NR (Natural Rubber)

Overview

Natural rubber (NR), derived from the Hevea brasiliensis tree — a crop grown extensively in Malaysia — is the original engineering elastomer and remains one of the most versatile. Its defining characteristic is outstanding resilience: it absorbs and returns energy very efficiently, giving it exceptional dynamic fatigue resistance and making it the dominant choice for vibration isolation mounts, bearings, and continuously flexing seals. Natural rubber provides excellent tear strength, good low-temperature flexibility, and very high elongation at break. Its limitations are susceptibility to oils, fuels, and UV/ozone — environments where synthetic rubbers are preferred. As a product grown abundantly in the region, NR is widely available and cost-effective.

Working properties

• Resilience and dynamic fatigue resistance

  Natural rubber has the highest resilience of any common elastomer — it stores and returns energy efficiently with minimal heat build-up. This makes it the preferred material for vibration mounts, anti-vibration pads, and bearings subjected to repeated dynamic loading. Synthetic rubbers typically generate more heat under the same dynamic conditions.

• Tear strength and elongation

  NR provides very high tear strength and elongation at break. Parts made from natural rubber can deform significantly without tearing — important for sealing applications where the elastomer is required to conform to irregular surfaces.

• Low-temperature performance

  Natural rubber retains flexibility at low temperatures better than many synthetic rubbers, making it appropriate for refrigeration applications and cold-climate machinery where a synthetic alternative might stiffen excessively.

• Oil and fuel resistance

  Natural rubber has poor resistance to petroleum-based oils, fuels, and greases. In any oil-contact environment, NBR or Viton is the appropriate choice. Confirm that the application does not involve oil contact before specifying NR.

• Ozone and UV degradation

  NR is susceptible to degradation by ozone and UV light — it develops surface cracks when exposed outdoors over time. For outdoor or ozone-rich industrial environments (near electrical equipment), EPDM is a better choice.

Typical uses

• Anti-vibration mounts, isolation pads, and vibration damping components
• Conveyor belt covers and impact-absorbing rubber lining
• General-purpose rubber sheet for gaskets, matting, and padding
• Flexible couplings and mechanical anti-vibration applications
• Low-temperature seals and gaskets

Things to confirm before ordering

• Hardness — natural rubber sheet is available in a range of Shore A hardnesses; confirm the required hardness for your application.
• Oil exposure — confirm no oil or fuel contact; if present, specify NBR instead.
• Outdoor or ozone exposure — for outdoor or UV-exposed applications, EPDM is more appropriate.
• Colour — natural rubber is typically brown or black; confirm if appearance matters.

How does NR (Natural Rubber) compare?

• SBR →

  SBR (Styrene Butadiene Rubber) is a synthetic alternative to NR, often used as a lower-cost replacement for general-purpose sheet. SBR has similar limitations to NR in oil and ozone environments and slightly lower dynamic properties.

• EPDM →

  EPDM offers much better ozone, UV, and weather resistance than NR. For outdoor or weathering applications, EPDM is the preferred choice. NR is better for dynamic fatigue and resilience.