Diisononyl Phthalate (DINP) Plasticizer

What Is Diisononyl Phthalate?

Diisononyl Phthalate, commonly known as DINP, is a high-molecular-weight phthalate plasticizer primarily used to improve the flexibility, processability and durability of PVC.

DINP is generally supplied as a clear, nearly colorless, oily liquid with low water solubility and relatively low volatility. Commercial DINP is a mixture of branched C9 phthalate ester isomers rather than a single pure molecular structure.

DINP Identification and Typical Properties

These are general reference properties. The confirmed specification and lot-specific Certificate of Analysis take precedence.

Why Does DINP Have Two CAS Numbers?

DINP is a commercial mixture of isomeric esters produced from phthalic anhydride and isononyl alcohol streams. Different manufacturing routes and alcohol compositions may be represented by CAS No. 28553-12-0 or CAS No. 68515-48-0.

Buyers should include the required CAS number, regulatory status and intended application in the purchase specification. Products sold under the general name DINP should not automatically be assumed to have identical composition or approvals.

What Does DINP Do in Flexible PVC?

DINP reduces intermolecular forces between PVC polymer chains, allowing the finished compound to remain flexible. It can provide:

• Good compatibility with PVC

• Relatively low volatility

• Flexible processing behavior

• Resistance to migration and extraction in suitable formulations

• Low-temperature flexibility

• Long-term performance in durable PVC applications

• A practical balance between performance and formulation cost

Final performance depends on PVC resin, plasticizer loading, stabilizers, fillers and processing conditions.

Where Is DINP Used?

DINP is primarily used in durable flexible-PVC formulations where flexibility, processing performance and reduced volatility are important.

Wire and Cable Compounds

DINP is used in selected electrical cable insulation and jacketing compounds. Electrical-grade applications may require additional testing for volume resistivity, moisture and impurity control.

Flooring and Wall Coverings

It can be incorporated into flexible vinyl flooring, carpet backing and wall coverings to improve flexibility and processing.

Coated Fabrics and Synthetic Leather

DINP is used in PVC-coated fabrics, upholstery materials and selected synthetic-leather formulations.

Hoses, Profiles and Flexible PVC Products

Applications may include flexible profiles, hoses, membranes and other durable PVC products. Suitability must be confirmed for the final operating conditions.

Sealants, Mastics and Plastisols

DINP may be used in sealants, mastics and PVC plastisols where viscosity, permanence and flexibility are required.

Which DINP Grade Should You Choose?

General-Purpose PVC Grade

Designed for flooring, coated fabrics, profiles, sealants and other conventional flexible-PVC applications.

Electrical Grade

Electrical cable formulations may require tighter limits for water, acidity, conductivity-related impurities and volume resistivity.

Low-Color or Application-Controlled Grade

Clear, pale or appearance-sensitive products may require lower color values and tighter controls over heat stability and residual impurities.

A general industrial grade should not be used in regulated applications without confirming the required compliance documentation.

Which DINP Specifications Should Buyers Compare?

Specifications should be agreed before purchase. A single purity value is not sufficient to qualify DINP for every PVC application.

DINP Regulatory and Application Restrictions

DINP is subject to application-specific restrictions in several markets. Its use is restricted in certain toys, childcare articles and other regulated products.

Before selecting DINP, buyers should confirm:

• Destination-country chemical regulations

• REACH and other substance restrictions

• Children’s-product requirements

• Customer restricted-substance lists

• Electrical, automotive or construction standards

• Required testing and declarations

Regulations change over time. Compliance should be evaluated for the finished article, not only for the raw material.

Packaging, Storage and Handling

Store DINP in tightly closed, compatible containers in a cool, dry and well-ventilated area. Protect it from contamination, moisture, excessive heat and strong oxidizing materials.

Drums, IBCs and bulk packaging may be available depending on order volume and destination. Packaging, shelf life and transport requirements should be confirmed in the quotation and current Safety Data Sheet.

Which Documents Should a Supplier Provide?

Depending on the application, buyers may request:

• Lot-specific Certificate of Analysis

• Safety Data Sheet

• Technical Data Sheet

• Approved product specification

• Country-of-origin information

• REACH or chemical-inventory status

• RoHS, SVHC or customer-specific declarations when applicable

• Packaging and transport information

• Sample testing before commercial approval

Document availability should be confirmed before relying on any compliance claim.

Why Source DINP from AOZUN?

AOZUN can help customers review DINP requirements for PVC cables, flooring, coated fabrics, plastisols, sealants and other industrial formulations.

For an accurate quotation, provide:

• Intended application

• Required CAS number

• Quality specification

• Annual or order quantity

• Preferred packaging

• Destination country

• Required regulatory documents

Product origin, specification, packaging and document availability remain subject to the confirmed quotation.

Frequently Asked Questions

Is DINP organic or inorganic?

DINP is an organic phthalate ester.

Is DINP a fine chemical or a chemical intermediate?

DINP is primarily a high-volume specialty plasticizer. It is not normally classified as a reaction intermediate. If only “fine chemical” or “intermediate” is available, specialty or fine chemical is the closer category.

Is DINP a single pure compound?

Commercial DINP is generally a mixture of branched C9 phthalate ester isomers. This is why different DINP products may use different CAS numbers.

What is the difference between DINP and DOP?

DINP has a higher molecular weight and generally lower volatility than DOP or DEHP. It is often selected for durable flexible-PVC applications, but it should not be treated as an automatic drop-in replacement without formulation testing.

Can DINP be used in children’s products?

DINP is restricted in certain toys and childcare articles in markets including the United States and European Union. Buyers must verify current requirements for the destination market and finished article.

Is DINP suitable for electrical cables?

DINP is used in selected cable compounds. Electrical applications may require specific volume-resistivity, moisture, volatility and aging-performance limits.

Request a DINP Quote

Contact AOZUN with your required CAS number, specification, application, quantity, packaging and destination. Our team will review the requirements and provide the appropriate product information and quotation.