Natural Rubber

The distinction between natural and synthetic rubber primarily stems from their origins and chemical structures, influencing their properties and applications. Natural rubber is harvested from the latex of rubber trees (Hevea brasiliensis), where the latex is tapped and processed into rubber, known for its high elasticity, tensile strength, and resistance to abrasion, making it ideal for dynamic applications such as tires and gaskets. Synthetic rubber, on the other hand, is manufactured from petroleum byproducts through a controlled chemical synthesis process, enabling the production of diverse types tailored for specific needs. These synthetic varieties generally offer superior resistance to oils, chemicals, heat, and weathering, with types like SBR, nitrile, and EPDM being particularly effective in harsh environments found in automotive and industrial applications. The choice between these rubbers depends on the specific performance requirements, environmental conditions, and cost considerations of the application, ensuring that each type is used where it best fits in terms of functionality and efficiency.

Natural rubber is a highly elastic and flexible material with strong tensile strength and excellent abrasion resistance, making it ideal for products that undergo significant stretching and wear, such as tires, rubber bands, and various seals. It also excels in applications requiring vibration dampening, such as automotive suspension parts. However, its use is limited in environments involving oils, fats, and hydrocarbons, as these can cause the rubber to swell and degrade. Moreover, natural rubber is not suitable for extreme temperatures, as it becomes brittle in cold conditions and can soften and degrade in high heat. The suitability of natural rubber depends on balancing these properties against the specific demands of the intended application, making it a preferable choice for situations where its elasticity and durability are crucial but less so where chemical and temperature resistance are required.

Natural rubber is highly favoured for its outstanding elasticity, tensile strength, and abrasion resistance, making it ideal for numerous applications across various industries. In the automotive sector, it is crucial for manufacturing tires, belts, hoses, and gaskets due to its shock-absorbing properties and durability. It also plays a significant role in consumer goods, such as rubber bands and shoe soles, where flexibility and grip are necessary. Industrial uses include conveyor belts and anti-vibration mounts in machinery, leveraging its wear resistance and vibration dampening capabilities. In healthcare, natural rubber is used in products like gloves and catheters, although synthetic alternatives are gaining favour to mitigate allergy concerns. Additionally, its waterproofing qualities make it useful in the construction industry for materials that prevent water penetration.

At Keaflex, we recommend several moulding techniques for natural rubber, tailored to match the unique demands of each project. Compression moulding is our preferred method for its simplicity and cost-effectiveness, making it ideal for larger, less complex parts and suitable for low to medium production volumes. This technique ensures excellent control over the vulcanization of natural rubber, crucial for achieving the desired mechanical properties. For products requiring finer details or undercuts, transfer moulding offers an excellent alternative, providing enhanced control over material flow and minimising defects. For high-volume production of complex parts, we also employ injection moulding, which, though generally associated with synthetic rubbers, can be effectively adapted for natural rubber to yield consistent quality and rapid production cycles. Each method is selected based on the part’s complexity, required volume, and the specific performance attributes needed, ensuring optimal outcomes for all our natural rubber products. For more information about which rubber moulding technique would be most suitable for your project, contact us directly.

At Keaflex, enhancing the finish and precision of moulded natural rubber products involves meticulous attention to mould design, material formulation, and curing process control. High-quality moulds designed with modern CAD/CAM technologies ensure smooth surfaces and precise alignments, which contribute significantly to the aesthetic and dimensional accuracy of the final product. Optimal material preparation is also crucial; by selecting high-grade rubber and accurately formulating it with the appropriate fillers, plasticizers, and curing agents, we ensure even flow within the mould, minimising defects such as air bubbles and surface imperfections. Finally, precise control over the curing process—adjusting temperature, pressure, and timing—ensures proper vulcanization, enhancing the rubber’s mechanical properties without risking over-curing or under-curing. These integrated steps are key to producing natural rubber parts that not only meet but exceed our clients’ expectations in both function and form.