These days there are many kinds of paints, surfaces, pouring mediums, and additives that acrylic pouring artists use to create with. Each of these items has its strengths, weaknesses, and associated monetary costs. With this in mind, we are exploring one of the more inexpensive, but highly effective, pouring mediums commonly available to most artists; PVA glue.
PVA, or polyvinyl acetate, glue works quite well as a pouring medium. The texture and composition mix nicely with acrylic paints and dries into a sturdy, slightly flexible, solid that adheres to many different painting surfaces. PVA glue is also relatively inexpensive and easy to find in most countries.
Read on for more information about the composition of PVA glue and a few of the advantages and disadvantages of using PVA glue in your fluid acrylic pouring project.
Why Use PVA Glue in Acrylic Pouring?
PVA glue is a multi-purpose glue made from polyvinyl acetate. This glue is most commonly used as an adhesive to porous materials like wood, cloth, paper, and cardboard.
Vinyl and acrylic resins are similar in composition with vinyl being a much cheaper alternative, hence its use in things like house paint and glue. The vinyl resin is both a hardener and a binder which makes it an ideal candidate for extending acrylic paint without compromising its strength and composition.
Here are a few of the other properties of PVA glue to consider before using it as a pouring medium.
One major factor in favor of using PVA glue for your acrylic paint pour is the price. All-purpose glue like Elmer’s Glue-All can be found any almost any hardware, grocery, or convenient store. This glue costs a fraction of the price of most name brand acrylic paint pouring mediums.
When used in an acrylic paint pour, glue tends to have fewer cells form naturally when compared to other pouring mediums like Floetrol or Liquitex Pouring Medium. This is especially beneficial when you are looking to get more solid colors in your paint pour techniques like a ring pour.
Cells are a tricky business with fluid art and we recommend you read our article specifically dedicated to cells here.
Strength and Drying Times
PVA glues were created to improve the strength of the glue and to minimize their drying times. PVA glues are made of binders/resins, water, and ethanol or acetone.
The binders/resins create the bonding connection between surfaces. The water gives the mixtures it’s fluidity and contributes to how long the material takes to dry. The ethanol or acetone is used to control how quickly the glue dries.
Drying times for acrylic pour artists are less important than a woodworker where minutes can be important. Acrylic pour artists expect their paintings to take a day or two to dry and a few weeks to fully cure. You can learn more about drying times of acrylic pours in our article here.
Glue Provides Sheen
Since many acrylic paints are more matte, when combined with a pouring medium made of semi-gloss glue and water you get a shinier result when dried.
PVA Glue is Non-Toxic
Another plus for using PVA glue as your pouring medium is that it is non-toxic. These glues are made from synthetic materials that do not create very much outgassing. No special equipment like masks or gloves is required when using PVA glue.
Common Ratios for Using PVA Glue in a Pouring Medium
Many acrylic paint pouring artists us PVA glue as the base of their pouring medium. Here are a few of the most common ratios we have seen for a pouring medium. PVA glues are usually quite thick so water or another liquid is added to give the medium a less viscous consistency.
- 2/3 PVA Glue – 1/3 Water
This is the most common recipe for using a PVA glue like Elmer’s Glue-All in a pouring medium that we have seen. The ratios are relatively easy to eyeball without needing to use a scale.
- 70% PVA Glue – 30% Water
This is the ratio we use most often in our painting with a medium made from PVA glue. This gives a slightly thicker consistency that works well for any pour that you want the colors to stay a little bit more solid and not intermix as much. A tree ring pour is one of the pours we like to use this mix on.
- 50% PVA Glue – 25% Water – 25% Floetrol
This is the mixture we use when doing a flip cup or a dirt pour where we want some small natural cell to come out. This also works well with a swipe as it produces some pretty spectacular lacing.
For craft paints, we mix a 1:1 ratio of paint to glue-based medium. For student quality acrylic paints the ratio is 1:2 parts paint to pouring medium. Heavy body acrylics and professional paints the ratio goes up to 1:3 or 4 depending on how vibrant you want the colors to look.
NOTE: Most glue looks slightly opaque (or misty white). When added to acrylic paints the colors will look lighter. When the glue dries, it will dry clear and your colors will show brighter than they looked in the original liquid mixture. Keep that in mind when mixing your acrylic pour paints with a glue-based medium.
Don’t forget to read our Best Acrylic Paints for Pouring article to get insight into some of the great acrylic paint brands we use.
Additives for PVA Glue based Pours
- Silicone Oil
A drop of silicone per 2 oz of paint will help bring out cells in a pour with a PVA glue medium. You may need to torch the pour after it is on the canvas to help break the surface tension and allow the oil to filter to the top.
Torching early before tilting the canvas will allow for the cells to grow and be stretch the longest and therefore you’ll get the largest cells. Torching at the end of the pour, after the majority of your tilting is done, will give small and more round cells (since there is no tilting to make the odd shaped).
- Isopropyl Alcohol
Just a small amount of isopropyl alcohol added to a PVA glue medium will produce a lot of tiny cells. Do no torch a pour with alcohol in it as it may light it on fire.
Be warned the alcohol in opaque colors like white does tent to make that color dry blotchy. This is one additive we recommend practicing a fair bit with as it reacts differently to each paint and medium.
There are a few different types of PVA glue that you can use. Here I a list of the most common ones, at least the United States.
- Glue-All or White Glue – This is a multi-purpose glue that we use the most. Elmer’s is a popular brand in the US but there are a few others.
- School Glue – This a watered-down version of the Glue-All. It is made to be washable, even after it has dried which is why it is favored in-school use. This will work for practice pours but we don’t recommend using it for artwork you want to last longer than a few years. If you use silicone you can’t wash that off before putting a resin or top coat on or you will pull up the color. School Glue also dries a smoky white where Glue-All dries clear.
- Bookbinders Glue – This glue is specially made for long term use. It is PH neutral so that it won’t break down or yellow over time.
- Clear Glue – Some glue comes in a clear form. In most cases clear glue is similar to the Glue-All or white glue. Bear in mind that some school glues are also clear so read the label carefully.
Is PVA Glue Archival in Pour Paintings
Archival refers to the lifespan of a material and how well said materials keeps its original color, texture, and form. Because the composition of PVA glues varies from manufacturer to manufacturer, every glue is going to have a different archival quality.
Most PVA glues, like School Glue, Clear Glue, and Elmer’s Glue-All are slightly acidic. These glues will last years but will break down over time in part because of the acid. However, based on what we’ve seen from other artists, this time tends to be in the decades for acrylic pour art.
Many fine artists prefer book binder’s glue or other similar acid-free or PH neutral glues as they will last much longer than traditional glues. Bookbinders and acid-free glues are also more expensive than more common PVA glues.