Flexible packaging in food packaging occupies an important position, with the increasing emphasis on food safety in China, the food terminal business requirements for packaging quality is getting higher and higher, making the flexible packaging companies have to be flexible packaging system before its comprehensive testing, To ensure the yield, maintaining corporate reputation. But most of the domestic flexible packaging enterprises only fit the end customer care project for testing, which is not conducive to the expansion of new customers. I engaged in the packaging of plastic film, bag quality inspection work, is combined with GB / T 10004-2008 "packaging plastic composite film, bag dry compound, extrusion composite", from the test note to the key test project control, To provide a reference for flexible packaging enterprises to understand product performance and master product quality.
Before the detection of samples, to do some preparatory work, the more important of which is the adjustment of the state of the sample and the test standard environment settings. The purpose of the sample conditioning is to ensure that all the tested film samples are in a constant temperature and humidity environment to exclude the impact of environmental factors on the measured data to obtain reproducible and comparable test results. Environmental temperature and humidity and film samples placed in a constant environment, the length of time the performance of flexible packaging products have a greater impact on test results. For example, the rise in ambient temperature tends to cause certain mechanical properties of plastics, especially thermoplastics, such as tensile strength, modulus of elasticity, yield stress and hardness.
The standard environment of the test is equivalent to the average environmental conditions of the laboratory. The plastic film is composed of many polymer chains with repeating link. After the cooling, the macromolecule chain is temporarily frozen. It takes time for the molecular chain to stretch sufficiently. The speed of stretch is closely related to the ambient temperature and humidity. Therefore, the test should be the standard environment of the sample state of the adjustment, and in this state under the test, so that the test results are comparable. The condition of the test specimen and the test standard environment are adjusted and set according to the standard environment and the normal deviation range stipulated in GB / T 2918-1998 Standard Environment for Adjusting and Testing the Plastic Specimen, ie the temperature is (23 ± 2) The relative humidity is (50 ± 10)%. It should be noted that the adjustment time can not be less than 4h.
Sampling should be in accordance with the relevant technical standards and norms, from the test object extraction of experimental samples. Sampling involves the acquisition of the test object (sampling) and the preparation of the test sample (preparation).
Sampling requires that the samples be representative and homogeneous. Estimating and deducing the characteristics of all samples through the detection of the samples is a cost-effective method commonly used in scientific experiments, quality tests, and social surveys.
Sample preparation refers to the purpose of the test, the sample processed into a test for the operation of the unified characteristics of a standardized sample. The resulting samples must also be representative in order to truly reflect some of the characteristics of the material being analyzed.
Sampling is the first condition to ensure correct detection, sampling representative and uniformity of the reaction batch product quality conditions, standardization of sample preparation to ensure reproducibility of the test results and the comparison between the test data comparability. It is noteworthy that the sample taken during the sampling process should be intact, the number of samples must be sufficient to complete all the pilot projects.