Synthetic ester plasticizers

Many rubbers and elastomers are comprised of long hydrocarbon segments, and thus can accept petroleum oils and other predominately hydrocarbon products for use as plasticizer or extenders. These products are available at a significantly lower cost than the synthetic ester plasticizers. Phthalates and adipates of linear alcohols are used to enhance low temperature properties of certain rubber applications, which cannot be met using the hydrocarbon extenders. Polar elastomers such as nitrile rubber and polychloroprene have low compatibility with hydrocarbons and require more polar products such as phthalates or adipates. 

Process Oils, Synthetic Ester Plasticizers, and Processing Aids... 

When compounding general-purpose elastomers, aromatic, naphthenic, or paraffinic process oils are commonly used. However, for certain specialty elastomer compounds, the more expensive synthetic ester plasticizers must be used for reasons of chemical compatibility. 

DOA is a common synthetic ester plasticizer used in various oil-resistant compounds to improve low-temperature properties. The commercial volumes of DOA consumed by the rubber industry are much smaller than those for DOR... 

Dioctyl sebacate is another synthetic ester plasticizer that is used to help achieve better low-temperature properties for compounds based on specialty elastomers. 

Butyl oleate is a relatively inexpensive plasticizer that is used occasionally to improve processability. Considered a secondary plasticizer, it is relatively inexpensive but has limited compatibility with some elastomers. Butyl oleate can impart significantly better low-temperature properties than many other synthetic ester plasticizers. On the other hand, butyl oleate may be more volatile with less permanence. It is sometimes used in sheeting and hose applications. 

Acetaldehyde is aldolized and hydrogenated into 2-ethylhexanol to make synthetic ester plasticizers for rubber compounds based on specialty elastomers. These plasticizers include DOP, DOA, and DOS. 

Naphthalene Is oxidized to phthalic anhydride to produce DOP and DIDP synthetic ester plasticizers, which are used in specialty elastomer-based compounds. 

Sebacic acid is used to produce the synthetic ester plasticizer DOS (dioctyl sebacate), used to impart good low-temperature properties to a rubber compound. 

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... 

There are no effective low-temperature synthetic ester plasticizers with viscosities above 50 cps. 

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