• 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.

Nouryon, a leading supplier of organic peroxides and a developer of organic peroxide solutions, has formally announced the completion of capacity expansion of its organic peroxides manufacturing facility in Ningbo, China.

The company's production capacity for Perkadox 14 and Trigonox 101 organic peroxide products, which are crucial components for altering polymer characteristics and crosslinking rubbers and thermoplastics, has increased to 6,000 tonnes each as a result of this capacity expansion. Furthermore, by improving the qualities of recycled polypropylene (R-PP), these solutions can also allow consumers to employ recycled polymers in applications that were previously exclusive to virgin plastics.

Alain Rynwalt, Senior Vice President – Performance Materials, Nouryon, said, “Nouryon is a world leader in essential ingredients for the polymer industry and this expansion highlights our dedication to supporting our customers’ growth across the entire polymer cycle. Customer interest in improving the properties of recycled polypropylene continues to rise, in line with increased consumer awareness and more stringent regulations.”

Sobers Sethi, Senior Vice President – Emerging Markets and China, Nouryon, said, “Asia Pacific is a key region for Nouryon and our most recent expansion in China strengthens our supply position even more in this growing region. Our customers rely on our existing network of manufacturing facilities and innovative technologies, and we are pleased to build more capacity to meet growing customer demand around the world.”

Trinseo, a speciality materials solutions provider, has signed agreements to supply its polycarbonate technology license as well as all proprietary polycarbonate production equipment in Stade, Germany to Deepak Chem Tech Ltd, a wholly owned subsidiary of Deepak Nitrite Limited, a diversified chemical intermediates company based in Vadodara, Gujarat, India.

The combined deals are worth USD 52.5 million. Subject to significant milestones, the business anticipates receiving around USD 9 million by the end of 2024 and an additional USD 21 million in the first part of 2025. The firm has made the decision to leave Stade, Germany, with this disposal of the production assets.

Frank Bozich, President and Chief Executive Officer, Trinseo, said, “While Trinseo recently announced its decision to exit virgin polycarbonate production, our polycarbonate technology is highly valued and the manufacturing equipment in Stade, Germany, can be utilised in India by Deepak. These are the initial steps of a strategic, collaborative partnership with Deepak, as we explore additional opportunities to leverage our technology portfolio and expand in higher-growth areas such as India.”

China's butadiene exports have experienced significant growth in recent years, particularly in 2021 and 2024. According to Sublime China Information (SCI), this surge is primarily driven by supply constraints in key regions, including the US and Southeast Asia.

Export Volume and Price Trends

In 2021, China's butadiene exports reached a historic high due to a supply gap in the US market. According to SCI, this trend continued in 2024 as reduced deep-sea cargo shipments and production challenges in Southeast Asia further tightened global supplies. From January to September 2024, China's total butadiene exports surged by 111 percent year-over-year to approximately 120.8 kilo tonnes.

The average export price of butadiene has fluctuated over the past five years. In 2023, weak demand in South Korea and competition from deep-sea cargoes led to a significant decline in export prices. However, in 2024, supply shortages from key regions drove prices to a five-year high. As of September 2024, the average export price reached USD 1,391 per metric ton, a 35 percent month-over-month increase, added SCI.

Export Destinations and Regional Dynamics

The majority of China's butadiene exports are directed to South Korea and Taiwan. In 2024, South Korea accounted for 74 percent of total exports, a significant increase from the previous year. This surge was driven by factors such as limited domestic supply and increased demand for spot butadiene.

While China's butadiene exports have been strong, the long-term potential for significant growth in deep-sea exports remains limited due to established supply chains and regional demand dynamics. Most of China's exports are currently concentrated in Northeast Asia, with limited opportunities for expansion into other regions.

Future Outlook

SCI added that 2025 China's butadiene supply is expected to be relatively sufficient, and export volumes may increase further. However, the sustained growth of exports will depend on various factors, including downstream demand in key markets, the availability of deep-sea cargoes, and the development of new production capacities in other regions.

Despite these uncertainties, China's butadiene industry is well-positioned to capitalize on global supply-demand imbalances and continue to play a significant role in the global market.

Cabot Corporation, a global speciality chemicals and performance materials company, has announced through an official statement that it will raise prices globally for carbon black products sold by its speciality carbons business. The price rise will be global and will come into effect for all shipments on or after 1 December 2024, or as contracts allow.

The company claims that the price rise is necessary owing to the impact of inflation on labour, maintenance and other production activities, as well as supply chain-related expenditures. The price increase will vary depending on the product and region.

The statement further elaborates that these price adjustments will help the company remain a dependable, long-term provider of high-quality products and services to its consumers. Cabot also underlined its commitment to guaranteeing supply security and the best service standards for its clients, as well as providing technological and process improvements and moving forward with its environmental goals.