Plasticizers are substances those are added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, or to decrease friction during its handling in manufacture.
Plasticizers are often involved in the production of plastic products/packaging, epoxy resins (coating cans for food and beverage), water pipe lining, thermal printing paper, implanted medical devices and in the production of CDs and DVDs, mobile phones, plastic food containers, eye glass lenses, drinking bottles, food packaging, dental sealants, among many others.
Fig 1. Europe's plasticizers use in 2017 Source: 2018 IHS and European plasticizers estimates
There are several general chemical families of plasticizers that are used for polymer modification. Among them, the most commonly used are listed below.
They are produced by esterification of phthalic anhydride or phthalic acid obtained by the oxidation of orthoxylene or naphthalene. Most commonly used phthalate plasticizers include: DEHP, DINP, DIDP.
Aliphatic Dibasic Acid Esters
These include chemicals such as glutarates, adipates, azelates and sebecates. They are made from aliphatic dibasic acids such as adipic acid and alcohols.
They are esterification products of benzoic acid and selected alcohols or diols.
They are produced by esterification of trimellitic anhydride (TMA) and typically C8 – C10 alcohols
They are formed by the reaction of many combinations of dicarboxylic acids and difunctional alcohols.
They are tetraesters, resulting from the reaction of one mole of citric acid with three moles of alcohol. Citric acid's lone hydroxyl group is acetylated.
They are based on epoxidized soybean oil (ESBO), epoxidized linseed oil (ELO), castor oil, palm oil, other vegetable oils, starches, sugars etc.
Includes Phosphates, Chlorinated Paraffins, Alkyl Sulfonic Acid Esters and more.