Reading Time: 3 minutes

Zinc oxide, known by the chemical formula ZnO, is widely used in the rubber industry as a filler to enhance the strength and resilience of rubber compounds. This versatile material provides essential properties such as temperature, heat and abrasion resistance. French process zinc oxide, in particular, is an ideal additive for rubber products. Zochem offers French process zinc oxide with high purity and excellent reactivity.

Applications for Rubber Products

French process zinc oxide can transform natural rubber into a more durable material with enhanced physical and mechanical properties. This is why 50% to 60% of its use is in the rubber industry. Applications of zinc oxide for rubber products include:

• Truck, tractor and passenger car tires
• Hoses, belts and gaskets
• Shoe soles and heels
• Rubber wire and cable jackets and insulation
• Inflatable boats
• Carpet backing
• Sports equipment
• Pressure sensitive, rubber-based adhesives, tapes and sealants

Importance of ZnO in Rubber Manufacturing

French process zinc oxide plays an important role in rubber formulations as a reinforcing agent, improving the strength and durability of rubber products. It is also the most effective activator for accelerating rubber vulcanization, a key process that improves the mechanical properties and durability of rubber materials.

Catalyst in Rubber Vulcanization

During the vulcanization process, zinc oxide reacts with sulfur to form a strong vulcanizing agent. Additionally, ZnO boosts the sulfur-based vulcanization process by activating cross-linking reactions that form strong bonds within the rubber. These bonds increase the strength, elasticity and abrasion resistance of rubber.

Improves Thermal Conductivity

Zinc oxide also enhances the heat and UV resistance of rubber. As a heat and UV stabilizer, it improves the durability of rubber under high temperatures and exposure to ultraviolet radiation from sunlight. This reduces heat buildup in tires and prevents thin films from cracking, fading or becoming brittle due to sun exposure, especially in outdoor environments.

Extends Rubber Lifespan

By improving heat resistance, ZnO protects rubber against oxidation and deterioration. It also improves rubber-to-metal adhesion and resistance to wear and tear, as well as reduces shrinkage in manufacturing. These qualities help extend the lifespan and reliability of rubber products while reducing maintenance and replacement costs.

French Process Zinc Oxide Makes a Difference

Zinc oxide produced through the French process outperforms American process and commercial blends when it comes to purity, performance and safety. Zochem uses this process to produce different grades of zinc oxide.

Starting with pure metallic zinc or recycled zinc, Zochem vaporizes and oxidizes the material in a combustion zone, using a natural-gas-fired muffle furnace. This yields consistently nodule-shaped crystals with purities of 99.9% and beyond.

In addition to its purity, French process zinc oxide features:

• Consistent quality with fine and uniform particles, important for applications requiring tight particle size control.
• Good reactivity, which helps enhance a rubber product’s physical and mechanical properties.
• An environmentally friendly process that generates minimal hazardous waste.

In its research comparing French process (FP) zinc oxide with American process (AP) zinc oxide, Zochem reported that AP performed worse than FP on Goodrich Flexometer Blowout tires. In addition, cure time with FP was ~33% better than with AP for MDR cure at 177 °C, making FP ZnO better for cycle time and production efficiency.

Zochem is the Largest Supplier of ZnO

Zochem manufactures the largest amount of French process zinc oxide globally, with various options related to particle size, purity and coatings. Its Grade 400 is ideal for use in tire and rubber applications, offering a medium particle size (0.21 m) excellent for applications requiring low surface reactivity.

This brilliant white powder is available in pellet form and with up to a 0.1% processing aid (Grade 400T) for certain rubber mixers. Pelletized zinc is ideal for production applications requiring high flow rates and low dusting.

Finding high-quality zinc oxide is easy with H.M. Royal, as we stock a full line of Zochem ZnO grades for rubber and rubber-based adhesives and sealants. We offer local delivery, technical support and competitive pricing whether you need a truckload, pallet or a 50 pound bag.

Find out more about Zochem French process zinc oxide by visiting https://hmroyal.com/zochem/.