Dioctyl phthalate abbreviated “DOP”, is a widely used organic compound with the molecular formula C6H4 (CO2C8H17). This versatile compound is also called diethylhexyl phthalate (DEHP). Dioctyl phthalate, one of the most widely used emollients, is known for its low vapor pressure, high boiling point, and high molecular weight.

The synthesis of this substance is done by the phthalic anhydride reaction with alcohol (for example, 2-ethyl hexanol). Dioctyl phthalate, which is used in the production of flexible polyvinyl chloride (PVC) plastics, is an interesting and emollient material. It has good resistance to ultraviolet light and heat. It also has excellent compatibility and resistance to hydrolysis and is insoluble in water.

Applications of DOP in the world

Uses of dioctyl phthalate

Uses of dioctyl phthalate

Dioctyl phthalate is used in the manufacture of tires, PVC, cellulosic plastics, polyvinyl acetate, and polyurethane. Other uses for this material include:

  • Manufacture of synthetic leather in industries
  • Making PVC foams
  • Making Films
  • Colored adhesives
  • Polyurethane or polysulfide adhesive
  • Manufacture of cables and wires
  • Resins used in medical devices
  • Making colored and white paper
  • Manufacture of flooring and wallpaper

How is dioctyl phthalate (DOP) produced?

DOP is produced by the esterification reaction of 2-ethyl-hexanol with phthalic anhydride. It should be noted that there are two consecutive stages in this reaction. The first step in this reaction is to produce a monastery (by desalination of phthalic acid). This step does not take long and is completed quickly. The second stage is the stage in which the conversion of monoester to diester takes place.

This stage of the reaction is a reversible chemical reaction. This step is slower than the first reaction. To change the equilibrium of the reaction towards the diester, the water in the reaction is removed by targeted distillation.

It should be noted that the presence of a catalyst as well as a high reaction temperature increases the reaction rate. The temperature in the second stage, using acid catalysts, is 140 degrees Celsius to 165 degrees Celsius. This temperature will be 200 ° C to 250 ° C using amphoteric catalysts; So depending on the catalyst we use, we can have different expectations from the DOP production process.

DOP Chemical structure

DOP Chemical structure

Depending on the catalyst used, the alcohol in the reaction, and the type of process in the reaction, the percentage purity changes may vary. At the end of this reaction, dioctyl phthalate (DOP) is purified by vacuum distillation and the excess alcohol is recycled. It is good to know that this reaction cycle takes place in a completely closed system. Of course, this two-step reaction can be done in batches or a row.

Introducing different types of phthalates

Phthalates are a group of chemical compounds. These chemicals are purposefully used as additives in the manufacture of polyvinyl chloride, plastics, and many daily consumer products. Phthalates are one of the best emollients in the world. Depending on their molecular weight, they are classified into two categories: “small molecule” and “large molecule” phthalates.

Large molecule phthalates, as their name implies, have 13-17 carbon atoms in their chemical structure. These carbons make the structure of phthalates stronger. There are different types of phthalates; Each of them has special applications, amazing properties, and interesting effects on human and animal health. In Europe, the five most widely used and popular phthalates are identified by the European Chemical Bureau: DINP, Dioctyl Phthalate (DOP) or (DEHP), BBP, DIDP, and DBP.

Complete evaluation of DEHP or di (2-Ethylhexyl) phthalate

DEHP, or di (2-Ethylhexyl) phthalate, is also known as dioctyl phthalate (DOP). As mentioned, DOP is a 2-ethyl hexanol alcohol phthalate ester that is often produced by the dimerization of butyraldehyde. Butyraldehyde is also made from the synthesis of propylene.

DEHP is a plastic softener that offers good performance in a variety of applications; So it is used for many economic products such as cables, medical products (blood bags and dialysis equipment), profiles, and building materials (floors and roof membranes).

Diethylhexyl phthalate for plastisol applications has a good fusion rate, good plasticity efficiency, and functional viscosity. The amount of DEHP in flexible polymeric materials is often around 30% by weight, but can also vary.

Introduction of DOTP or dioctyl terephthalate

In today’s life, dioctyl terephthalate (DOTP) has entered the market as a supplement and enhancer of dioctyle phthalate (DOP) applications. Using DOTP is one of the most effective and best methods for disposing of polyethylene terephthalate waste. The method of making dioctyl terephthalate is also done by alcohol. DOTP derived from alcohol is one of the most widely used emollients due to its low cost. For example, it is used as a special softener to produce PVC.

DOTP emollients are additives. DOTP emollients fill the intermolecular space when added to materials. They then increase the intermolecular distance in the bonds. This reaction leads to more flexibility and elasticity in the material. By adding these emollients to the desired material, the softness, and flexibility of that material increase. It also makes it easier to produce and work with materials.

According to research and studies, instead of using polyethylene terephthalate directly in building materials, the alcohol product obtained from it is used in the manufacture of concrete.

The effect of DOTP on concrete properties such as mechanical properties, fluidity, electrical properties, etc. was evaluated using the response surface methodology. Then, in terms of the mentioned characteristics, it was compared with the additive mortar of polyethylene terephthalate concrete. The results of these studies showed that to produce concrete mortar resistant to various damages, dioctyl terephthalate should be used instead of polyethylene terephthalate.

In these studies, it was found that the electrical resistance of the tested concrete was increased by the addition of dioctyl terephthalate (DOTP). The optimal concrete of the DOTP mix has 29.90 times higher electrical resistance than the original concrete. In addition, DOTP mixed concrete has 30.3% less thermal conductivity.

This branched structure, DOTP, has many superior properties compared to other emollients. Some of these properties include high electrical resistance, non-carcinogenicity, low viscosity, low volatility, stable properties for making products, greater fluidity, and no o-phthalate.

DOTP is one of the plastic softeners due to its interesting properties and uses in industries. It is mostly used in Europe, Russia, and the United States. Used building materials are always a useful option for disposing of solid waste; Because these wastes, like WPET, have the properties of electrical insulation, chemical resistance, and thermal insulation and create in the building.

It should be noted that when the use of WPET solid waste exceeds the specified values, various problems arise. For example separation of cement structure, its decomposition, shrinkage on one side of the concrete, etc.

Dioctyl terephthalate, when used with cement paste, forms a more homogeneous mixture than WPET. DOTP mixed cement mortar, or “DOCEM”, has about 7.6 times more electrical resistance than mixed cement mortar obtained from WPET, or “WPETCEM”.

Interesting applications and advantages of phthalates

DOP Advantages

DOP Advantages

Large molecule phthalates (containing 13 to 17 carbon atoms), such as dioctyl phthalate (DOP), are odorless and colorless. Due to its good performance as well as high stability, it is primarily used for plasticizing or softening vinyl. This colorless chemical adheres firmly to the vinyl structure and does not leave the product easily and does not evaporate. It is used in many products that require long life, good performance, and high strength.

It can be used in a variety of industries, but different types of large molecule phthalates are not mutable. For example, the special properties of dioctyl phthalate or DOP make it suitable for producing an interesting product.

Manufacturers can use this to get the best results from the desired performance, reaction safety characteristics, durability and stability of the final product, and the final appearance of the product (in terms of color, texture, shape, and size).

Use of phthalates in the construction and building materials industry:

Dioctyl phthalate, or DOP, is used to make a variety of vinyl surface materials that are durable and easy to maintain. Building suspended ceilings, flexible sealants and adhesives, durable interior cladding, wallpaper making, vinyl roofing, waterproofing, flexible flooring, electrical wiring insulation, and sound insulation surfaces are DOP applications.

Use of phthalates in automobiles and aviation:

dioctyl phthalate in automotive

dioctyl phthalate in automotive

DOP softened vinyl is used in car interiors such as dashboards, interior decorations, and seat covers due to its durability, high-temperature resistance, and UV resistance. PVC coatings that are placed under the car body, help prevent corrosion and damage to car components, against water and pollution. It can also be used as rocket propulsion.

Use of DOP in the manufacture of wires and cables:

It is used in PVC insulation for building electrical wiring. For example, PVC may use dioctyle phthalate, which conducts electrical wiring for computers and televisions. Advantages of using DOP in this industry: flexibility, low-temperature performance, electrical resistance, and heat resistance.

Use of phthalates in outdoor products:

We know that dioctyl phthalate contributes to the flexible performance of PVC. This makes the final material perform well in the face of temperature changes. The material has good flexibility in cold conditions and good resistance to degradation at high temperatures. These materials are used in many outdoor products. For example water hoses, waterproof shoes, swimming pool and roof surfaces, etc.

Use of phthalates in textiles:

DOP is used as a lubricant in textiles. Also used in coated textiles; To produce waterproof suitcases and various fabrics.

Small molecule phthalates are used as solvents in various perfumes. This makes the perfumes last longer. It is also used in women’s nail polish to prevent nail polish from flaking. DOP is also used as a solvent in varnish, colorants, insect repellents, and pesticides.

Safety tips for using phthalates



Dioctyl phthalate (DOP) is expected to generate a lot of revenue in the coming days; Because phthalates and their products usually use emollients. Also, the use of this chemical has caused the growth of the global market for dioctyl phthalate in today’s life. So the main factors that lead to an increase in phthalic acid consumption can be an increase in demand from industries such as film and paper, cables and wiring, and consumer goods.

Increased demand for phthalates in developing countries, especially in Asia-Pacific, may be growing. Another factor that leads to the priority of using this substance as an emollient is the cost of purchasing dioctyl phthalate.

Its use in some applications, such as its use in medical devices and food packaging, is a reason for replacement by non-phthalate emollients. We expect this statement to be an obstacle to the growth of the global DOP market.

Are phthalates safe for human health?

Many claims have been made about the effects of different phthalates on human and animal health in recent years. Extensive scientific data on widely used phthalates provide useful information on the safety of phthalates to consumers. This helps to dispel the general confusion about the harms of phthalates.

Around the world, scientific and governmental agencies, as well as regulatory bodies, have promoted the safety of phthalates widely used in commercial products. In addition, independently, government agencies, universities, laboratories, and manufacturers have conducted interesting research on large molecule phthalates. These studies show that large phthalates are converted to metabolites within a few minutes of entering the body and broken down.

Over the past 10 years, data provided by the Centers for Disease Control and Prevention indicate that the likelihood of being exposed to phthalate production sources simultaneously is very low. This probability is much lower than the level set by scientists in regulatory agencies; So it can be said that this is not harmful to the body.

The European Chemicals Representative published a study in 2013 on the potential dangers of public use of DINP, DIDP, and DOP. In these studies, they concluded that the safe and healthy use of DINP, DOP, and DIDP is not a threat to children and adults. The use of shoes, gloves, curtains, artificial leather in the interior of cars and homes, children’s school supplies such as bags, pencils, and school erasers, wires and cables, and wall and floor coverings do not pose a health threat.

Our technicians have professional experience in the production and sale of DOP. Our knowledge has led us to use this substance for domestic consumption and export abroad. We also use our knowledge to gain expertise in project monitoring, to help set up and optimize catalyst performance.

If you want more information about buying DOP or the purchase price of Dioctyl Phthalate (DOP), you can contact us and our specialists.


Is the production of Dioctyl phthalate banned in global industries?

Yes! Because this substance contains dangerous chemicals. Some types of Dioctyl phthalate are not produced; Production of DEHP, DBP and BBP is banned in global industries

What are the uses of Dioctyl phthalate worldwide?

DOP is used to produce building insulation, building flooring, durable plastics, adhesives, and films.

Is Dioctyl phthalate harmful to human health?

Yes! DOP contains hazardous substances; For example, H360 can harm fetuses and babies. In addition, H410 harms aquatic animals. This substance can also harm human and animal health.

What are the ways Dioctyl phthalate enters the body?

As we know, Dioctyl phthalate is used in various industries. This substance can enter the body in different ways. For example, eating, injecting, and absorbing skin.

How to get rid of DOP?

Dioctyl phthalate products should be eliminated from life. For example, do not use drugs, cosmetics, toys, and processed meats and foods!

How do we know if the products we use contain Dioctyl phthalate?

It is difficult to detect the presence of Dioctyl phthalate in a substance! The only way is to check the standard and safety labels of the products to see if they contain phthalates.

Do we have to worry about using DOP-containing materials?

We know that phthalates contain chemicals. If these chemicals enter the body, it can cause severe damage to human health.

What are the disadvantages of inhaling substances with DOP?

Try not to be in phthalate environments! Because by inhalation in environments containing phthalates, this substance enters the body. This causes damage to the lungs, lungs and cells.

Is DOP harmful to human hair?

We know that DOP is used to make cosmetics and perfumes. Various experiments have shown that the entry of DOP into the body increases hair loss and decreases sex hormones.