PVA Filament in 3D Printing: Properties, Uses, and Key Advantages

In the 3D print sector, PVA 3D filament (polyvinyl alcohol) is a critically important family of materials. Its water solubility is very valuable because it allows support scaffolds to be printed on dual/multi extruder machines and later removed with ease. PVA offers several useful characteristics that make it almost perfect as a support material. These include: high water solubility, high stickiness in the melted state, and a print temperature range of 180-210°C. 

PVA was first produced by Fritz Klatte and patented in Germany in 1912. Initial commercialization occurred in Japan in the late 1930s, with the Kuraray company producing low-cost Vinylon and Kuralon fibers. These came in various levels of insolubility and each fit a different application. Some of the PVA fibers were made to: modify concrete, reinforce rubber, or enable fiberglass to better resist shock and shrinkage. 

PVA’s basic form is powder. The 3D print filament is formed by melting and extruding that basic material. This filament is very uniform in its properties and is sold in packaging that prevents exposure to atmospheric moisture. Such exposure would degrade the material and make the filament rolls congeal into a softened mass. This article will further discuss PVA 3D printing filament and examine its composition, properties, and recommended 3D printer settings.

What is PVA 3D Printing?

Within the realm of 3D printing, PVA is solely used to construct support scaffolds. It serves to support structures that would otherwise be impossible or ungainly to print. Once the printing is finished, the supports can be washed away. PVA supports are extruded by a second extruder but are otherwise built up in exactly the same way as the part’s primary material. For more information, see our guide on everything you need to know about 3D printing.

What is the Composition of PVA Filament?

The typical PVA 3D printing filament available on Amazon is either pure PVA (polyvinyl alcohol) from a single source or a blend of several PVA materials. These PVA materials are meant to achieve the right balance of adhesion, strength, water solubility, and melt-flow characteristics. PVA is a synthetic polymer derived from the hydrolysis of polyvinyl acetate with the nominal formula [CH2CH(OH)]n.  

Filament for 3D printing is supplied in various diameters, but it is chemically pure PVA without any additives and co-polymers other than coloring agents. Some variation in molecular weight is normal between manufacturers – it varies based on the n value in the chemical formula. This variation in molecular weight affects melt temperature and density, so Esun PVA filament may not have exactly the same characteristics as Flashforge PVA filament, for example.

What Are the Properties of PVA Filament?

Some of the desirable properties of PVA filament are:

1. White in appearance (unless colored by addition).
2. Translucent.
3. Resistant to organic solvents and oils.
4. Highly water-soluble, depending on the degree of hydrolysis in its manufacture and its molecular weight.
5. Highly rated for tensile strength, compared with many polymers used in 3D printing.
6. More flexible and wear-resistant than many other polymers.

Comparison of PVA Filament Properties

A comparison of the PVA filament properties to HIPS (high impact polystyrene) and ABS (acrylonitrile butadiene styrene) is shown in Table 1 below: