Polyethylene adhesive has been hard to come by until recently. Now, Permabond has adhesives for polyethylene that don’t require a primer or other costly surface treatment.
Polyethylene is a lightweight thermoplastic. It is often abbreviated to LDPE (low density polyethylene) or HDPE (high density polyethylene). Bonding polyethylene is considered very difficult. And as a result, it is often used as packaging for adhesive materials because the glue won’t stick to it!
It is a widely used and popular material for items such as packaging, storage containers, chemical drums, tanks, and many other low-cost assemblies. The material is not particularly high performance and will deform and melt at high temperatures and be easily attacked by solvents. This makes solvent welding, ultrasonic or infrared welding, or induction heating a good method of bonding polyethylene (to itself). However, suppose you need to bond it to a different type of plastic or substrate, such as wood, metal, rubber, or some kind of composite. In that case, it is necessary to look to some other joining method, such as industrial adhesive bonding.
Polyethylene has a low surface energy, so it is a fairly non-stick surface. There are several options for surface preparation and industrial adhesive choice that could yield high bond strengths:
These methods of treatment prior to bonding polyethylene involve high capital expenditure, space for equipment, high running and energy costs, as well as specialist knowledge for correct operation. However, once you treat the surface, you can use a wide variety of different industrial adhesive products when bonding polyethylene. Consider the costs of the investment when compared to the number of parts manufactured.
If the budget is too restrictive, or you prefer a one-step bonding process you can bypass the expensive process of preparing the polyethylene before bonding.
Permabond offers POP Primer for use with cyanoacrylate industrial adhesive. Apply POP to the Polyethylene, and the cyanoacrylate to the other part. The adhesive cures in seconds after you join the parts. Cure the adhesive by joining the parts. If you need more time to apply and assemble or wish to spread the adhesive or fill any gap, then consider Permabond TA4610 structural acrylic adhesive. This is a 2 component 1:1 mix ratio adhesive which is available in cartridges with mixing nozzles or in bulk for high speed production lines. This industrial adhesive offers excellent adhesion to untreated LDPE and HDPE. The expanded line of polyethylene adhesives includes products with faster set, low odor, and minimal gap fill.
For more information on bonding polyethylene with industrial adhesive, please contact us.
