How to maintain the waterproof and breathable membrane

When the membrane is stored for a long time, it must maintain good performance and have use value, so the life of the waterproof and breathable membrane is an important issue. Therefore, special attention should be paid to the actual storage. The preservation of the waterproof and breathable microfiltration membrane is divided into two methods: wet preservation and dry preservation. Either way, the purpose is to prevent hydrolysis of the membrane, prevent the growth and erosion of microorganisms, and shrinkage and deformation of the membrane.

The key to wet preservation is to always make the membrane surface attached with preservation liquid, in a moist state. The following formula can be used for the preservation solution: water: glycerin: formaldehyde = 79.5: 20: 0.5. The function of formaldehyde is to prevent the growth and reproduction of microorganisms on the surface of the membrane and to prevent erosion of the membrane. The purpose of adding glycerin is to reduce the freezing point of the preservation solution and prevent the membrane from being damaged by freezing. The formaldehyde in the formula can also be replaced by other fungicides such as copper sulfate that are not harmful to the membrane. The storage temperature of cellulose acetate membrane is 5-40°C and pH=4.5~5, while the storage temperature and pH of non-cellulose acetate membrane can be wider.