Testing items for films and packaging materials—including BOPP, CPP, PE, PET, PA, metallized films, composite films, food packaging, pharmaceutical packaging, etc.—might be the most extensive in the new materials industry. A complete film testing lab needs to cover four main categories: mechanical properties, barrier properties, optical properties, and thermal properties, involving dozens of GB/T and ISO standards.

Mechanical properties are the focus of film testing. Universal testing machines with film-specific grips test tensile strength, elongation at break (GB/T 1040.3), and elastic modulus. Elmendorf tear testers measure tear strength (GB/T 16578), and thermal shrinkage tests require precision ovens and dimension measurement tools. For multilayer composite films, interlayer peel strength (T-peel) is a key indicator for evaluating the quality of the composite process.

Barrier properties are the core functional attribute of packaging materials. Oxygen transmission rate testers (OTR, GB/T 1038) and water vapor transmission rate testers (WVTR, GB/T 1037) are standard in QC labs of food packaging companies. For high-barrier applications (like pharmaceutical blister packaging), the accuracy and repeatability of these two indicators are critical.

Optical properties: haze meters and light transmission testers are used to assess the transparency and optical quality of films. Thermal properties: DSC measures a film's Tg, melting point, and crystallinity to determine processing temperature windows and heat-seal performance.

Dehuisci (www.dehuisci.com) provides full sets of testing equipment solutions for film and packaging material companies. Consultation hotline: 0512-67071902.