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中文简体Choosing a DINP plasticizer is rarely a single-factor decision. Even when two batches carry the same CAS number and nominal purity, differences in viscosity, color stability, acid value, and plasticizing efficiency can change how the resin behaves in wire insulation, flooring, or automotive interior parts. This guide is written for technical buyers who need to verify product data, understand regulatory constraints, and compare DINP with realistic alternatives before they place an order.
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What Is DINP Plasticizer?
Diisononyl phthalate (DINP) is a high-molecular-weight phthalate ester made by esterifying phthalic anhydride with isononyl alcohol. It is sold as a mixture of positional isomers, which is why its CAS number 28553-12-0 covers a family of closely related compounds. In PVC compounding, DINP works by inserting itself between polymer chains, reducing chain-to-chain interactions and converting brittle PVC into a flexible material.
DINP is often preferred over lower-molecular-weight phthalates because it has lower volatility and better resistance to water and soap extraction. Typical dosages lie between 30 and 80 phr, depending on the hardness needed in the final film or part.
Diisononyl Phthalate (DINP) Plasticizer for Flexible PVC CompoundsThis general-purpose plasticizer offers low volatility and good resistance to water and soap extraction. It suits applications such as gloves, toys, cables, and school supplies, providing balanced processability and durability.View Product →Main Applications of DINP in Flexible PVC
DINP appears in a wide range of flexible PVC compounds. It offers a practical balance of processability, permanence, and cost, which is why it remains one of the most widely specified plasticizers globally. The most common end uses are:
- Wire and cable insulation: DINP delivers good volume resistivity and low plastisol viscosity, which simplifies insulation coating and helps maintain electrical performance.
- Flooring and wall coverings: Vinyl flooring benefits from DINP's clarity, stain resistance, and dimensional stability.
- Automotive interior components: Door panels, instrument foil, and seals require low-vapor retention; DINP's low volatility helps reduce fogging.
- Coated fabrics: Tarpaulins, upholstery, and protective clothing use DINP for fast fusion and plasticizer permanence through repeated washing or outdoor exposure.
- Flexible film and sheeting: Agricultural film, pond liners, and construction sheeting rely on DINP when long service life under sunlight is expected.
When you switch from another plasticizer, verify the plasticizing efficiency in your exact formulation. A change in viscosity and gelation temperature can be just as important as the final hardness.
Regulatory and Compliance Considerations
The legal position of DINP varies by market, so buyers must check the relevant framework rather than rely on generic labels. Three areas are particularly important for procurement teams.
- US EPA TSCA: In January 2025, the EPA published its final risk evaluation for DINP. The agency's review covered a broad set of uses and established the conditions under which DINP can be handled without significant risk. This gives US importers a clearer basis for due diligence.
- California Proposition 65: DINP is on the Proposition 65 list because it can cause cancer. Products sold in California must carry a warning if they expose users to DINP above the threshold set by the regulation. Even if you do not sell directly into California, your customers may request Prop 65 testing certificates.
- EU REACH and the Toy Safety Directive: DINP is classified as a reproductive toxicant and is restricted in toys and childcare articles that a child could place in the mouth. It is not banned for all uses; industrial cables, flooring, and many automotive components remain lawful and widely made with DINP.
Do not assume that DINP is an unregulated plasticizer. The picture is nuanced, and a responsible supplier will provide a regulatory summary for your target market.
How DINP Compares with Other Plasticizers
Procurement decisions often involve more than one plasticizer candidate. The table below compares DINP with DEHP, DIDP, and DOTP on the characteristics that most often influence material selection.
| Property | DINP | DEHP | DIDP | DOTP |
|---|---|---|---|---|
| Chemical family | Phthalate | Phthalate | Phthalate | Terephthalate |
| Approx. molecular weight (g/mol) | 418 | 391 | 446 | 390 |
| Plasticizing efficiency | Good | Excellent | Good | Good |
| Low-temperature flexibility | Good | Very good | Moderate | Good |
| Volatility | Low | Higher | Lower | Low |
| Regulatory status | Restricted in child products; EPA TSCA evaluation complete in 2025 | Restricted in many consumer products | Restricted similarly to DINP | Not listed under Prop 65; often used as an alternative |
DIDP is the closest phthalate relative and may be chosen when a slightly lower volatility is required. DOTP is the non-orthophthalate alternative that many compounders adopt when customers demand a plasticizer with a simpler environmental profile.
Dioctyl Terephthalate (DOTP) Plasticizer for High-Insulation Cable MaterialsA stable non-orthophthalate plasticizer with excellent electrical properties and good cold, heat, and extraction resistance. It works well in PVC cable compounds and can be blended with DOP to reduce viscosity in plastisols.View Product →Technical Specifications Buyers Should Check
The name "DINP" alone does not define a usable product. A complete technical data sheet will list a set of parameters that affect both processing and final quality. The table below shows the values you should expect for a standard general-purpose grade.
| Parameter | Typical Value | Why It Matters |
|---|---|---|
| Purity | 99.5% min. | Low purity can indicate side products or catalyst residues. |
| Acid value | 0.1 mg KOH/g max. | High acid value consumes stabilizers and may corrode processing equipment. |
| Water content | 0.1% max. | Free water causes haze in plastisol and voids in extruded products. |
| Color | 30 APHA max. | Color affects the appearance of transparent or light-colored PVC. |
| Density at 20°C | ~0.97 g/cm³ | Used for volumetric recipes, loading, and freight calculations. |
| Viscosity at 20°C | 130–160 mPa·s | Influences plastisol handling, pumping, and deaeration. |
| Flash point | > 210°C | Relevant for storage classification and transportation safety. |
When you review a certificate of analysis, check consistency against your reference sample and look at lot-to-lot variation. Insist on test methods (ASTM, ISO, or national standard) that are comparable from one batch to the next.
Sourcing and Supply Chain Considerations
DINP is a bulk chemical, which means logistics and supplier reliability often matter as much as the quoted price. A manufacturer located near a major port can load ISO tanks without long inland freight legs. For example, a producer based only a few kilometres from a deep-water port can cut lead time and reduce the risk of weather-related delays.
Before signing a contract, request a reference sample and run it through your own mixing and processing conditions. Also ask whether the plant has an ISO quality management system and whether it produces its own phthalic anhydride. Vertical integration from plasticizer to upstream raw material gives the seller more control over purity and supply continuity.
For a practical view of DINP in a compounding line, read our article on DINP plasticizer in PVC manufacturing, which covers performance tests and formulation adjustments in more detail.
If you are a regular importer, consider contract terms that cover price adjustment formulas, tank turnaround time, and the supplier's finished-goods inventory. These clauses will prevent surprises when feedstock prices move quickly.
Working with a Plasticizer Manufacturer
Many converters prefer to work directly with a manufacturer instead of through a broker, especially when product quality and after-sales support are critical. A direct supplier can respond faster to complaints, adjust specifications, and combine different plasticizers in one shipment.
Zhejiang Great Chemical Science & Technology Co., Ltd. is an experienced player in this segment. The company operates a plasticizer manufacturing base near Jiaxing Port in China, employs more than 180 people, and describes itself as a plasticizer chain enterprise with more than 15 years of history. Its product portfolio includes DINP, DOP, DOTP, DOA, DPHP, TOTM, and phthalic anhydride, which makes it possible to consolidate orders and reduce logistics cost.
The company also exports to India, Russia, and other overseas markets and reports that it cooperates with large listed companies in China. When you choose a manufacturer, these kinds of references carry weight because they indicate that the production line has been audited by demanding customers.
You can see the complete product range and factory information on the company website.
Selecting the right DINP plasticizer comes down to three actions: confirm your performance requirements, map the regulatory picture for your destination market, and test the actual product under your own processing conditions. Once those steps are complete, DINP remains a dependable, cost-effective plasticizer for a broad range of industrial PVC products.
