How to identify true and false waterproof breathable membrane

1. Laboratory testing

Test items:

a. Temperature resistance; b. Water vapor transmission rate (ie air permeability); c. Hydrostatic pressure; d. Anti-aging ability.

The real waterproof and breathable membrane is not compounded with glue, so the temperature resistance is -40, 100 degrees (CE standard of the European Union, ASTM standard of the United States). It is not produced with polyethylene or TPO coating, so the air permeability should exceed 1500g/square/24 hours, and it is basically airtight if it is produced with polyethylene or TPO coating.

For hydrostatic pressure testing, the hydrostatic pressure of thin waterproof and breathable membranes should be at least 1.5 meters, and that of thick waterproof and breathable membranes should be at least 2 meters.

Anti-aging is a must, because PP materials are prone to aging under ultraviolet light. Some counterfeit waterproof and breathable membranes are produced with poor recycled materials. This waterproof and breathable membrane is easily aged and degraded during construction.

2. Simple hands-on inspection

On the surface, there are obvious pressure points on both sides of the waterproof and breathable membrane. That is because the production process is through hot pressing and lamination. Please note that it is not the dot pattern of the non-woven fabric itself, but the obvious overlapping dot pattern.

To tear apart the waterproof and breathable membrane, first of all, the middle polymer layer should be a milky white and soft waterproof and breathable layer. Because it is laminated by heat and pressure, there should be pressure points on this layer of membrane.

In addition, lightly press the non-woven fabric and the membrane with your hands. If there is a sticky feeling, then it can be concluded that it is hot-melt adhesive adhesion, then this is a fake waterproof and breathable membrane. Because the hot melt adhesive sticks even at normal temperature, the three layers of materials will bubble and delaminate soon, and will be peeled off automatically.