Adhesives for Polystyrene

What Is Polystyrene?

Polystyrene (PS), sometimes referred to as just styrene, is a thermoplastic polymer made from the styrene monomer. Polystyrene can take several forms, including foam, film, or plastic. It is designated with recycling code 6.

Polystyrene plastic is a rigid plastic that is transparent, moderately strong, and brittle. Polystyrene is also lightweight, has a low shrink rate, is easy to mold, and offers good electrical insulation. Common applications for polystyrene plastic include:

• Food packaging
• Construction insulation
• Medical equipment
• Electronics

Considerations for Bonding Polystyrene Plastic

Polystyrene plastic can be bonded through solvent welding as well as with adhesives. While there are several adhesives for polystyrene and it's relatively easy to bond, there are a few notable considerations.

One consideration when using glues on polystyrene plastic is its lower surface energy. While it does not have as low a surface energy as polyethylene and polypropylene, it has a lower surface energy than PVC or PET plastic. This lower surface energy can make it more challenging for some adhesives to wet out for strong and lasting bonds. For this reason, choosing the right adhesive and performing proper surface preparation is imperative.

Polystyrene can also be sensitive to solvents. While cleaning may not be necessary for all adhesives, mild cleaners like isopropanol should be used. Avoid acetone and other strong solvents that could damage or deform the material.

Polystyrene plastic can also be prone to stress cracking over time. Be mindful of the adhesive cure process and try to avoid long dwell times. You may also want to consider adding a stop or control into the joint to minimize the potential for stress cracking.

While these products are trusted and reliable, the best adhesive for polystyrene will be dependent on the specific application. If you have questions about what adhesive is best for your application, you can speak with our team.

While these products are trusted and reliable, the best adhesive for polystyrene will be dependent on the specific application. If you have questions about what adhesive is best for your application, you can speak with our team.

Types of Glue for Polystyrene Plastic

Because it is relatively easy to bond, there are several polystyrene glues you can use. Some common types of glue for polystyrene plastic include:

• Cyanoacrylate Glues- Fast cure times but lower strength
• Epoxy Glues- High shear strength and chemical resistance but limited flexibility
• MMA Adhesives- Less surface preparation required and faster cure times but lower strength than epoxy
• Two-Part Polyurethane Adhesives- High amount of flexibility and impact resistance but solvents may damage the surface

Of course, the exact bonding capabilities will vary from product to product, and what is a great choice for one application may not work for another application. You should always review the product's technical datasheet to see if it is compatible with your bonding requirements and test it.

How to Bond Polystyrene Plastic

Polystyrene plastic may have a lower surface energy and is sensitive to solvents, but it is still relatively easy to glue polystyrene to polystyrene or another material when you take the right steps.

Surface preparation varies from one adhesive to another with some requiring more steps than others. It is usually recommended that polystyrene plastic is cleaned and degreased before the adhesive is applied. Because it can be sensitive to solvents, you should use isopropanol or another milder solvent for this step.

The next recommended step is often to gently abrade the surface with grit blasting or sanding. This abrasion makes it easier for the adhesive to wet out the surface. After abrasion, the surfaces should be cleaned once more to remove contaminants left behind. Leave the materials to dry completely before the adhesive is applied.

When bonding dissimilar substrates, you need to ensure that the adhesive is not only suited to the environmental bonding requirements but also that it is compatible with both materials. Testing the adhesive is often the recommended best practice before committing to the product.

Cure times vary widely from product to product, so always follow the manufacturer's recommendations for best results. You should also be mindful of the suggested safety procedures associated with the adhesive you are using.

Find the Best Adhesive for Your Needs

The best adhesive for polystyrene will be largely dependent on the application. If you are unsure which polystyrene adhesive to use, we want to help. Our team has worked with various applications involving polystyrene plastic and can provide you with a personalized product recommendation. You can try samples of these products and test them on your application.