Rubber Process Oil (RPO)

Description of Rubber Process Oil

Rubber process oil (RPO) comes in the form of synthetic and non-synthetic (also known as natural rubber process oil). They are commercially used as a component in a mixture of rubber compounds to produce rubber products such as tires, rubber bands, hoses, toys or any other rubber product. 

Rubber process oil (RPO) is an oil composition with a kinematic viscosity from 20 to 50 centistokes at a temperature of 100 degC. This value depends on the type of RPO where heavier RPO will have higher kinematic viscosity compared to ligher ones. Their flashpoint is around 215 degC and have a density somewhat similar to that of water, which is around 1.01 SG at 15 degC.

Typically, polynuclear aromatic compounds is used as a process oil for rubber compounds, especially for aromatic rubbers. Our RPO are compatible with aromatic rubbers as well but contains less polynuclear aromatic compounds than conventional aromatic RPO, which is less toxic. Most high quality rubber products are produced using RPO that contains less polynuclear aromatic compounds.

 For more information on rubber process oil (RPO), please click here. 

Main use of Rubber Process Oil

RPOs are used as a component in rubber formulations for the manufacturing of rubber products. Such products are tires, rubber bands, hoses, rubber shock absorbers, footwears, wire and cable coverings, flooring materials, solvents in the production of adhesives, sealants, polishes and many more. 

  • Automobile Tires
  • Rubber shock absorbers
  • Footwear
  • Industrial Hoses
  • Wire and cable coverings,
  • Flooring materials and carrier fluid
  • Solvent in the manufacture of adhesives
  • Sealants
  • Polishes and carbon black

Types of Rubber Process Oil

Aromatic Oil

In terms of organic chemistry, aromatic hydrocarbons are characterized by the presence of sigma bonds and delocalized pi electrons between carbon atoms forming a circle. Benzene is the simplest form of aromatic hydrocarbon and have the configuration of six carbon atoms forming a circle. 

RPOs from aromatic furfural extract are procured from selected refineries and are blended to meet stringent specifications to be used for compounding batches to manufacture tires, lactics, tubes, tire re-treading materials, engine beltings, hoses, battery casings and containers. Furfural extract RPOs have good color stability, solubility, and thermal stability.

Paraffinic Oil

This category of hydrocarbons constitutes branched chain or straight linked hydrocarbon molecules of various viscosities. Because the chain length will increase, the viscosity will increase, and also the rubber process oil becomes a lot of viscous. They find extensive usage in ethylene-propylene rubbers.

These are more stable and have the highest flash purpose for a given viscosity. This class of hydrocarbons constitutes branched chain or straight linked hydrocarbon molecules of various viscosities. As the chain length increases, the viscosity increases and the RPO becomes more viscous.

Naphtenic Oil

Naphtha is a category of hydrocarbons conjointly referred to as ‘cycloparaffins’. Although their structure is similar to the aromatic ring, these are single bonded so having a stable structure.

Many such hydrocarbon rings are also linked, indicating a range of available grades. Their unique color stability, solubility, and good thermal stability make them ideal for molded articles, slippers, LPG tubes, floor tiles, etc. Naphthenic are a class of hydrocarbons also referred to as ‘cycloparaffins’. Though their structure is similar to the aromatic ring, these are single bonded thus having a stable structure.

Technical Data for Light RPO

PropertiesUnitRangeTest method
Kinematic viscosity @ 100 °CcSt20-30ASTM D-445
Flashpoint°C200-230ASTM D-92
Density @ 15 °CSG1.01D-4052
Aniline point°C30-40IP-2

Technical Data for Heavy RPO

Heavy RPOUnitRangeTest method
Kinematic viscosity @ 100 °CcSt30-50ASTM D-445
Flashpoint°C240ASTM D-92
Density @ 15°CSG1.02D-4052
Aniline point°C30-40IP-2