What is PVDF?
PVDF is a semi-crystalline thermoplastic fluoropolymer.
What are the production methods for PVDF?
PVDF is generally synthesized through free radical polymerization of 1,1-difluoroethylene (CH2=CF2) in the suspension or emulsion.
What are the properties of PVDF?
PVDF has a crystal structure and exists in four possible conformations named α, β, γ, and δ phases. It has high mechanical strength and is non-flammable. It also exhibits good resistance to UV light and chemicals.
What are the electrical properties of PVDF?
PVDF has high dielectric constant and dissipation factor, making it suitable for wire and cable isolation. It can also exhibit piezoelectric and pyroelectric behavior.
How can PVDF be processed?
PVDF can be processed using techniques applicable to standard thermoplastics, such as extrusion, injection molding, compression molding, transfer molding, and machining.
Does PVDF require drying before processing?
Drying of PVDF resin before processing is usually not necessary.
What is the recommended temperature range for processing PVDF?
The processing temperature for PVDF is between 190 to 280°C for various processing methods.
What are the recommended parameters for injection molding PVDF?
The melt temperature for injection molding PVDF should be between 200-270°C, and a mold temperature of 50-95°C is recommended. Proper mold design is important due to the relatively high melt viscosity of PVDF.
What precautions should be taken during extrusion of PVDF?
Attention should be paid to eliminating dead spots where degradation of the polymer can start. The extrusion temperature for PVDF ranges from 230 to 290°C, and no extrusion aids, lubricants, or heat stabilizers are needed.
What is the recommended L/D ratio for extrusion of PVDF?
An L/D ratio of at least 20 is recommended for extrusion of PVDF.
