GB/T 1845.2 - 2021 Focused polyethylene (PE) (PE) molding and extrusion materials. This part mainly specifies sample preparation and performance measurement. In terms of sample preparation, detail the various links from raw material selection to molding, such as injection molding and extrusion molding conditions, to ensure that the sample is representative. The performance measurement covers mechanical properties such as tensile, Impact, bending, as well as physical properties such as density and melt mass flow rate, and clarifies the test methods, equipment requirements and operation procedures. Through this standard, the performance data of PE materials can be accurately obtained, providing a key basis for its quality control, product design and application.