Aromatic process oils

Aromatic process oil has been used in high volume with general-purpose elastomers such as SBR because it is relatively inexpensive and very effective in improving processability, especially for those compounds based on SBR. 

Solvent extraction with phenol or cresol or furfural 

Since these aromatic extracts are byproducts of paraffinic oil production, historically these aromatic streams have been significantly less expensive. 

Aromatic oil Aromatic process oil Aromatic extender oil Very aromatic oil Highly aromatic oil 

ASTM D2226 classifies petroleum process oils used in rubber compounding. This system of classification is based on the test results from ASTM D2007, a column chromatographic method called clay-gel analysis. This procedure classifies an oil on its content of saturates, aromatics, and polar compounds, as well as asphaltene content. Under this classification system, very aromatic oil is designated Type 101 while aromatic oil is designated Type 102. 

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Stan-Flex LV Aromatic processing oil Harwick Chem. 

The synthetic rubber industry uses a number of hydrocarbon additives, specifically called process oils (to act as a plasticiser, used below 20 phr) or extenders (used to keep the costs down). There are a wide range of mineral oils used as process oils, produced by blending of crude oil distillates and these may be either paraffinic, naphthenic or aromatic. Process oils containing polycyclic aromatic hydrocarbons, are classified as potential carcinogens (and their use is decreasing considerably). 

Polybutene and polyisobutylene - are the most frequently used plasticizers. Paraffinic, naphthenic, and aromatic process oils are also used. Esters of fatly acids and phosphates are also used but are less common. ... 

Oil that serves as a temporary or permanent component of a manufactured product. Aromatic process oils have good solvency characteristics their applications include proprietary chemical formulations, ink oils, and extenders in synthetic rubbers. Naphthenic process oils are characterized by low pour points and good solvency properties their applications include rubber compounding, printing inks, textile conditioning, leather tanning. 

Figure 1.15 Gel permeation chromatographs of the aromatic processing oil (solid line) and...

Figure 1.16 LAMMA 1000 spectrum of Compound 4, the carbon-black filled, vulcanised rubber compound containing the aromatic processing oil, Sundex 8125 Reproduced with permission from Waddell and co-workers. Rubber Chemistry and Technology [64]...

LD-MS has proven a uniquely useful technique for the direct characterisation of ruhher-compound surface species. Mass spectra were obtained for intact molecular ions (M+) of organic chemical rubber additives such as the aromatic processing oil, and the aromatic antiozonant and antioxidants incorporated to protect the rubber. MW information from... 

Aromatic process oils that may still be used in the rubber industry (nontire use) are derived from the aromatic extracts from paraffinic oil production see Figure 9.1. 

Proprietary rosin oil blends are used mainly in the tire industry and in belting as a less expensive alternative to using more expensive phenolic tackiflers with aromatic process oil. Rosin oil functions both as a tackifier and as a processing oil for rubber compounds usually based on general-purpose elastomers. As discussed earlier, environmental concerns are now associated with the use of aromatic oils. 

Phenol is sometimes used in solvent extractions to separate raffinate from petroleum, resulting in aromatic process oil. 

Table 12.6 has the ASTM D 2226 Classification and also shows the limits for classifying process oils by VGC. All aromatic process oils must be labeled as potential carcinogens. Paraffinic types and treated naphthenic do not need to be labeled. There is a growing availability problem with naphthenic process oils due to a shortage of naphthenic-rich crude and the exit of producers not able to justify the capital cost of solvent or hydro-treatment. This will result in increases in the cost of naphthenic oils for use in the rubber industry in the near future. 

Synthetic ester plasticizers are rarely recommended for SBR compounding. Process oils with medium to high aromatics content are quite compatible and much lower cost. Highly aromatic process oil improves green tack. Stress-strain properties are... 

One of the most difficult elastomer families to plasticize with any confidence in the results is polychloroprene. The CR grades respond differently to plasticizers than most elastomers due to the ability of polar plasticizers and aromatic process oils to attack the molecular backbone of the CR. In addition, plain unsaturated vegetable oils (e.g., rapeseed, corn, and castor), which are relatively incompatible in most specialty elastomers, are seemingly quite compatible in CR up to about 30 phr. 

PROT—with the exception of the aromatic process oils, which are labeled carcinogenic (worldwide) and the three diesters, which are currently classified as potential carcinogens (North America), compounders have little to be concerned with the impact of the plasticizer products discussed in this chapter on the environment. 

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