to decouple conflicting performance characteristics found within conventional process additive chemistries. As a result, innovation within our Struktol® range offers tyre compounders opportunities to achieve processability without compromise.

Reduced viscosity leading to better extruder flow properties and improved surface appearance, whilst at the same time achieving an increased compound green strength can be realised by use of Struktol HT 300, a new generation of reactive process additive.

An extract of key processing and property influence in a typical highly silica filled sSBR tread compound are highlighted in the following data.

Significantly lowered Mooney viscosity as well as better mixer batch off with reduced sticking to the mixer rotor and gate with Struktol HT 300 are observed.

An increase in compound green strength was obtained by the addition of Struktol HT 300; this is the opposite of expectation for conventional process additive chemistry, where reduced viscosity is obtained. In addition, the filler dispersion as evidenced by a reduction in the so-called “Payne Effect” as tested in uncured compound by means of RPA strain sweep, is also improved.

Lab extrusion trials, using cold feed extruder demonstrate improved surface appearance and lower compound pressure achieved by use of Struktol HT 300, both desirable processing conditions.      

Physical properties are also acceptable, with a progressive increase in tensile strength an elongation and maintenance of stiffness with loading of 6 phr of process additive, only at higher loading of 12 phr would a balancing slight reduction in process oil be required.

Compound hardness remained unchanged alongside improved wear resistance, as measured by DIN abrasion loss testing, even when using higher loading of process additive, are important aspects.

The ability to decouple the relationship between lubrication, important for improved rheological behaviour, and the maintenance of strength and stiffness in both the uncured and vulcanised condition is only possible with such new and innovative class of process additive. This departure from conventional thinking offers the tyre compounder significant degree of freedom to retain the benefits in terms of easier processability without sacrifice of key tyre performance properties.

In this example, the use of Struktol HT 300 prioritised green strength alongside reduced viscosity. By contrast, our new Struktol HT 250 decouples release from other properties, especially effective for winter tyre tread; compound stickiness is resolved without compromise of viscoelasticity.

Ensuring that migration and ultimately bloom within rubber compounds is kept to the lowest level is important for final article aesthetics, for tyres additional considerations arise; they are composite structures, therefore it is imperative that chemicals do not migrate across boundary layers in an uncontrolled manner, which could result in changed behaviour or interfacial adhesion failure over time. In order to limit migration, the compatibility, solubility and concentration of chemicals are carefully considered. However, one method of ensuring long-term stability involves chemically binding the additive within the vulcanisation network.

At Schill + Seilacher, we have achieved this degree of crosslinking capability for a number of new-generation Struktol process additives. Their usage allows the compounder to avoid completely the risk of migration and bloom due to additive presence.

Photographs of two vulcanised rubber sheets based on the same formulation. On the left-hand side, evidence of typical surface bloom, which may occur due to migration of a conventional process additive, on the right, containing reactive additive Struktol HT 600 as replacement, it can be seen that bloom was eliminated.

This technology also opens tremendous opportunities to “fix” process additives in place within the respective component, the role of additives withinthe cross-linking mechanism may additionally lead to vulcanisate performance characteristics.

                                                                                  One interesting tyre related example involves the development of a superior tyre curing bladder performance, here we have developed new reactive plasticisers called Struktol HT 815 and Struktol HT 820, their use is directed towards resin-cured butyl rubber. This combination of polymer and curing system provides for superior heat resistance with excellent flex fatigue resistance and is used as the basis for tyre curing bladders. Here the replacement of widely used castor oil as plasticiser with new Struktol HT 800 series product leads to a significantly improved bladder performance life, with greater stability in viscoelastic properties. Reduced stiffening of the bladder, due to lower degree of plasticiser migration translated into a much lower flex-cracking rate, especially after high temperature steam ageing.

Reactive Struktol plasticisers, HT 815 and HT 820 exhibit a significantly reduced flex cracking rate when compared to the widely used castor oil, which readily migrates from the bladder; as a result, significant extension of bladder service life is possible.

New reactive process additives, with tailored functionality to closely match the specific chemistry of polymers, fillers and cure systems are actively developed. These innovative products under the Struktol brand offer tyre compounders a more comprehensive toolkit in order to tailor compound performance to meet tyre performance demands. The conflicts of property versus processability diminish and new possibilities emerge!

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Vipal Rubber has launched the VT290, a tread designed for truck drive axles used on motorways and paved roads, targeting regional and long-distance transport operations in Europe.

The product is available in widths of 240mm, 250mm, 260mm, 270mm and 280mm. It is designed to provide traction and stability on dry and wet roads, as well as in demanding conditions involving snow.

Frederico Schmidt, General Manager of Vipal EMEA, said, “The launch of the VT290 reinforces Vipal’s ongoing commitment to offering technologically advanced solutions suited to the specific characteristics of European roads and climate.” “We want to further consolidate our presence in the region, delivering a high value-added product that combines innovation, operational efficiency and safety,” he added.

The VT290 carries the M+S marking and 3PMSF certification. Its design includes side sipes and grooves intended to help remove snow and mud from the tread, improving grip on slippery surfaces.

The tread pattern is also designed to distribute engine torque more evenly, helping to reduce uneven wear. Tie bars between the tread blocks add structural stability, supporting vehicle control during driving.

Fabrício Nedeff, Commercial Manager of Vipal EMEA, said, “With the VT290, weare responding directly to the real needs of fleet operators and truck drivers, combining performance, adherence and efficiency in different driving conditions. [RS2.1]In addition to expanding options for our customers, the product strengthens business opportunities for our partners in the region,”

Vipal said the launch would expand its offering for retreaders, distributors and fleet operators in the European market.

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The Association of Natural Rubber Producing Countries (ANRPC) published its Monthly Natural Rubber Statistical Report for August 2026, noting firmer prices in several markets. Supply constraints, stable downstream demand and persistent geopolitical and macroeconomic uncertainty shaped the month. Renewed conflict and disruptions to major shipping routes added further pressure.

Physical prices for major grades moved in different directions. SMR-20 in Kuala Lumpur averaged USD 2.31 per kg, up 4.25 percent from July, while STR-20 in Bangkok rose 1.40 percent to USD 2.39 per kg. RSS-3 dropped 4.18 percent to USD 2.80 per kg, but RSS-4 in Kottayam gained 0.57 percent to USD 2.92 per kg. Latex-in-bulk fell 4.73 percent to USD 1.73 per kg. Brent crude averaged USD 91.08 per barrel, driven by concerns over possible restrictions on oil shipments through the Strait of Hormuz and wider Middle East instability, which raised energy supply risks and strengthened the oil market risk premium.

On trade, China's imports climbed 3.39 percent month-on-month, while India fell 10.18 percent and Malaysia dropped 8.24 percent; Viet Nam rose 5.08 percent. Exports advanced 5.63 percent in Viet Nam but declined in Thailand (-5.24 percent), Indonesia (-5.36 percent), Malaysia (-1.48 percent) and Cambodia (-1.88 percent).

Global production is projected to rise 0.6 percent to 15.039 million tons in 2026 from 14.952 million tonnes in 2025, after revisions to Thailand's 2025 output and updated 2026 estimates for Thailand, Malaysia and Indonesia. Weather, including erratic rainfall and drier Southeast Asian conditions, affected output. August 2026 production was estimated at 1.396 million tonnes, down 4.51 percent from 1.462 million tonnes a year earlier. Demand is forecast to grow 0.4 percent to 15.356 million tonnes in 2026 from 15.301 million tonnes, with the largest consumption gains expected in China, Malaysia and Cambodia. Prospects depend on vehicle sales, tyre production, shipping conditions and weather-related supply disruptions, while steady EV-linked demand supported modest growth led by China and India. The ringgit traded between RM4.02 per USD and RM4.09 per USD, and the baht between 32.68 and 33.34. The SHFE January 2027 contract averaged 18,109 CNY per tonne, up 7.78 percent month-on-month, while the SGX November 2026 contract averaged USD 2.24 per kg, up 4.32 percent.

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Epsilon Carbon Pvt. Ltd., a global speciality carbon and carbon black manufacturer, has broadened its emissions accounting to include value chain impacts beyond its direct operations. The move advances measurement and management of Scope 3 emissions across its supply and distribution network, according to the company.

The initiative spans Epsilon Carbon’s integrated carbon complex in Vijayanagar, Karnataka. That site has a production capacity of 500,000 tonnes per annum of speciality carbon and 215,000 TPA of carbon black. It combines carbon manufacturing with energy circularity efforts in one integrated ecosystem. The company assessed material Scope 3 categories under GHG Protocol guidelines.

Scope 3 emissions are indirect and arise from purchased goods and services, transportation, business activities and downstream product use where relevant. The assessment gives Epsilon Carbon clearer visibility into emissions outside its direct control and a foundation for spotting reduction opportunities. It builds on existing operational emissions and energy efficiency work.

The company previously reported a 98 percent Scope 2 reduction against its baseline year. A 17 MW captive power plant uses waste heat from carbon black operations, energy consumption intensity fell 6 percent from baseline, and 77 percent of energy needs came from waste heat recovery, avoiding over 89,000 tonnes of CO₂. Epsilon Carbon now emphasises supplier engagement, data transparency and circularity, aligning disclosures with global sustainability frameworks to track value chain emissions consistently and develop measurable reduction initiatives.

Vikram Handa, Managing Director, Epsilon Carbon, said, “Meaningful climate action requires us to look beyond the boundaries of our operations and understand the impact of the entire value chain. Scope 3 measurement gives us greater visibility into the emissions and enables deeper engagement with our partners and suppliers. Building this visibility will help us make more informed decisions as we scale our operations and advance our decarbonization plans.”

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HS HYOSUNG has formalised a memorandum of understanding (MoU) with the State Government of San Luis Potosí, with the signing taking place at the World Trade Center Mexico City. The event formed part of the Korea-Mexico Business Forum, held alongside the Korean economic delegation's visit to Mexico.

Attending officials included Marcelo Ebrard, Mexico's Secretary of Economy, and Mario García Valdez, Secretary of Economic Development of San Luis Potosí. The two sides confirmed their shared resolve to back the company's local investment and regional growth. Separately, HS HYOSUNG's leadership met bilaterally with Secretary Ebrard to elaborate on its strategic vision and investment plans.

The agreement sets out a phased expansion of HS HYOSUNG's investments in San Luis Potosí beginning in 2027, with the goal of creating a major advanced materials production hub that bolsters supply for North American and wider global markets. The company's advanced materials span tyre cord, a flagship world-leading product, along with mobility, energy, aerospace and defence applications. Its North American operations, spanning Mexico and the United States, turn out tyre cord, airbag materials and mobility interior components for global leaders such as General Motors and Goodyear, underpinned by a highly dependable global supply chain.

Nak-yang Sung, CEO, HS HYOSUNG ADVANCED MATERIALS, said, “This investment goes beyond establishing a simple manufacturing base – it reflects our strategy to turn Mexico into a pivotal hub connecting North America with global supply networks. We are also committed to strengthening local supply chains and creating high-quality jobs to contribute directly to the region's industrial ecosystem.”

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