Synthesis Process of PVDF

Polyvinylidene Fluoride (PVDF) is a high-performance polymer material with excellent chemical resistance, heat resistance, corrosion resistance and electrical insulation, etc. It is widely used in the fields of chemical industry, electronics and medicine. The following is the synthesis process of PVDF:

1. Raw material preparation: the raw material of polyvinylidene fluoride (PVDF) is vinylidene fluoride monomer (VFVM), whose chemical formula is CH2=CF2. VFVM is usually polymerized by hydrofluoric acid catalyst.

2. Polymerization reaction: Put the vinylidene fluoride monomer into the reactor, add appropriate amount of solvent (such as NMP), and add the polymerization catalyst (such as benzoyl peroxide). Under a certain temperature, the polymerization reaction is carried out by stirring or gas phase polymerization to produce polyvinylidene fluoride.

3. Treatment: After polymerization, PVDF usually requires post-treatment, including the removal of residual monomers, by-products and impurities, as well as the adjustment of molecular weight and molecular weight distribution. Common treatment methods include dissolution, precipitation, washing, drying, etc.

4. Molding process: The treated PVDF can be molded by extrusion, calendering, injection molding and other processing methods. Among them, extrusion is one of the most commonly used processing methods, by heating PVDF particles to a molten state and then extruding them into molding. In addition, PVDF can be blended with other materials to prepare composite materials.

It should be noted that the synthesis process of PVDF is affected by factors such as reaction temperature, pressure, reaction time, catalyst type and concentration, which need to be adjusted and optimized according to specific requirements. In addition, PVDF is susceptible to side reactions during the polymerization reaction, generating branching structures and irregular polymers, so appropriate polymerization conditions and treatments are needed to control molecular weight and molecular weight distribution.