GB/T 31355-2014Determination of water vapor transmission rate through dry packages—Mmodulated infrared sensor (English PDF)

1 Scope

This standard specifies under steady state conditions using an infrared sensor package and method for testing water vapor permeability container Test method.

This standard applies to plastics and composites packages and containers (hereinafter referred to as the package) water vapor permeability testing.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version suitable for use herein

Member. For undated references, the latest edition (including any amendments) applies to this document.

GB/T 2918 plastic sample conditioning and testing of the standard environment (GB/T 2918-1998, ISO 291.1997, IDT)

3 Terms and Definitions

The following terms and definitions apply to this document.

4 Test principle

The package is mounted on the instrument, and the opening was sealed packages. Drying the carrier gas through the inside of the package, the package is placed on the outside of the known phase

Humidity environment. Since the inside and outside of the package there is a certain difference in humidity, water vapor from the high humidity side, low humidity to seep through the side wall of the package through. Through the wall of water vapor package transmitted together with a carrier gas to the infrared sensor, the sensor measures the infrared energy absorbed by the water vapor in the

Ratio, produces an electrical signal of a certain intensity, concentration and strength of the electrical signal is proportional to water vapor. Within a certain time by detecting electrical signals

The strength of water vapor transmission rate of the sample is calculated.

5 Sample

The sample should be representative, to ensure a good seal. Creases or other defects affect the test results.