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Polyvinyl Alcohol (PVA) Filament for 3D Printing
Overview
Polyvinyl Alcohol (PVA) is a water-soluble synthetic polymer widely used as a support material in 3D printing. It is particularly popular for its ability to dissolve in water, making it ideal for complex prints that require support structures which can be easily removed.
Advantages
- Water Solubility: PVA dissolves easily in water, allowing for the effortless removal of support structures without damaging the main print.
- Biodegradability: PVA is biodegradable and environmentally friendly, making it a sustainable choice for support material.
- Good Adhesion: PVA adheres well to a variety of materials, including PLA, ABS, and PETG, enhancing print quality and stability.
- Non-Toxic: Safe to handle and use, PVA is non-toxic and suitable for various applications.
Disadvantages
- Moisture Sensitivity: PVA is highly sensitive to moisture and must be stored in a dry environment to prevent it from absorbing water from the air.
- Limited Temperature Range: PVA has a lower melting point compared to other filaments, which can limit its use with high-temperature materials.
Technical Specifications
- Density: 1.19 g/cm³ (74 lb/ft³)
- Dielectric Constant (Relative Permittivity): 6.0
- Dielectric Strength (Breakdown Potential): 17 kV/mm (0.67 V/mil)
- Elastic (Young’s, Tensile) Modulus: 2.0 GPa (0.29 x 10⁶ psi)
- Elongation at Break: 15%
- Flexural Modulus: 1.5 GPa (0.22 x 10⁶ psi)
- Flexural Strength: 60 MPa (8.7 x 10³ psi)
- Glass Transition Temperature: 85°C (185°F)
- Melting Onset (Solidus): 190°C (374°F)
- Shear Strength: 45 MPa (6.5 x 10³ psi)
- Specific Heat Capacity: 1700 J/kg-K
- Strength-to-Weight Ratio: 45 kN-m/kg
- Tensile Strength: Ultimate (UTS): 55 MPa (8.0 x 10³ psi)
- Thermal Conductivity: 0.21 W/m-K
- Thermal Diffusivity: 0.18
- Thermal Expansion: 75 µm/m-K
- Water Absorption After 24 Hours: 10%
Material Properties for 3D Printing
- Printing Temperature: 180-220°C
- Flow Tweak: 0.92
- Bed Temperature: 60°C
- Bed Preparation: Apply two layers of glue stick for optimal adhesion
Features
- Soluble Support Material: PVA is primarily used as a support material that dissolves in water, allowing for the creation of complex structures without the need for manual support removal.
- Compatible with Multiple Filaments: Works well with PLA, ABS, PETG, and other common filaments, providing versatile support options.
- Easy Removal: Once printing is complete, simply immerse the print in water to dissolve the PVA supports.
Additional Considerations
- Storage: Store PVA filament in a sealed container with desiccant to prevent moisture absorption, which can lead to printing issues.
- Print Quality: Ensure proper bed adhesion and optimal printing conditions to achieve high-quality prints.
- Dissolution Process: After printing, soak the printed object in water to dissolve the PVA supports. The dissolution process may take several hours depending on the volume of PVA used.
Application Examples
- Complex Geometries: Ideal for printing complex geometries and intricate designs that require support structures.
- Mechanical Parts: Useful for creating mechanical parts with internal cavities or overhangs that need support during printing.
- Prototyping: Suitable for rapid prototyping where ease of support removal is essential.
By understanding these properties and considerations, you can effectively use PVA in your 3D printing projects to achieve clean, high-quality results with easy-to-remove support structures.
PVA remains a preferred choice for support material in 3D printing due to its water solubility, ease of use, and compatibility with various filaments, making it an essential material for complex and high-precision prints.