The testing of flexible packaging should not be ignored either


Release time:

2021-09-30

Flexible packaging occupies an important position in food packaging. As the Chinese government pays more and more attention to food safety, food terminal companies have higher and higher requirements for packaging quality, which makes flexible packaging companies have to treat them before they leave the factory. Carry out systematic and comprehensive testing to ensure the yield rate and maintain corporate reputation. However, most domestic flexible packaging companies only perform inspections on items that end customers care about, which is very unfavorable for the expansion of new customers. The author has been engaged in the quality inspection of packaging plastic films and bags for many years. Now, in conjunction with GB/T 10004-2008 "Plastic Composite Films and Bags for Packaging Dry Compounding, Extrusion Compounding", from the test precautions to the control of key inspection items, Make a systematic analysis to provide references for flexible packaging companies to understand product performance and master product quality.

[News from China Packaging Network] Flexible packaging occupies an important position in food packaging. As the Chinese government pays more and more attention to food safety, food terminal companies have higher and higher requirements for packaging quality, which makes flexible packaging companies have to treat them before they leave the factory. Carry out systematic and comprehensive testing to ensure the yield rate and maintain corporate reputation. However, most domestic flexible packaging companies only perform inspections on items that end customers care about, which is very unfavorable for the expansion of new customers. The author has been engaged in the quality inspection of packaging plastic films and bags for many years. Now, in conjunction with GB/T 10004-2008 "Plastic Composite Films and Bags for Packaging Dry Compounding, Extrusion Compounding", from the test precautions to the control of key inspection items, Make a systematic analysis to provide references for flexible packaging companies to understand product performance and master product quality.

Test notes

Preparation conditions

Before testing the sample, some preparatory work must be done. The two important ones are the adjustment of the sample state and the setting of the test standard environment. The purpose of sample state adjustment is to ensure that all tested film samples are in a constant temperature and humidity environment to eliminate the influence of environmental factors on the measurement data and obtain reproducible and comparable test results. The environmental temperature and humidity and the length of time the film sample is placed in a constant environment have a greater impact on the performance test results of flexible packaging products. For example, when the ambient temperature rises, certain mechanical properties of plastics, especially thermoplastics, such as tensile strength, elastic modulus, yield stress, and hardness, often decrease.

The standard environment of the test is equivalent to the average environmental conditions of the laboratory. The plastic film is composed of many polymer groups with repeating chain links. After being molded and cooled, the macromolecular chain is temporarily frozen, and it takes a certain time for the molecular chain to fully stretch. The speed of the stretch is closely related to the environmental temperature and humidity. Therefore, the state of the sample should be adjusted under the standard environment of the test, and the test should be performed in this state, so that the test results are comparable. The state of the sample and the test standard environment are adjusted and set according to the standard environment and normal deviation range specified in GB/T 2918-1998 "Standard environment for plastic sample state adjustment and test", that is, the temperature is (23 ± 2) ℃, The relative humidity is (50±10)%. It should be noted that the adjustment time cannot be less than 4h.

Sampling requirements

Sampling shall be in accordance with relevant technical standards and specifications, and experimental samples shall be drawn from the test objects. Sampling includes the collection of test objects (sampling) and the preparation of test samples (sample preparation).

Sampling requires that the samples taken are representative and uniform, and the characteristics of all samples are estimated and inferred through the detection of the samples. This is a cost-effective method commonly used in scientific experiments, quality inspections, and social surveys.

Sample preparation refers to the processing of samples into standardized samples with uniform characteristics that can be used for test operations according to the purpose of the test. The prepared samples must also be representative to truly reflect certain characteristics of the analyzed materials.

Sampling is the condition to ensure correct testing. The representativeness and uniformity of sampling reflect the quality of batch products. The standardization of sample preparation ensures the reproducibility of test results and the comparability of test data. It is worth noting that the samples taken during the sampling process should be intact and the number of samples taken should be sufficient to complete all test items.