Recently, the plastic film physical property data comparison activity initiated by Labthink and participated by 125 laboratories worldwide has officially come to a successful conclusion. This borderless public welfare activity, which has persisted for 12 years, has continuously broken the scale record of industry data comparison activities. Through the precise collision of thousands of sets of data, it has effectively promoted the standardization process of global laboratory barrier performance testing capabilities.

Comparison of Barrier Test Data: Significant Discrepancy and Obvious Range

Compare Project 1 Oxygen Transmittance Rate

104 laboratories provided feedback on a total of 123 sets of data, of which 2 laboratories did not participate in the evaluation due to underreporting the results of one sample; The testing data from 7 laboratories showed significant differences compared to other laboratories, and were determined to be incorrect data and will not be included in the statistics.

Comparison results:

• The test results of 8 laboratories showed outliers within the laboratory;

• The test results from two laboratories are suspicious within the laboratory;

• The test results from 5 laboratories are suspicious between laboratories.

Compare the water vapor transmission rate of Project 2

109 laboratories provided feedback on 133 sets of data, of which 2 laboratories did not participate in the evaluation due to underreporting the results of one sample; The testing data from 7 laboratories showed significant differences compared to other laboratories, and were determined to be incorrect data and will not be included in the statistics.

Comparison results:

• The test results from one laboratory are suspicious within the laboratory.

From the overall distribution of data, there are significant differences in test results between different laboratories, and even obvious deviations from normal data. The main influencing factors are as follows:

• In terms of testing methods, differential pressure method (80 laboratories) and isobaric method (41 laboratories) are mainly used for oxygen permeability detection, while cup method (65 laboratories) and infrared method (55 laboratories) are mainly used for water vapor permeability detection. Different methods may lead to differences in results.

• The testing instruments used in this barrier data comparison activity mainly come from many manufacturers such as Labthink, MOCON, BRUGER, Guangzhou Standards, etc. Therefore, in terms of instrument calibration, the lack of unified standards among manufacturers and the adoption of different calibration methods can result in certain data deviations.

• The stability of device performance is particularly critical, and it is recommended to regularly check the sensor status with a standard membrane, especially for devices that are used too frequently or restarted after a long period of shutdown.

• The laboratory environment control must be strictly maintained within the range of (23 ± 2) ℃ and (50 ± 5)% RH, as temperature and humidity deviations can directly affect data accuracy.

• Oxygen permeation testing requires the use of high-purity gas to avoid interference from impurities, while also paying attention to random error factors such as personnel operation.

Overall, standardized testing procedures, equipment maintenance, and environmental control are key to ensuring the reliability of test results.

Comparison of tensile performance test data: large dispersion, results are relatively small

116 laboratories provided feedback on 118 sets of tensile strength testing results and 114 sets of nominal strain testing results for fracture. The tensile strength results and fracture nominal strain results of three laboratories are significantly different from those of other laboratories, and are judged as erroneous data and will not be included in the statistics.

Comparison results:

• Tensile strength project -2 laboratories have suspicious test results, and 3 laboratories have outlier test results;

• Fracture nominal strain item -1 laboratory test result is suspicious, 6 laboratory test results are outlier.

From the overall data distribution, it can be seen that the tensile strength and fracture nominal strain test results of some laboratories are relatively small. Labthink suggests that in such project testing, the following key steps should be systematically investigated:

• Firstly, ensure the stability of the instrument performance and regularly check and calibrate the force sensor and displacement sensor;

• Secondly, strictly control the temperature and humidity of the laboratory environment within the standard range of (23 ± 2) ℃ and (50 ± 5)% RH;

• During the sample preparation process, special attention should be paid to the flatness and edge treatment of the sample to avoid wrinkles and burrs that may affect data accuracy;

• In terms of operating standards, the tightness of the fixture should be checked to prevent the sample from slipping or being damaged;

• For abnormal data, it is recommended to analyze the reliability based on the test curve, with a focus on checking the equipment parameter settings (such as the fact that the abnormal nominal strain caused by fracture is mostly due to incorrect parameter settings), and reduce random errors by increasing the test sample size;

• The laboratory should establish a multidimensional quality control system, including equipment maintenance, environmental monitoring, standardized operations, and personnel training, with particular emphasis on technical consistency among different operators.

For laboratories with questions about the results, please feel free to contact us at any time. Labthink will provide comprehensive barrier testing data consulting services for participating laboratories to help them solve various problems encountered during the experimental process.

Thus, the 12th Labthink Global Inter Laboratory Physical Performance Data Comparison Activity for Plastic Films has come to a successful conclusion.

Looking forward to the next gathering in 2026!