How to bond PET – Successful PET bonding
What is PET? (Polyethylene Terephthalate) – PET is a thermoplastic material. It can be difficult to bond PET with many adhesives, as a result, Permabond developed specialty adhesives to allow bonding PET without pre-treating. PET is easy to recyclable so it is commonly used as disposable packaging. The recycling symbol is 1 inside the triangle. Some PET is glass filled or mineral filled.
How to Bond PET?
In addition to adhesion to PET, several other parameters are generally involved in selecting the best adhesive. Understanding the solvent and temperature resistance of the adhesives is especially relevant in selecting the best type of product.
Permabond TA4610 bonds PET that is untreated. For the highest bond strength without pre-treatment, these structural acrylics would be the first choice. Similar products with faster and slower set times are also available. Permabond TA4610 is a structural acrylic adhesive, therefore it provides good resistance to polar solvents and very good resistance to non-polar solvents.
All Permabond cyanoacrylate adhesives bond PET when Permabond POP primer is used first. Permabond 105 and 2050 provide the highest strength. Cyanoacrylates are often desired due to the fast set times, however, they provide poor resistance to polar solvents. They do provide good resistance to non-polar solvents.
The temperature resistance of both the TA4610 and cyanoacrylates exceed the temperature resistance of PET.
Tips for surface preparation and bonding:
For untreated PET there are several options.
- Bond as received with Permabond TA4605 or TA4610
- Prime with Permabond POP and use a cyanoacrylate adhesive. Note that POP only increases adhesive when using a cyanoacrylate, therefore it won’t increase adhesion of other adhesive types.
- Flame, corona or plasma treat the PET surface. After treatment, most adhesives types will provide some adhesion.
Properties of PET
- Surface energy: 44mJ/m²
- Maximum service temperature: 70°C
- Melting temperature: 250°C
- Packaging, plastic bottles
- Woven materials such as sailcloth
- Disposable medical devices
- Films and wraps
To determine the best specific adhesive to bond PET in your application, please provide some detail to our technical team and our adhesive advisors will get back to you with a recommendation.