Understanding EVA Resin Density and How to Compare Different Grades

EVA resin density is an important physical property when manufacturers evaluate raw materials for film production, compounding, and footwear applications. However, different commercial grades do not share one universal density value. Their specifications vary with vinyl acetate (VA) content, polymer characteristics, and grade design.

For material buyers and processors, understanding density EVA values helps with grade comparison, material calculations, and incoming quality checks. It also helps prevent a common mistake: treating the density of unfoamed EVA resin as equivalent to the density of a formulated compound or finished EVA foam.

This guide explains what determines EVA copolymer density, compares three commercial grades using manufacturer data, and outlines the main methods used to measure it.

What Is EVA Resin Density?

EVA, or ethylene-vinyl acetate, is a copolymer made from ethylene and vinyl acetate. Manufacturers produce different EVA resins with varying VA content and other grade characteristics to meet specific processing and application requirements.

Density describes the mass of a material per unit of volume. For EVA resin, manufacturers commonly report it in:

• g/cm³: grams per cubic centimeter
• kg/m³: kilograms per cubic meter

The conversion is straightforward:

1 g/cm³ = 1,000 kg/m³

For example, an EVA resin with a density of 0.930 g/cm³ has an equivalent density of 930 kg/m³.

Density is a physical property, not a direct measurement of hardness, flexibility, or melt flow. Two EVA grades may have similar densities but different melt indexes and VA contents. Therefore, density alone cannot establish whether a resin is suitable for a particular manufacturing process.

For a broader introduction to the material and its production, see the EVA material manufacturing process.

What Is the Typical Density of EVA Resin?

There is no single density value that applies to all EVA resins. Commercial grades have different specifications, and manufacturers select their material compositions and processing characteristics for particular applications.

Manufacturer technical data sheets provide a more useful reference than a general density estimate. The following examples illustrate the differences between three commercial grades.

Commercial EVA Resin Density Examples

The values above are manufacturer-reported typical properties, not guaranteed specifications. Melt index values should also be compared using their stated test conditions. The Hanwha grades report melt index at 190°C and 2.16 kg.

The examples show that density varies across commercial EVA grades. Ateva 2820AG has a reported density of 0.948 g/cm³, while Hanwha EVA 2240 and 2030 have reported values of 0.929 and 0.927 g/cm³, respectively.

Their applications also differ. Celanese identifies Ateva 2820AG for medical applications, while Hanwha identifies EVA 2240 for flexible packaging and EVA 2030 for blown film. These products are examples for understanding material specifications, not interchangeable recommendations for footwear production.

A useful EVA density chart should therefore identify the exact manufacturer and grade rather than present a single figure as the density of all EVA resins.

Manufacturer references:

• Celanese Ateva 2820AG Technical Data Sheet
• Hanwha EVA 2240 Product Document
• Hanwha EVA 2030 Technical Data Sheet

Factors That Affect EVA Resin Density

Commercial EVA grades differ for several reasons. VA content is one important factor, but it does not explain every density difference.

Vinyl Acetate Content

VA content describes the proportion of vinyl acetate in the EVA copolymer. It influences the polymer’s molecular structure and physical behavior.

As VA content increases, the polymer generally develops lower crystallinity. This change can affect flexibility, softness, transparency, and other properties. It can also influence density.

However, manufacturers should not assume that density follows one simple linear relationship with VA content. The density of a commercial grade also depends on other polymer characteristics and grade-design variables.

The three examples in the comparison table illustrate why buyers should evaluate actual technical data rather than estimate density from VA content alone.

Polymer Structure and Grade Characteristics

EVA manufacturers design grades for different processing methods and end uses. Differences in polymer characteristics can influence density as well as melt flow, thermal behavior, and mechanical performance.

For example, a grade designed for blown film may have different processing requirements from one developed for molding or other applications. Even when two materials share a similar VA content, their complete property profiles may differ.

Consequently, procurement teams should compare the full technical data sheet instead of selecting a resin based on one specification.

Additives and Formulation

It is also important to distinguish neat EVA resin from a formulated EVA compound.

A neat resin refers to the base copolymer. By contrast, a compound may contain EVA resin alongside fillers, pigments, plasticizers, crosslinking agents, foaming agents, and other ingredients.

These additional materials can change the compound’s overall density. For instance, adding a mineral filler may increase density, while other formulation choices can produce different effects.

Therefore, the density of an EVA compound should not automatically be reported as the density of its original resin. Manufacturers evaluating a formulation should consider the EVA compounding process and identify exactly which material the reported value describes.

How Is EVA Resin Density Measured?

Manufacturers and testing laboratories use standardized methods to determine the density of solid plastics. Two relevant standards are ASTM D1505 and ASTM D792.

ASTM D1505: Density-Gradient Technique

ASTM D1505 covers the determination of density for solid plastics using a density-gradient technique.

The method uses a liquid column with a controlled density gradient. A prepared test specimen is placed in the column, and its equilibrium position is compared with reference standards of known density. Its position helps establish the specimen’s density.

This method appears in the technical documentation for Hanwha EVA 2240 and EVA 2030. Celanese also lists ASTM D1505 alongside ASTM D1928 Procedure A for the density property of Ateva 2820AG.

ASTM D792: Displacement Method

ASTM D792-20 describes methods for determining the density and specific gravity of solid plastics by displacement.

The basic principle involves determining the volume of a solid specimen from the liquid it displaces. When the specimen’s mass and displaced volume are known, its density can be calculated.

ASTM D792 includes methods for testing solid plastics in water and in liquids other than water. The appropriate method and test conditions depend on the specimen and the requirements of the test.

What Should Manufacturers Check?

When comparing density data from different suppliers, check the following details:

• Test method: Confirm whether the supplier used ASTM D1505, ASTM D792, or another recognized method.
• Sample preparation: Check whether the specimen represents neat resin or a formulated material.
• Test conditions: Review the conditions specified in the test method and technical documentation.
• Property status: Determine whether the value is typical, a guaranteed specification, or a measured batch result.
• Document version: Use current technical documentation where possible, and confirm that the grade name matches the material being purchased.

Different methods and sample conditions can affect the comparability of reported results. A meaningful comparison requires more than placing two density figures side by side.

Why Does EVA Resin Density Matter in Manufacturing?

Density helps manufacturers understand and compare raw materials before processing. Although it cannot predict every aspect of performance, it supports several practical decisions.

Material identification and grade comparison: Density can help distinguish materials and identify differences between incoming samples. However, manufacturers should use it alongside VA content, melt index, and other properties rather than treating it as a complete identification test.

Material quantity calculations: Density connects material mass with volume. If a manufacturer knows the density and required volume, the approximate material mass can be calculated. Conversely, density helps estimate the volume occupied by a known mass.

Cost estimation: Many raw materials are purchased by weight. Density can help estimate the mass required for a given material volume, supporting preliminary material and cost calculations. Actual purchasing decisions must still account for the supplier’s pricing basis, formulation, and production losses.

Batch consistency: Regular density checks can help identify unexpected differences between material batches. A change may indicate variation in composition, formulation, or other material characteristics. Further testing is necessary to identify the cause.

For footwear manufacturers, density is only one part of material selection. VA content, melt index, foaming behavior, mechanical properties, formulation compatibility, and processing requirements all influence the suitability of a resin.

These considerations also connect directly to the EVA sole manufacturing process, where material characteristics must match the product design and production method.

EVA Resin Density vs. EVA Foam Density

The terms EVA resin density and EVA foam density describe different materials and should never be used interchangeably.

EVA resin density refers to the density of the unfoamed polymer resin. Manufacturers commonly report it in g/cm³ or kg/m³ in resin technical data sheets.

EVA foam density refers to the apparent density of the finished cellular material. It depends on the foam’s cell structure, expansion, formulation, and processing conditions.

Because foaming introduces gas-filled cells into the material, finished EVA foam generally has a much lower apparent density than the original solid resin. However, its actual density depends on the formulation and manufacturing process.

The distinction matters when comparing technical specifications. A resin density value cannot be used as the finished foam density, and a foam density measurement cannot replace the resin specification.

For more information about testing the finished cellular material, read the guide to the EVA foam density test method. Manufacturers can also explore the EVA foam manufacturing process to understand how formulation and processing influence the final foam structure.

Conclusion: Compare EVA Resin Grades Beyond Density

EVA resin density varies across commercial grades, so manufacturers should not rely on one universal figure when evaluating raw materials. Official technical data sheets provide more reliable comparisons by identifying each grade’s density, VA content, melt index, test method, and intended application.

Density is useful for material identification, quantity calculations, cost estimation, and batch consistency checks. Nevertheless, it does not independently determine resin quality or processing suitability. Manufacturers should evaluate it alongside the other properties that influence their production requirements.

For EVA footwear producers, material selection and equipment selection should work together. KING SUN, the footwear machinery brand of ONE-NINE Machinery Co., Ltd., provides EVA footwear production equipment and solutions. Matching equipment to the selected material, product design, and manufacturing process helps manufacturers plan a more suitable production setup.