Abstract: Waterproof and breathable membranes are widely used in the following fields:
- Construction industry: used for external wall insulation system of buildings, roofing, basement waterproofing, etc., can achieve waterproof and breathable effects at the same time.
- Packaging industry: Used in packaging materials such as textiles, electronic products, food, etc., which can protect products from moisture and at the same time have breathability.
- Apparel industry: used in outdoor sportswear, raincoats, etc., can provide waterproof performance and discharge sweat vapor from the human body at the same time.
- Agricultural field: used for greenhouse covering materials, agricultural protective films, etc., which can prevent water retention and maintain a suitable humidity environment.
Keywords: waterproof breathable membrane, composite membrane, moisture resistance, moisture resistance, weighing method, water vapor transmission rate, water vapor transmission rate tester
1.The importance of water vapor transmission rate testing of waterproof and breathable membranes:
The water vapor transmission rate test is one of the key indicators for evaluating the breathability of waterproof and breathable membranes. Specific importance includes:
- Guarantee the comfort of the human body: as a part of the clothing, the waterproof and breathable membrane has a water vapor transmission rate that determines the humidity regulation and comfort when the human body perspires. The high water vapor transmission rate can promote the release of sweat, keeping the body dry and comfortable.
- Prevent internal moisture retention: In the field of building waterproofing, the water vapor transmission rate of the waterproof breathable membrane determines whether the indoor moisture can be discharged. Proper water vapor transmission rate can prevent indoor moisture stagnation and reduce damage caused by humid environments, such as mold growth and decay.
- Protecting the contents of the package: In the packaging industry, the water vapor transmission rate test of the waterproof and breathable film can judge its breathability, avoid the generation of moisture inside the package, and thus protect the product from the influence of moisture and corrosion.
2.Importance to enterprise production:
The importance of water vapor transmission rate testing to enterprise production lies in:
- Guarantee product quality: The water vapor transmission rate test can verify whether the performance of the waterproof and breathable membrane meets the design and specification requirements, ensuring stable product quality and performance.
- Improve market competitiveness: Qualified waterproof and breathable membranes can meet market demand, provide high-quality products, and enhance the market competitiveness of enterprises.
- Reduce quality risk: Through water vapor transmission rate testing, problems with waterproof and breathable membranes can be detected and corrected early, reducing possible quality risks during product use.
- Compliance with regulations and standards: Many industries have specifications and standards for waterproof and breathable membranes. Water vapor transmission rate testing can help companies comply with relevant regulations and standards.
- Building trust and brand image: Qualified waterproof and breathable membrane can prove to customers the quality management control of the enterprise and establish a good trust and brand image.
3. Water vapor transmission rate test process of waterproof and breathable membrane:
At present, the test methods for the water vapor transmission rate of waterproof and breathable membranes include the weighing method (cup method), electrolysis method, humidity method and infrared method.
The detection equipment used in this paper is the GBPI W812 water vapor transmission rate tester.
This product is based on the test principle of water vapor transmission by cup method, designed and manufactured in accordance with ASTM standards, and provides a wide range of high-efficiency water vapor transmission rate testing for low, medium, and high water vapor barrier materials tests.
scope of application
(1) This equipment is suitable for testing the water vapor transmission rate of films, sheets, paper, cardboard, textiles, non-woven fabrics, and other materials.
Films: various plastic films, waterproof and breathable films, plastic composite films, paper-plastic composite films, geomembranes, co-extruded films, aluminized films, aluminum foil, aluminum-plastic composite films, and other film materials.
Sheet materials: various engineering plastics, rubber, building materials, thermal insulation materials, and other sheet materials, such as PP sheets, PVC sheets, PVDC sheets, nylon sheets, etc.
The water vapor transmission rate test is usually carried out with testing instruments, which mainly includes the following steps:
- Sample preparation: Cut out a sample with a certain size from the waterproof and breathable membrane to ensure that the sample is flat and undamaged.
- Measuring equipment setup: set up the testing equipment and adjust the corresponding parameters such as temperature, humidity, and pressure, etc.
- Sample installation: Install the sample in the test instrument to ensure complete sealing and avoid interference from external factors.
- Test start: run the test equipment, make the sample under certain temperature and humidity conditions, gradually form water vapor penetration, and measure the penetration amount within a certain period of time.
- Data recording and analysis: record the data during the test, and calculate the water vapor transmission rate index according to the standard requirements.
- Result Judgment: Compare the test results with the requirements of relevant standards to judge whether the water vapor transmission rate of the waterproof and breathable membrane meets the requirements.
