Multilayer films and laminated materials are widely used in packaging applications where different material layers are combined to achieve specific performance requirements. These structures can provide a combination of barrier, mechanical, sealing and processing properties.
Permeability testing of multilayer films and laminates helps laboratories characterize the barrier performance of the complete structure and compare materials 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 Multilayer Films?
The barrier performance of a multilayer film depends on the materials used, their arrangement and the characteristics of the complete structure.
Permeability measurements help manufacturers and laboratories:
- Characterize the barrier properties of multilayer films and laminates.
- Compare different material combinations and structures.
- Evaluate alternative packaging material designs.
- Support research and development activities.
- Qualify materials for specific applications.
- Monitor material performance during quality control.
Testing the complete structure provides information about its overall transmission performance under the selected test conditions.
Which Permeability Parameters Are Important?
The relevant parameter depends on the substance that needs to be evaluated and the intended application of the material.
Oxygen Transmission Rate (OTR)
OTR measures the amount of oxygen passing through a multilayer film or laminate under specified test conditions. It helps characterize the oxygen barrier performance of the complete structure.
Learn more about Oxygen Permeability and OTR: Measurement and Analysis.
Water Vapor Transmission Rate (WVTR)
WVTR measures the amount of water vapor passing through a multilayer film or laminate under specified test conditions. It helps evaluate the moisture barrier performance of the structure.
Learn more about Water Vapor Permeability and WVTR: Measurement and Analysis.
Carbon Dioxide Transmission Rate (CO₂TR)
CO₂TR measures the amount of carbon dioxide passing through a material under specified test conditions. It is relevant when carbon dioxide transmission is an important consideration for the intended packaging application.
Learn more about CO₂ Permeability and CO₂TR: Measurement and Analysis.
Which Multilayer Materials Can Be Tested?
Depending on the instrument configuration and applicable test method, permeability testing can be used to characterize a range of multilayer materials, including:
- Laminated films
- Multilayer plastic films
- Co-extruded films
- Metallized films
- Flexible packaging laminates
- Other film-based barrier structures
The suitability of each sample depends on its construction, characteristics and the test configuration available.
How Does Multilayer Structure Affect Barrier Performance?
Multilayer structures combine different materials to achieve specific performance requirements. Each layer contributes to the properties of the complete film, and the overall barrier performance depends on the materials and how they are assembled.
Factors to consider include:
Material Selection
Different polymers and other materials can exhibit different gas and water vapor transmission characteristics. The choice of each layer influences the performance of the final structure.
Layer Arrangement
The sequence and arrangement of the layers can affect the behavior of the complete structure. Evaluating the finished laminate helps determine its overall barrier performance.
Metallization and Coatings
Metallized layers and coatings may be used to modify barrier performance. Measurements help characterize the resulting structure under defined test conditions.
Thickness and Overall Construction
The thickness and composition of the complete structure are important when comparing different materials. Results should be interpreted in relation to the sample characteristics and measurement method.
Temperature and Relative Humidity
Test conditions can influence transmission measurements. Temperature and relative humidity should be selected and documented according to the material and the applicable test method.
Permeability Testing of Laminates
Laminates combine two or more material layers to achieve a specific combination of properties. In packaging, these may include barrier performance, mechanical resistance and sealing characteristics.
Measuring OTR, WVTR or CO₂TR helps characterize the finished laminate rather than relying only on the properties of its individual components.
This information can support:
- Comparison of alternative laminate constructions.
- Evaluation of material changes during development.
- Characterization of barrier performance.
- Material qualification.
- Quality control and consistency checks.
How Is Multilayer Film Permeability Measured?
Permeability testing involves measuring the transmission of a selected gas or water vapor through a sample under defined conditions.
The measurement approach depends on the parameter being evaluated, the characteristics of the multilayer structure and the selected test method.
When planning a test, laboratories should consider:
- The transmission parameter required: OTR, WVTR or CO₂TR.
- The material composition and structure.
- Sample preparation and mounting requirements.
- Temperature and relative humidity conditions.
- The applicable test method and measurement range.
- How results will be compared and documented.
Consistent test conditions are essential when comparing alternative laminates or monitoring changes in material construction.
How to Choose a Permeability Tester for Multilayer Films
The appropriate instrument depends on the types of materials and transmission parameters to be evaluated.
When selecting a system, consider:
- Measurement parameters: determine whether oxygen, water vapor, carbon dioxide or multiple substances need to be measured.
- Material types: verify compatibility with the multilayer films and laminates being tested.
- Test conditions: identify the required temperature and humidity conditions.
- Testing workflow: consider sample throughput and whether one or more parameters must be evaluated.
- Measurement range and methods: verify that the instrument meets the requirements of the intended tests.
- Data management: consider the laboratory’s needs for recording and comparing results.
A system capable of measuring multiple transmission parameters can be useful when the same material needs to be characterized for different barrier properties.
ExtraSolution Instruments for Multilayer Film and Laminate Testing
ExtraSolution offers solutions for characterizing multilayer films, laminates and other barrier materials.
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 Multilayer Films and Laminates with ExtraSolution
Permeability testing helps laboratories evaluate the overall barrier performance of multilayer films and laminates, compare alternative structures and support material development and qualification.
ExtraSolution provides solutions for measuring oxygen, water vapor and carbon dioxide transmission through films and barrier materials.
Contact ExtraSolution to discuss your multilayer film or laminate application and identify a suitable permeability testing solution.