• Plastic ( soft or malleable) at normal ambient temperatures
• A melting point above approximately 45 °C.
• A  relatively low viscosity when melted (unlike many plastics)
• Insoluble in water
• Hydrophobic

We shall be discussing here on the waxes which are only being used in the rubber and plastic industry. Beeswax, perhaps , is the first wax which used by human in the beginning of our civilization, was one of the important renewable source of fuel. The honey comb formed by bees has typical hexagonal geometric pattern (Fig.1). Bees wax is used in tire building drum, if the rubber is too sticky, it can also be used in two roll mill to take care of rubber sticking to the rolls. It is frequently being used in the BC, MC, PC, TB  inner-tube making industry during pre-forming operation in the green stage when inner-tubes are expanded under mild air pressure just before curing in mold.

The main commercial source of wax is, however, crude oil but not all crude oil refiners produce wax. "Mineral" wax can also be produced from lignite. Plants, animals and even insects produce materials sold in commerce as "wax". There are five categories of waxes being used in rubber industries :

• Bees Wax
• Paraffin Wax - made of long-chain alkane hydrocarbons
• Microcrystalline Wax - with very fine crystalline structure
• Chlorinated Paraffin Wax
• Polyethylene Wax
• Chlorinated Polyethylene Wax

The major uses of petroleum based waxes are in rubber, cosmetics and in Candle industry. They are generally white in color but show usual brown color (Fig.2) due to contaminated with oil traces. Two types of waxes, in general, are used in rubber industry, Paraffinic wax and Microcrystalline wax. Its normal dose is 1-3 phr and high level of wax impairs low temperature flexibility and compression set. Rubber compounder considers wax as a very important processing aid because it has following advantages:

• Improves mixing properties

  

   

• Improves dispersion of filler and other ingredients
• Improves extrusion properties
• Improves upon extrudate and calendared surface finish
• Protects surface and acts as antioxidant /antiozonate

Paraffin and Microcrystalline waxes are derived from petroleum. They are easy to recover and offer a wide range of physical properties that can often be tailored by refining processes. Most producers offer two distinct types of petroleum waxes: paraffins, which are distinguished by large, well formed crystals; and microcrystallines, which are higher melting waxes with small, irregular crystals. Microcrystalline wax contains substantial proportions of branched and cyclic saturated hydrocarbons in addition to normal alkanes.

Some producers also sell "intermediate" wax, in which the boiling range is cut where the transition in crystal size and structure occur. Petroleum wax producers also characterize wax by degree of refinement; fully refined paraffin has oil content generally less than 0.5% and fully-refined micro-crystalline less than 3%. Paraffin wax produced from petroleum is essentially a pure mixture of normal and iso-alkanes without the esters, acids, etc. found in the animal and vegetable-based waxes.

Paraffin wax (or simply "paraffin") is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 47-64 °C  and having a density of around 0.9 g/cm³. It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents, but burns readily. Paraffin wax is generally unbranched hydrocarbon having carbon above C₁₇ and  are solid at room temperature. Their carbon atoms typically ranges between C₁₇ - C₃₀ and having typical melting point around 60°C. All paraffinic wax are recovered from fractional distillation of petroleum.The name paraffin implies that it contains straight hydrocarbon structure but it has branch also. Branched paraffins are called ‘Isoparafins’ and cyclic parafins are called ‘Cresines’ or ‘Isoceresies’.

Pure paraffin wax dose in rubber compounding varies from 1-3 phr. Pure paraffin wax is rarely used these days in rubber industry as it has oozing character and in excess it causes blooming on green rubber components, that results in reduction in compound tack. They are frequently blended with microcrystalline wax in rubber compounding therefore.

Pure paraffin wax is an excellent electrical insulator, with an electrical resistivity of between 10¹³ and 10¹⁷ ohm meter. This is better than nearly all other materials except some plastics (notably teflon or polytetrafluoroethylene). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron. Paraffin wax (C₂₅H₅₂) is an excellent material to store heat, having a specific heat capacity of 2.14–2.9 J g^–1 K^–1 (joule per gram per kelvin) and a heat of fusion of 200–220 J g^–1(joule per gram). This property is exploited in modified drywall for home building material.

Microcrystalline waxes: This is produced by de-oiling petrolatum, as part of the petroleum refining process. Microcrystalline wax contains a higher percentage of isoparaffinic (branched) hydrocarbons and naphthenic hydrocarbons. It is characterized by the fineness of its crystals in contrast to the larger crystal of paraffin wax. It consists of high molecular weight saturated aliphatic hydrocarbons with comparatively higher melting point than paraffinic wax. It is generally darker, more viscous, denser, tackier and more elastic than paraffin waxes. The elastic and adhesive characteristics of microcrystalline waxes are related to the non-straight chain components which they contain. Typical microcrystalline wax crystal structure is small and thin, making them more flexible than paraffin wax. It is commonly used in rubber formulation and cosmetic formulations.

Its usual carbon atom ranges from C₄₀–C₇₀ , having comparatively higher melting point (Fig.4) between 80-105 ⁰C because they have higher number of carbon. Common dose in rubber compounding is between 1-3 phr. Some time higher dose of  100% Micro crystalline wax is difficult to process and as a result they are often blended with paraffinic wax for rubber use. Blending is also done for economical reasons as microcrystalline wax is comparatively costlier. Paraffinic wax, having smaller molecular weight bleeds faster in cured rubber article, whereas, 100% micro crystalline wax  will have inherent resistance to faster volatilization and eventually, blended wax will have an intermediate property. Refineries may also utilize blending facilities to combine paraffin and microcrystalline waxes. This type of activity is prevalent especially for industries such as tire and rubber industries.

Higher dose of antioxidant and anti ozonates are always advised to add along with microcrystalline wax because the later help slower migration of antioxidant and antiozonates on the product surface and thereby increase on the product durability against ageing process. Tire curing bladder is often blended with 1-3 phr of microcrystalline wax.

Chlorinated Paraffin Wax

Upon chlorination of paraffinic wax we get Chlorinated Paraffin Wax(CPW). This is available in batch process that is processed from effective exothermic reaction. This reaction generates a by-product hydrochloric acid that is later removed out of the solution. Finally stabilizer and solution is mixed that provide the required final product, which is used in various industrial applications. With 30 to 70% chlorine and insolubility in water, these CPWs have low vapor pressure. Chlorinated Paraffin Wax is highly inert, insoluble in water and they have low vapor pressure. Generally used as plasticizers in plastic and elastomers, where flame retardant property is important.

Polyethylene waxes (PE-Wax)

Polyethylene waxes or PE-Wax is same familiar polyethylene chemical structure (Fig.5) but with lower molecular weight , generally around or less than 3000.This is a processing aid in elastomer and plastics but basically they are a form of synthetic resins. It is a white solid product (Fig.6) appears in the market as powdery, lumpy, or flaky product. It is a non-toxic product having concentrated distribution of molecular weight of 1500 with specific gravity about 0.94 with high softening point but low fusion viscosity with melting point; 112 - 118°C, melt peak 110 °C, flash point 210°C, minimum. It has excellent stability against polishing, scratch resistance, metal mark resistance, scuff resistance. PE-Wax is resistant to water and chemical materials.

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The Rubber Board of India has announced the opening of an application window for financial aid for sulphur dusting to combat powdery mildew disease in rubber plantations for the year 2026. The scheme is open to all Rubber Producers’ Societies (RPS) operating in both traditional and non-traditional growing regions.

From 10 to 20 February 2026, eligible societies must submit their applications online through the 'ServicePlus' portal on the official Rubber Board website. Societies requiring help with the submission process are advised to contact their nearest Rubber Board regional office or field station, or to consult the board's website for further guidance.

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Pyrum Innovations AG has welcomed the official recognition by French authorities on 17 January 2026, which classifies tyre pyrolysis oil (TPO) as a legitimate raw material for the chemical sector. This pivotal regulatory milestone for pyrolysis oil derived from end-of-life tyres substantially enhances the product’s integration into established chemical value chains. It also provides greater predictability for future purchase and partnership frameworks, thereby accelerating the development of industrial material cycles.

For Pyrum, which processes scrap tyres through pyrolysis to recover pyrolysis oil, industrial carbon black and steel, this decision underscores the critical need for standardised and reliable regulatory conditions. Such clarity is fundamental for scaling investments, production volumes and supply chains, particularly as the chemical industry and circular economy converge. The establishment of clear product categories is essential to ramp up the market for high-quality recycled raw materials.

The company remains committed to tracking further developments in France and the wider European dialogue regarding the classification and application of recycled feedstocks. Pyrum’s overarching objective is to expand industrial-scale recycling solutions for scrap tyres. This regulatory progress directly supports the company’s mission to secure long-term, quality-assured supply agreements with partners across the chemical industry, thereby advancing a more sustainable and circular economic model.

Pascal Klein, CEO, Pyrum Innovations AG, said, “The decision in France is an important step for the industrial use of pyrolysis oil from waste tyres. It supports a trend that we are seeing in many markets, where the chemical industry is seeking reliable, technologically robust and clearly classified alternative raw materials.”

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In pursuit of its strategic vision, ‘Michelin in Motion 2030’, Michelin is expanding into high-value adjacent markets, including the development of its Polymer Composite Solutions. A key step in this growth is the acquisition of Flexitallic, a global leader in sealing solutions based in Houston, Texas. This move is set to substantially enhance Michelin’s sealing portfolio and extend its market access, particularly within the aftermarket sector.

Flexitallic serves critical industries such as energy and chemicals, providing high-performance gaskets, sheet products and specialty filler materials known for exceptional reliability and resistance in extreme, safety-critical environments. The company, which operates 17 facilities worldwide and employs about 1,200 people, reported sales of approximately USD 220 million in 2025.

The acquisition is a strong strategic fit, uniting two global organisations with a shared commitment to innovation and quality, thereby creating significant synergies for future growth. The transaction, for an undisclosed amount, will be fully financed from Michelin’s available cash. Subject to standard regulatory approvals and closing adjustments, it is anticipated to be finalised in the first half of 2026.

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Birla Carbon has inaugurated a dedicated production line at its Trecate, Italy facility, specifically engineered for the finishing and packaging of its Continua Sustainable Carbonaceous Material (SCM). This industry-leading circular material is produced from end-of-life tyres, and the new line enables its manufacture in large, consistent volumes. This expansion directly strengthens long-term supply security for the company’s worldwide customer base.

The Continua SCM range, including the 8000 series for tyres, rubber goods and plastics, provides a scalable sustainable solution. It allows customers to increase recycled content while gaining functional benefits such as blending flexibility and lower homologation costs. Importantly, it delivers assured regulatory compliance and consistent quality, supporting industries in their transition toward enhanced product circularity and reduced environmental impact.

John Loudermilk, President and CEO, Birla Carbon, said, “This is a pivotal moment for Birla Carbon. Continua SCM represents the most consistent, high-quality, circular material in the carbon black industry today and replaces a portion of carbon black in most rubber and non-rubber applications. It also reflects cross-industry collaboration for sustainability, with raw material sourced from our partner Circtec’s newly launched tire pyrolysis facility in the Netherlands and finished and packed at our state of-the-art processing line in Trecate. The launch of this line is a key milestone in our ambition to put back into industry 300,000 tonnes of end-of-life tyres annually by 2030, contributing to our aspiration to achieve net zero carbon emissions by 2050.”

John Davidson, Chief Sales, Marketing and Sustainability Officer, Birla Carbon, said, “The launch of the Continua SCM processing line in Trecate ramps up the availability of our circular product portfolio for customers globally. Continua SCM enables our customers to increase the use of sustainable materials in their products while maintaining the performance standards they expect. This expansion reinforces our commitment to supporting customer sustainability goals at scale.”

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