Gluing plastic: which glue to use? How to do ?


Gluing plastic isn’t always easy: often all-purpose glue just won’t glue the plastic parts together. Still, it’s not that hard to find the right glue. If you want to glue plastic, choosing the right glue is already half the way. Here is an overview of the glues to use for gluing plastic and what to watch out for when gluing plastic. Plastic is a generic word for a myriad of different materials that surround us everywhere in everyday life. The variety of all these plastics is it, as the diversity of the glues which correspond to them must be just as much! However, do not despair of finding the right glue to glue this famous cracked or broken object back together.

What plastic do you want to glue?

If you want to be successful in bonding plastic, knowing which plastic you want to process is essential. In general, a distinction is made between thermosetting and thermoplastic plastics as well as elastomers, especially polyurethane. Premium thermosetting plastics remain dimensionally stable and strong even at high temperatures and are mostly resistant to solvents. These durable plastics such as carbon, bakelite or fiberglass can be found in the home in the form of outlets, insulation materials and kitchen surfaces.

What are the different types of glue for plastic?

It’s up to you to identify the type of plastic to find the right corresponding glue. You can rely on the number next to the recycling symbol on the item you are about to repair or re-glue.

  • The symbols 2, 4, 5 or letters mean that it is polyethylene or polypropylene.
  • The symbol 6 or the letters PS indicate that it is polystyrene.
  • The symbols 7 and 8 mean that they are ABS, in other words thermoplastic polymers.

Depending on the plastic, adapt the glue!

Strong glue

It is the most famous glue. That which is generally called super glue is known to all for its formidable effectiveness. However, it is poorly resistant to shocks, vibrations and twists and to extreme climatic conditions – the strong adhesive does not appreciate large temperature variations. It is however the most versatile glue, the one you can invest in for multi-use. However, check before purchasing that it works with the exact type of plastic you want to glue.

Epoxy glue

Epoxy glue consists of two parts: the resin one and then a hardener. It is these two elements that make this glue an extremely effective product. Use it for your DIY work or in your creative hobbies: it resists everything! To shocks, vibrations, torsions and harsh climatic conditions. Epoxy glue does not stick plastic products numbered 2,4 or 5. That is, it does not work on polypropylene or polyethylene plastic.

Neoprene glue

You can also opt for a glue such as neoprene glue. It is a glue that is suitable for hard plastic but not for soft plastic. If you want to stick hard plastic around with your kids, this is the one for you. It requires a little longer drying time than other glues.

Vinyl glue

Like neoprene glue, vinyl glue is a glue that you can use with your children. If you are planning creative hobbies combining all types of media, such as paper, cardboard, wood in addition to plastic, this is definitely the one for you.

How to glue plastic?

Below are the steps for gluing plastic. The most important is undoubtedly that of preparing the objects to be glued. These must be perfectly clean. Clean them with soap or soak them in alcohol to remove any greasy stains. Dry well. If necessary, rub them with sandpaper to facilitate the adhesion of the glue.

  • Select the type of glue that matches your plastic. Look at the instructions, they will tell you which plastic to use the product you have in your hands.
  • Follow the manufacturer’s directions for temperatures and drying times.
  • Before gluing, clean the plastic. It should be dry and free from dust and grease.
  • If your plastic is cracked, you can stop the process by placing glue at the end of the crack – it will act as a plug and stop it.
  • Press the two pieces against each other to stick, this helps to expel the air bubbles. If necessary, use rubber bands or tape to hold the two parts or both objects in place while the glue dries.
  • Read the instructions carefully to know the exposure time because the variations are large: it can range from a few minutes to 24 hours.
  • Remove excess glue immediately after gluing

For all your small crafts or creative hobbies, you can use a glue gun. It allows you to glue very small pieces of plastic together – just as it can be useful for gluing other materials like glass, metal or wood.