NKY® PVP K

The molecular structure of PVP: 

NKY® PVP Specifications:

The physicochemical properties of NKY® PVP:

A water-soluble polymer that is miscible with water and can dissolve in many organic solvents such as alcohols, carboxylic acids, amines, and halogenated hydrocarbons.

Possesses good initial viscosity.

Exhibits excellent film-forming properties.

Has strong water absorption and moisture retention capabilities.

Low molecular weight PVP has good dispersing effects, preventing particle aggregation and sedimentation.

Increases the solubility of many substances in aqueous solutions.

Displays good biocompatibility and toxicological safety.

Which film-forming polymers can utilize NKY® PVP for pore formation and modification?

PVP is a water-soluble polymer compound with excellent solubility, biocompatibility, complexation, film-forming, adhesive capabilities, and water absorption and moisture retention properties. Therefore, it can be co-dissolved with many film-forming polymers in the same casting system to prepare flat membrane and hollow fiber membrane. Common polymers used include: Polyvinylidene fluoride(PVDF), polysulfone (PSU), polyvinyl alcohol (PVA), cellulose acetate, chitosan, polyphenylene sulfide (PPS), polypropylene (PP), polyimide (PI), and others. Among the polysulfone category, there are: PSU, PES, sulfonated polysulfone (SPES), poly(ether ether ketone) (PEEK), and poly(phenylene ether sulfone ketone) (PPESK).

The Role and Application of NKY® PVP in Separation Membranes

PVP is widely used in the membrane production process for pore formation, controlling pore structure, adjusting the permeability and hydrophilicity of the membrane surface. NKY offers a series of PVP products under the brand name NKY®, which can meet various viscosity and molecular weight requirements.

Membrane prepared by combining NKY® PVP with polyvinylidene fluoride (PVDF), polyether sulfone (PES), polysulfone (PSU), and other polymers exhibit good chemical stability and heat resistance, high porosity and permeability, better control over pore size and distribution, enhanced hydrophilicity of the membrane surface, and improved biocompatibility and antifouling properties. Additionally, various membranes containing PVP can undergo crosslinking with PVP/VA series under suitable temperatures, ultraviolet light, X-rays, and hydrogen peroxide, which further enhances the hydrophilicity of the membrane surface.

NKY® PVP Pore Formation Principle:

Utilizing the ternary phase separation principle, the casting solution is prepared by dissolving the main polymers such as polysulfone and PVP in dimethylacetamide (DMAc). During the phase inversion process, water acts as a solvent to control the precipitation and solidification of the polymers. The proportion of high molecular weight polymers used in the membrane spinning process and the precise thermodynamic conditions determine the final membrane structure.

The Membrane Formation Mechanism of Ternary Phase Separation

What can the R&D team of NKY do for you?

Boai NKY can provide high-quality NKY series products and commonly used solvents, such as NKY® 2-Pyrrolidone (2P); it can also supply high-quality crosslinked PVP (i.e., PVPP), PVP/VA64, and a series of other copolymer products.

Our R&D team can offer you proactive technical support and provide suggestions for improving the performance of your products.

Other product recommendations for membrane applications:

For adsorption membranes, PVPP can be used.For hydrophilic modification, VA64 and VA73 are recommended.