After hydrophilic modification, the key to maintaining the stable performance of polymeric microfiltration membranes lies in establishing strong interfacial interactions and multiple defense mechanisms.

After hydrophilic modification, the key to maintaining the stable performance of polymeric microfiltration membranes lies in establishing strong interfacial interactions and multiple defense mechanisms.

The core strategy involves constructing an interpenetrating polymer network (IPN) in which hydrophilic modifiers—such as microgels or hydrogels—are firmly anchored to the membrane matrix via covalent bonds or topological entanglements, thereby preventing their loss during dynamic shear or water washing. For example, a PVDF membrane can be engineered in situ using a spray-assisted non-solvent-induced phase separation (SANIPS) method to create a dual-network hydrogel-PVDF IPN structure, significantly enhancing its mechanical strength and chemical stability.

Surface grafting is another effective approach that involves grafting hydrophilic polymer chains (such as PVA or PIC) onto the membrane surface via methods like “click” chemistry or silanization, forming covalent bonds to ensure that the modified layer remains stable even under extreme pH conditions or high pressure. This dual-defense mechanism—comprising a hydration layer plus an ion brush—works synergistically to resist pollutant adsorption.

In addition, blending modification—by mixing hydrophilic components (such as SPSF) with the matrix material—can simultaneously enhance both hydrophilicity and film-forming properties. However, it is essential to precisely control the content of the hydrophilic component to avoid clogging the pores.

Do you need a comparison table of hydrophilic modification methods? We can help you quickly identify the most suitable technical approach for your membrane material.