ASTM D5594 Standard Test Method for Determination of the Vinyl Acetate Content of Ethylene-Vinyl Acetate (EVA) Copolymers by Fourier Transform Infrared Spectroscopy (FT-IR)

Get Certified ASTM D5594 Testing Services 

ASTM D5594 testing services provide laboratories with the vinyl acetate content of ethylene-vinyl acetate (EVA) copolymers by measuring the content of these materials with FT-IR spectroscopy. The method offers a uniform way of assessing the composition of EVA and can be used for quality control and material verification programs. The laboratories employ appropriate FT-IR instrumentation, specimen preparation procedures, and calibration protocols to perform this test. ASTM D5594 is the current version listed in the plastics standards of ASTM. Manufacturers, suppliers and purchasers who require EVA material specifications to be documented,seek this documentation from a qualified testing laboratory. ASTM laboratory programs also aid laboratory proficiency and quality assurance.

• Analyzes and quantifies the percent of vinyl acetate in EVA copolymers.
• Applies Fourier transform infrared spectroscopy (FTIR).
• Carries out the analysis of EVA by means of pressed films or molded plaques.
• Applies to EVA copolymers with a vinyl acetate content between 0.5 and 55% vinyl acetate.
• Uses internal corrections for sample thickness.
• Provides a uniform method for EVA composition analysis.
• Removes resins that contain talc and have less than 5 % vinyl acetate, because talc interferes with the 1020 cm⁻¹ vinyl acetate band.
• Helps laboratories check the amount of vinyl acetate in EVA samples.

What are the Uses of ASTM D5594 Testing?

ASTM D5594 is a test that assists laboratories in determining the amount of vinyl acetate in EVA copolymers by FT-IR spectroscopy. Manufacturers and engineers use the results for quality-control activities, verifying material composition and comparing EVA materials. This standard-

• Measures the amount of vinyl acetate in EVA copolymers.
• Supports the verification of EVA material specifications.
• Supports comparison of various EVA formulations.
• Assists in quality assurance and batch-to-batch uniformity.
• Assists in distinguishing between different compositions of EVA.
• Helps select materials and develop products.
• Assists in raw material and finished product evaluations of EVA.

Which materials can be tested under ASTM D2565?

ASTM D5594 covers ethylene-vinyl acetate (EVA) copolymers that analysts can make into appropriate test specimens for FT-IR analysis. The method is applicable to EVA materials from about 0.5 to 55 % vinyl acetate.  The material suitable for a pressed film or molded plaque. An analyst should determine the EVA material, range of vinyl acetate concentration, specimen form, and ensure that there are no interfering components that will impact the measurement using FT-IR. Talc in materials may need special consideration since talc can cause interference with the measurement. 

Why is ASTM D5594 Important? 

ASTM D5594 is a standardized FT-IR procedure for determining the amount of vinyl acetate in ethylene-vinyl acetate (EVA) copolymers. EVA properties such as flexibility, crystallinity, polarity, adhesion, and processability can vary with vinyl acetate content. The test results help manufacturers and engineers to confirm the composition of EVA, to compare different material types, and to ensure consistency between production lots. Manufacturers and engineers also use these results as a quantitative measurement of the vinyl acetate content of the tested EVA copolymer to aid in material selection and quality control and for product development. 

ASTM D5594 Testing Process and Data Collection 

Technicians press an EVA specimen into a film or mold it into a plaque for use in the FT-IR spectrometer. This instrument obtains the infrared spectrum of the specimen within the set range. Technicians find and measure the specific absorption bands for vinyl acetate and ethylene. They consider specimen thickness and use the correct calibration relationship to the measured infrared response. The lab then determines the amount of vinyl acetate in the EVA copolymer. Analysts record the FT-IR measurements, the calculated value, the specimen identification, and the test conditions. The final product is expressed as % vinyl acetate (by weight).

Common Challenges and Troubleshooting

When technicians use a nonrepresentative specimen, improper specimen preparation, or inadequate calibration, ASTM D5594 testing may yield false results. Different specimen thickness or different measurement conditions may also affect the infrared response. Consistently handle samples and use an appropriate calibration, and keep the FT-IR instrument in good condition. Any significant variance of repeated measurements indicates that the laboratory must verify the validity of the specimen preparation, instrument performance, calibration, or measurement setup prior to reporting the final measurement.   

• The laboratory reports the amount of vinyl acetate as a percent by mass, based on the specimen’s infrared absorbance spectrum.
• The analyst determines the appropriate absorption ratio using the characteristic infrared absorption bands of vinyl acetate and ethylene.
• Analysts apply the calibration equation to convert the infrared absorption ratio to the specimen content, which is the amount of vinyl acetate.
• The report compares the measured amount of vinyl acetate with the expected or specified amount (if applicable), enabling the laboratory to determine the composition and consistency of the EVA copolymer.
•  The laboratory reports results within the calibration curve range and does not extrapolate beyond it.

Link to ASTM D5594