Stretch film, also known as stretch film, is a new type of industrial packaging film products. It is characterized by light, soft and thin, good tensile properties, elongation properties and self-adhesive properties. Its application in transportation packaging is a packaging method that improves packaging efficiency and saves costs. In order to ensure the production quality of packaging stretch film, manufacturers need to produce according to certain standards. This article introduces the test methods for the performance of stretch stretch films based on the packaging industry standard of the People’s Republic of China “BB/T 0024-2018 Stretch stretch films for transport packaging”.
1.Thickness
Carry out in accordance with the provisions of GB/T 6672. Cut the entire sample of 100mm along the length direction, measure 20 points after standing for 30min, the reading is accurate to 0.001mm, and take the arithmetic mean value.
2.Tensile force and elongation at break
In accordance with the provisions of GB/T 1040.3, type II samples are used, with a width of 15mm. The test sample should be cut after unwinding 1m, and cut evenly at approximately equal intervals along the length or width of the sample. During the test, the TST-01 clamp distance of Theo electromechanical tensile testing machine is 50mm, the gauge length is 50mm, and the test speed is 250mm/min±25mm/min. There are two sets of vertical and horizontal sets, each set of samples shall not be less than 5, and the arithmetic mean value shall be taken, accurate to 0.1N.
3.Stickiness
According to Appendix A of “BB/T 0024-2018 Stretch Wrap Film for Transport Packaging”. Sampling begins after the test sample is unrolled 1m, and the samples are divided into two groups of 500mm×125mm (vertical×horizontal) and 180mm×25mm (vertical×horizontal). After the sample is successfully clamped according to the method specified in the standard, pull the clamp at a speed of 125mm/min±12.5mm/min until the two samples are separated, record the maximum force value during the separation process, and the reading is accurate to 0.1N.
4.Anti-puncture
According to Appendix C of “BB/T 0024-2018 Stretch Wrap Film for Transport Packaging”. Fix the sample in the fixture of the experimental device specified in the standard. Start the instrument and test the puncture needle at a speed of 250mm/min±12.5mm/min, and the experiment will stop when the puncture needle passes through the film completely. If the film is broken at other positions, the sample shall be discarded. Record the rupture force (N) and elongation (mm) of the sample when it ruptures.
