What are PVDF and the PVDF filter membrane?

What is PVDF?

Polyvinylidene fluoride (PVDF)’s appearance is a translucent or white powder or particles, molecular chains are closely arranged, and there are strong hydrogen bonds. Its oxygen index is 46%, non-combustible, crystallinity is 65%~78%, density is 1.17~1.79g/cm3, melting point is 172℃, heat distortion temperature is 112~145℃, long-term use temperature is -40~150℃.

PVDF is a PVDF fusible fluorocarbon resin for coatings made by the homopolymerization of vinylidene fluoride (VDF) with a purity of ≥99.99%. The fluorocarbon coating made of 70% PVDF resin is sprayed or rolled and baked into the paint film, which has super weather resistance and processing performance.

PVDF not only has strong wear resistance and impact resistance but also has high fading resistance and UV resistance in extremely harsh and harsh environments. PVDF is currently the second-largest product among fluoroplastics, with an annual global production capacity of more than 43,000 tons.


What is a PVDF filter membrane?

PVDF filter membrane is solid support commonly used in western blotting. Use 0.45um membrane for protein larger than 20000, and 0.2um membrane for protein smaller than 20000. PVDF membranes need to be pre-treated in use. To activate the positively charged groups on the membrane, making it easier to bind negatively charged proteins, is the methanol treatment’s purpose.

PVDF filter membrane has high mechanical strength and is an ideal solid support material in the imprinting method. Its performance is better than pure PVC membrane material, and the price is correspondingly slightly higher than pure PVC membrane material. Compared with ordinary PVC membranes, PVDF membrane has improved durability to about 7~10 years.

Classification of PVDF filter membrane

1. For water treatment, there are two types of ultrafiltration membranes and microfiltration membranes. They are mainly used for pre-treatment of sewage, seawater desalination, etc., to remove macromolecules, bacteria, silt, etc.
2. For outdoor construction, the main user is the protection of outdoor construction glass, exterior walls, outdoor billboards, etc., mainly for aging resistance and wear resistance.
3. For batteries, it includes membrane applications in fuel cells and lithium-ion polymer batteries.

The main performance of the PVDF filter membrane

· High mechanical strength and toughness
· Anti-fungal
· High abrasion resistance
· High resistance to gas and liquid permeability
· Good heat stability
· Flame retardant, low smoke
· Good creep resistance during the temperature increase
· High purity
· Easy to melt processing
· Resistant to most chemicals and solvents
· Both rigid and flexible form
· UV and nuclear radiation resistance
· Impact resistance
· Weather resistance
· Low temperature resistance up to -40℃