Plastic films are widely used in packaging and industrial applications where material performance depends on mechanical properties, structure and the ability to limit the transmission of gases and water vapor.
Permeability testing of plastic films helps laboratories characterize these barrier properties, compare materials and evaluate their performance under defined test conditions.
ExtraSolution provides instruments for measuring oxygen transmission rate (OTR), water vapor transmission rate (WVTR) and carbon dioxide transmission rate (CO₂TR) through films and barrier materials.
Why Measure the Permeability of Plastic Films?
The barrier performance of a plastic film depends on its composition, thickness, structure and the conditions under which it is tested.
Measuring permeability helps laboratories and manufacturers:
- Characterize the barrier properties of plastic films.
- Compare different materials and film formulations.
- Evaluate multilayer and coated film structures.
- Support research and development activities.
- Qualify materials for specific applications.
- Perform quality control and monitor material consistency.
- Permeability measurements provide quantitative data that can be used alongside other material properties when selecting or developing films.
Which Permeability Parameters Can Be Measured?
The appropriate parameter depends on the substance whose transmission needs to be evaluated.
Oxygen Transmission Rate (OTR)
OTR measures the amount of oxygen passing through a film under specified test conditions. It is commonly used to characterize oxygen barrier performance and compare materials intended to limit oxygen transmission.
Explore Oxygen Permeability and OTR: Measurement and Analysis.
Water Vapor Transmission Rate (WVTR)
WVTR measures the amount of water vapor passing through a film under specified test conditions. It helps characterize the film’s moisture barrier performance.
Explore Water Vapor Permeability and WVTR: Measurement and Analysis.
Carbon Dioxide Transmission Rate (CO₂TR)
CO₂TR measures the amount of carbon dioxide passing through a film under specified test conditions. It is useful when carbon dioxide transmission is relevant to the material’s intended application.
Explore CO₂ Permeability and CO₂TR: Measurement and Analysis.
Which Plastic Films Can Be Tested?
Depending on the instrument configuration and applicable test method, permeability testing can be used to characterize different types of films and film-based structures, including:
- Plastic packaging films
- Barrier films
- Multilayer films
- Laminated structures
- Metallized films
- Co-extruded films
The suitability of a specific material depends on its characteristics, the parameter being measured and the available test configuration.
Factors That Influence Film Permeability
Several factors can affect the transmission of gases and water vapor through a plastic film.
Material Composition
The polymer type and material formulation influence the interaction between the film and the substance passing through it. Different materials can therefore exhibit different barrier performance.
Film Thickness
Thickness is an important factor when characterizing and comparing films. Results should be interpreted in relation to the measurement method and the way transmission values are reported.
Film Structure
Coatings, metallized layers and multilayer constructions can affect the overall barrier performance of a film. Evaluating the complete structure helps characterize the material as it will be used.
Temperature and Relative Humidity
Test temperature can affect transmission behavior. Relative humidity is particularly important for water vapor measurements and may also be relevant to other test conditions.
Test Method and Conditions
Meaningful comparisons require clearly defined test conditions and appropriate methods. When comparing results, laboratories should consider the measurement parameter, units, test conditions and applicable standards.
Permeability Testing of Multilayer Plastic Films
Many plastic films are designed as multilayer structures to combine different material properties, including barrier performance, mechanical strength and sealing characteristics.
Testing these structures helps laboratories compare alternative constructions and assess their performance against specific gases or water vapor.
For more information, explore Permeability Testing of Multilayer Films and Laminates.
How Is Plastic Film Permeability Measured?
Permeability testing measures the transmission of a specific gas or water vapor through a film under defined conditions.
The procedure depends on the parameter being evaluated, the sample and the selected test method. Temperature, relative humidity, material structure and test configuration should be considered when planning measurements and interpreting results.
For laboratories comparing different films, using consistent test conditions helps ensure that the resulting data can be interpreted meaningfully.
How to Choose a Plastic Film Permeability Tester
When selecting a permeability tester, consider the following factors:
- Measurement requirements: determine whether OTR, WVTR, CO₂TR or a combination of parameters is needed.
- Sample characteristics: consider film type, structure and thickness.
- Test conditions: identify the required temperature and humidity conditions.
- Laboratory workflow: determine the number of samples and measurements required.
- Applicable methods: verify the test method and measurement range needed for the application.
- Data management: consider the laboratory’s requirements for recording, reviewing and comparing results.
- The most suitable solution depends on the films being tested and the objectives of the laboratory.
ExtraSolution Instruments for Plastic Film Permeability Testing
ExtraSolution offers several solutions for characterizing the barrier properties of plastic films.
MultiPerm O2-CO2
Measures oxygen transmission rate (OTR) and carbon dioxide transmission rate (CO₂TR).
Explore MultiPerm O2-CO2.
MultiPerm O2-H2O
Measures oxygen transmission rate (OTR) and water vapor transmission rate (WVTR).
Explore MultiPerm O2-H2O.
MultiPerm H2O-CO2
Measures water vapor transmission rate (WVTR) and carbon dioxide transmission rate (CO₂TR).
Explore MultiPerm H2O-CO2.
TotalPerm
Combines OTR, CO₂TR and WVTR measurement capabilities in one integrated system.
Explore TotalPerm.
PermeH2O
Provides a dedicated solution for measuring water vapor transmission rate (WVTR).
Explore [PermeH2O].
Characterize Plastic Film Barrier Properties with ExtraSolution
Permeability testing provides important data for material development, film comparison and quality control. By measuring OTR, WVTR and CO₂TR under defined conditions, laboratories can better characterize the barrier performance of plastic films and multilayer structures.
Contact ExtraSolution to discuss your materials and identify a suitable permeability testing solution for your application.