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GB/T 1037 is the Chinese national standard "Plastic film and sheeting - Determination of water vapor transmission rate". It mainly specifies the test method for determining the water vapor transmission rate of plastic film and sheeting under certain temperature and humidity conditions. The following is a brief introduction to the main content and measurement method of the standard:

Introduction to the standard

Standard name: GB/T 1037-2011 Plastic film and sheeting - Determination of water vapor transmission rate performance - Cup weight gain and weight loss method

Issuing unit: China National Standardization Administration

Scope of application: Applicable to the determination of water vapor transmission rate of plastic film and sheeting under certain temperature and humidity conditions.

Measurement principle

GB/T 1037 specifies the test principle of water vapor transmission rate, that is, under constant temperature and humidity conditions, the amount of water vapor passing through the sample is determined. The test is mainly carried out by cup weighing method and weight loss method.

Test method

1. Cup weighing method

Test equipment: Water vapor transmission rate tester.

Sample preparation: Cut the sample to be tested into the specified size and install it in the test device.

Test steps:

Place the test device in a constant temperature and humidity environment.

Maintain a constant water vapor concentration at the water vapor source end of the test device.

Record the amount of water vapor passing through the sample within a certain period of time.

Calculate the water vapor transmission rate (WVTR) in g/m²·day.

2. Cup weight loss method

Test equipment: Water vapor transmission rate tester with weighing sensor.

Sample preparation: Same as weighing method.

Test steps:

Place the test device in a constant temperature and humidity environment.

Maintain a constant water vapor concentration at the water vapor source end of the test device.

Detect the amount of water vapor passing through the sample through the weighing sensor.

Calculate the water vapor transmission rate.

Calculation formula

WVTR=G/A*t ?

WVTR: Water vapor transmission rate, in g/m²·day.

G: The total amount of water vapor passing through the sample during the test time, in g.

A: The effective area of ??the sample, in m².

t: Test time, in day.

Notes

Environmental control: Keep constant temperature and humidity during the test.

Sample preparation: The sample should be kept flat, free of damage and contamination.

Equipment calibration: Calibrate the test equipment regularly to ensure the accuracy of the test results.

GB/T 1037 standard provides a standardized method for measuring the water vapor transmission rate of plastic films and sheets to ensure the consistency and reliability of the test results. For electronic product packaging materials, it is crucial to control the water vapor transmission rate to prevent moisture from affecting electronic components.