How to Seal Acrylic Paint on Plastic?

To seal acrylic paint on plastic, you must apply a primer before you start painting the surface. Once you’re finished with the coloring, you can use a clear sealant designed for acrylics and plastic surfaces. Varnish, Mod Podge, Elmer’s or Puzzle glue, hairspray, and even nail polish can be used as a sealant on plastic.

When the acrylic paint is completely dried on the plastic surface, apply a thin layer of sealant by spraying or using a synthetic brush. 

Let the sealer dry and apply another layer if needed. 

Although it seems easy to achieve, you must learn how to seal acrylic paint on plastic in the proper way. 

Let’s get into the details and learn the DIY method of sealing acrylic paint on plastic.

Suitable Products to Seal Acrylic Paint on Plastic 

You can apply acrylic paint on plastic, but the paint will fade or peel off in a very short time. It’s because plastic is a non-porous surface that doesn’t offer enough adhesion space for the paint.

So, if you want to make the paint long-lasting, you must seal the plastic surface with a suitable product.

Here are some useful sealants you can use on plastic − 

Acrylic Sealer for Plastic 

Many different brands have come up with their own formula to create special sealants for acrylic paint. Although most of them are created for all types of surfaces, it’s better to choose one particularly formulated for plastic.

You can either choose a clear sealant or choose colorful ones matching your art project. Besides, some sealants come in spray form, while some are suitable for brush-on application. 

We recommend choosing a clear sealant in aerosol spray form as it’s easy to apply and the colorless sealer doesn’t change the acrylic shades.

Mod Podge 

This multi-purpose decoupage glue works as a sealer and provides a glossy finish to the plastic surface. 

As it’s a water-based sealant, it dries quickly, taking about half an hour. Mod Podge has a white, somewhat opaque appearance and a glue-like smell. 

It creates a thick clear coat on the plastic, which hardens to seal the acrylic paint. This product also comes in spray form, which is easier to apply. 

Mod Podge will be a great option for sealing acrylic paint on plastic models if you have a low budget. You can also use it as a base to increase adhesion before applying the paint. 


Using varnish is probably the cheapest way of sealing acrylic paint on plastic. This sealant is composed of solvents, oils, and resins resulting in a thick adhesive substance. 

When applied to plastic, it creates a highly protective translucent coat that prevents acrylic paint from fading and chipping.

Liquitex professional satin varnish will be a good choice for plastic surfaces. It creates a smooth satin-like coat that protects the paint and enhances its longevity.


Only two layers of polyurethane can protect an acrylic-painted surface against dirt, chemicals, moisture, abrasion, temperature, and fungi. It forms a protective plastic-like layer over the paint that offers a very smooth finish as well.

While choosing between polyurethane types, go for water-based polyurethane instead of an oil-based one. Unlike oil-based polyurethane, water-based polyurethane isn’t prone to yellowing over time.

Elmer’s Glue

Also known as PVA glue, Elmer’s glue can also work as a sealant for plastic. However, it creates a thick opaque layer on the surface which might cover the paint too. 

So, you must thin the glue with water and use a lacquer spray after applying it to acrylic paint. You need to add one part water to two parts glue to get a perfect consistency. Elmer’s glue takes about 30 minutes to dry to touch. 


If you intend to keep the painted plastic indoors, hairspray can be a good choice for sealing the paint. Since hairspray will change color in the presence of sunlight. Therefore, it’s not a good option for outdoor projects.

Getting back to the point, water-based hairspray is fast-drying and easily available. 

It’s thinner than regular acrylic paint and takes only 5 to 10 minutes to evaporate. When dried, hairspray leaves a thin glossy layer that protects the acrylic paint on plastic. 

Nail Polish 

Believe it or not, nail polish works pretty well as a sealant for plastics. If you want a quick sealer and have no other option in hand, you can apply clear nail polish on the acrylic paint to prevent cracking and fading.

Although it might take some time, the end product will impress you with a glossy, satin-like finish.

Remember, a nail polish coat isn’t long-lasting or resistant to yellowing. So, you can use it as a temporary sealant only.

So yes, choose the sealer carefully. Also, be choosy while selecting acrylic paint. In case, you’re planning to mix another type of paint with acrylic paint, be careful because there are limitations. For example, you can’t mix enamel paint with acrylic paint.

How to Seal Acrylic Paint on Plastic DIY Method 

If you want to seal acrylic paint on plastic, you must prepare the surface before applying the paint. 

So, let’s start from the very beginning and find out how to apply and seal acrylic paint on plastic.

Step One – Prepare the Base 

  1. As mentioned, plastic is a non-porous surface which makes painting difficult. You need to prepare the base first for proper adhesion and coverage.
  2. Clean the plastic object with soapy water and a brush to remove any dirt or grease that might be sticking to the surface.
  3. Start by sanding the plastic with a liquid sander. You can also use sandpaper, but it might be too harsh for the surface. After that, choose a primer specifically manufactured for the plastic surface. Using a primer increases the adhesion capability of plastic so that the paint and sealer sit well. Apply the primer properly and let it dry for at least half an hour.

Step Two – Apply Acrylic Paint 

  1. Before you apply the paint, make sure the plastic is completely dry. If you know how to make acrylic paint dry faster, things will be easier for you.  
  2. Touch the surface to check for the remaining primer. If it’s dried, choose your preferred acrylic paint and start applying it.
  3. Be sure to use a proper brush with large and soft bristles. Apply thin layers for fast drying and ensure even application. 
  4. When finished, place the plastic object in a well-ventilated room for drying. A hair dryer or room heater can make acrylic paint dry faster.

Step Three – Choose a Sealant 

  1. We have listed the most popular acrylic sealants for plastic surfaces. You can pick any of them depending on your needs. Acrylic clear sealant is the best option, in our opinion, as it’s specifically made for protecting acrylic paint.
  2. You need to choose the application medium as well. Sealants in aerosol spray form are the easiest to work with. Brush-on sealants are also widely available, but it will take you a long time to apply them on plastic.

Step Four – Apply the Sealant 

  1. No matter which sealant you choose, always test it on a plastic surface first. Apply a small sealant on a painted plastic and see if the paint reacts. Continue with the sealant only when it protects the paint quality and the plastic surface. 
  2. Again, make sure the paint is fully dried before applying any product. Otherwise, the paint might peel off or react with the sealer. 

[If you’re using a spray sealant, shake the canister a bit and wear your gloves and face mask.] 

Place it about 6 to 12 inches away from the plastic and spray one particular area.

3. Keep a steady hand and spread the sealant evenly on the surface. When you’re done, air dry the painted plastic and the applied sealant.

Note: As for the brush-on application, take a small amount of sealant in a bowl and thin it down if necessary.

Take a suitable brush and dip it into the sealant. Remove the excess and apply thin layers to the acrylic paint. Make sure the sealant is distributed evenly on the surface. Use a larger brush for quicker application.

Step Five – Dry and Cure the Sealant

  1. When you’ve covered the whole surface, let the sealant dry at room temperature. If needed, you can apply another layer after the first layer is dried to the touch.
  2. Typically, sealants take no more than one hour to dry. However, you should give 24 hours to fully cure the sealant on the plastic.


First, prepare the surface with a base coat and liquid sander. Apply thin layers of acrylic paint and let it dry. 

Finally, choose the right sealant and spray or brush it on the painted surface. When fully cured, it will create a glossy protective layer over the surface.

Frequently Asked Questions 

Will acrylic paint stay on plastic?

Acrylic paint might or might not stay on plastic, depending on how you’re applying the paint on the plastic surface. You must prepare the plastic by sanding its surface and applying a primer to increase adhesion. This will make acrylic paint stay on the plastic surface.

Can I use a sealer instead of a varnish?

Yes, you can use a sealer instead of a varnish to protect a painted surface. Sealers work on almost all types of surfaces including canvas, wood, plastic, and metal. They protect the paint from moisture, high temperatures, and other extreme weather conditions.

How to prevent the cracking of acrylic paint on plastic?

To prevent cracking on plastic, you must choose good quality acrylic paint specifically formulated for plastic. While applying the paint, you can add an extra binder to make the paint stick better. Apply thicker layers to slow down the drying process. Finally, add a clear coat of sealer to prevent the paint from cracking and peeling for a long time.

What kind of paint stays on plastic?

In general, oil-based paints stay longer on plastic. You can also try alkyd-based paints, as they adhere to the plastic surface pretty well. No matter what type of paint you choose, you must know how to apply paint on plastic surfaces and which products you should use for better results.

Final Words

So, now you know how to seal acrylic paint on plastic. Typically, acrylic paint doesn’t last long on plastic objects due to its water base. 

However, the paint won’t flake off if you apply a base coat of primer and finish the project by applying a sealant. 

Acrylic resin varnish, clear sealer, and Mod Podge are the best products you can get for sealing acrylic paint on any plastic surface.

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