Dioctyl phtalate

Processing behavior of fluoroelastomers can be improved by the addition of small amounts of plasticizers and processing aids. High-molecular-weight hydrocarbon esters, such as dioctyl phtalate (DOP) and pentaery thritol stearate, are effective plasticizers in fluoroelastomer compounds. Lower-molecular-weight esters also soften... 

DBP measurements are surprisingly reliable and can be easily and quickly obtained. Nevertheless, DBP measurement can be sensitive to surface chemistry, and values obtained with fillers of different nature can t be directly compared. For silicas, dioctyl phtalate can also be used instead of DBP [14]. 

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