Testing methods for plastic films cover various aspects, including mechanical, optical, and barrier properties. Mechanical property testing encompasses indicators such as tensile strength, elongation, tear performance, coefficient of friction, heat seal strength, peel force, and impact resistance. Relevant national standards include GB/T 1040-1992 (Test methods for tensile properties of plastics), GB/T 13022-1991 (Test methods for tensile properties of plastic films), GB/T 16578-1996 (Test methods for tear resistance of plastic films and sheeting-trouser tear method), QB/T 1130-1991 (Test methods for right-angle tear properties of plastics), GB/T 11999-1989 (Test methods for tear resistance of plastic films and sheeting-Elmendorf method), GB/T 10006-1988 (Determination of coefficient of friction for plastic films and sheeting), QB/T 2358-1998 (Test methods for heat seal strength of plastic film packaging bags), GB/T 8808-1988 (Test methods for peel strength of flexible composite plastic materials), GB/T 8809-1988 (Test methods for pendulum impact resistance of plastic films), and GB/T 9639-1988 (Test methods for impact resistance of plastic films and sheeting-free-falling dart method).
Optical property testing, such as for light transmission and haze, follows standards like GB/T 2410-2008 (Determination of the luminous transmittance and haze of transparent plastics).
Barrier property testing, such as for water vapor permeability, can be performed using methods involving electric testers or cup testers.
Comprehensive film testing services also include dimensional testing (e.g., shrinkage), seal strength, package integrity, and the evaluation of optical properties (gloss, haze, and clarity).