PLASTIC FILM TESTING EQUIPMENT

Understanding how a plastic film seals, slides, withstands handling, and resists gas transmission helps you select materials suited to their intended application. RDM Test Equipment supplies plastic film testing equipment for heat seal and hot tack strength, coefficient of friction, tear and impact resistance, gas permeation, and optical properties. Explore the instruments below to support material development, investigate performance differences, and establish repeatable quality-control checks.

FAQs ABOUT PLASTIC TESTING EQUIPMENT

Which tests do I need to evaluate a plastic packaging film?

Choose tests according to what the film needs to do and the problems you need to investigate. Heat seal and hot tack testing assess sealing behaviour; coefficient of friction testing evaluates slip; tear and impact tests investigate different types of mechanical resistance; and permeation tests measure gas or water vapour transmission. Optical measurements address appearance and light transmission.

Start with the intended application, relevant specifications, and production requirements. There is no single test that establishes overall film suitability. Build a test plan around the properties that matter, using consistent specimen preparation and documented test conditions.

What is the difference between heat seal strength and hot tack testing?

Heat seal strength testing assesses a seal after it has cooled for a defined period. Hot tack testing measures seal strength immediately after sealing, while the seal is still tacky. The distinction matters where a newly formed seal is loaded before it has fully cooled, such as during filling.

A strong cooled seal does not, by itself, establish adequate hot tack performance. Control sealing temperature, pressure, and dwell time, as well as the delay before testing and the test procedure. The measurements answer different questions and may both be needed when establishing suitable sealing conditions.

How can coefficient of friction testing help investigate film-feeding problems?

Coefficient of friction (CoF) testing measures resistance to sliding between surfaces. Static CoF relates to starting movement, whereas kinetic CoF relates to continued sliding. Depending on the application, testing may compare film against film or film against a representative machine-contact surface. The results can help investigate differences between batches, printed or coated surfaces, and material combinations. Keep the contacting surfaces and test conditions consistent. Use CoF data alongside production observations: feeding problems can also involve machine settings, tension, alignment, and other variables, so friction should not be treated as the sole explanation.

What is the difference between tear resistance and impact resistance testing?

Tear testing assesses how a tear develops under a defined procedure. For example, Elmendorf testing measures resistance to continuing a tear from an initial cut. Impact testing assesses the film’s response to a sudden load, such as a falling dart. These measurements are not interchangeable. Select the test that represents the property you need to evaluate, and record the method, specimen thickness, and orientation where relevant. A favourable result in one test does not establish performance in the other or guarantee resistance to every form of handling damage.

How do I choose between OTR, WVTR and CO2TR testing for plastic films?

Oxygen Transmission Rate (OTR) measures oxygen transmission, Water Vapour Transmission Rate (WVTR) measures water vapour transmission, and Carbon Dioxide Transmission Rate (CO2TR) measures carbon dioxide transmission. Select the measurement according to which gas or vapour needs to be controlled in your application; some films require more than one barrier assessment. Compare results obtained under compatible temperature, humidity, and gas concentration or pressure conditions, using the same reporting basis. One transmission rate should not be used as a substitute for another. Barrier data supports material selection but does not independently establish product shelf life.

What do haze, light transmittance, and clarity measurements tell me about a film?

Light transmittance describes how much light passes through a specimen. Haze describes light scattering associated with a cloudy appearance, while clarity concerns how distinctly objects can be seen through the material. These measurements describe different optical characteristics – choose the measurement that matches your appearance specification rather than relying on a general description such as “transparent”. Keep specimen preparation, cleanliness, and test conditions consistent, and check the instrument’s documented measurement capabilities and applicable methods before comparing results from different systems.

Should I test the film itself or the finished package?

Test the film when you need to characterise the material, compare structures, or check incoming batches. Test the finished package when the question concerns the assembled pack, including its seals, closures, and manufacturing effects. Both levels may be relevant to a packaging evaluation.

What information should I provide when choosing plastic film testing equipment?

Provide the film structure, thickness, intended application, and property you need to measure. Include any required test standard or customer specification, expected measurement range, specimen format, and daily testing volume. For multilayer films, describe the complete construction rather than only the outer surface. Also explain the production problem or development decision the results need to support. When discussing your requirements with RDM Test Equipment, include any necessary environmental controls, data-recording needs, or existing equipment. This gives a clearer basis for checking instrument suitability, fixtures, and sample-preparation requirements.