Working with foam? It's not the easiest substrate, but luckily here at Hotmelt.com we have lots of adhesives and solutions for even the most difficult foam bonding applications. Let's start with the basics.
Common Issues When Bonding Foam
Melting. Foam is a sensitive substrate and hot melt is, well, hot.
Open Time. When covering large surfaces, having your adhesive set too quickly or not fast enough can cause major issues.
The Bond. Not James, the act of actually marrying your two substrates. Foam is very porous which can lead to a smaller percentage of the surface actually making contact with the substrate you are mounting it to.
Solutions to Common Issues
Melting. Melting is probably the most common problem especially when working with polystyrene and EPS foam. There are two great ways to combat melting your foam products.
First, use a low temperature hot melt. These tend to run 100-150 Degrees cooler than standard temp products which can be the difference between a successful bond and a melted mess. 3M has a very good low temp glue gun option in the Polygun LT with Quadrack which pairs well with their 3792LM hot melt, excellent for bonding foam.
Second, try a spray hot melt. These systems can be a little more expensive than a simple bead/extrusion gun and stick but they can cover significantly more surface area and apply at much cooler temperatures.
The TEC 6300 and TEC 7300 are excellent applicators for this and the TEC 420, 425 and 430 are great spray hot melts, each offering a longer open time than the next giving you the ability to time your bond perfectly.
Open Time. Trying to put two substrates together after hot melt has already begun to set will result in a significantly weaker bond. The spray adhesive's we have already discussed are one very popular solution to this problem. Another is using a variable temperature glue gun.
A variable temperature glue gun like the Surebonder PRO2-220 or the PAM HB 220 allow you to adjust the temperature of the gun. Raising the temperature will make the glue dispense at a higher temperature extending your open time while lowering the temperature will do the opposite.
Try and find the happy medium between open time and keeping your foam from melting. Surebonder 725 is an excellent foam bonding adhesive because it dispenses well at both low and high temperatures. Try it for your next foam bonding application.
Common Foam Bonding Applications
- Athletic Mats
- Equipment Cases
- Custom Freight Assembly
- Foam Brushes
Need more volume?
Bulk Applicators for Foam. High volume foam applications have the same issues but require a higher output solution. Enter the LS10 bulk hot melt system. This is an all electric bulk hot melt tank with variable temperature. This system is highly customizable to adapt to just about any adhesive foam bonding need.
Bulk Hot Melt for Foam
The FoamPack is an excellent bulk hot melt for bonding foam. It offers a fast, aggressive tack to make sure your surfaces stay stuck.
Common Types of Foam
Here is a list of common foam types that can be bonded using some type of hot melt solution.
Open Cell Foam Types:
- Nitrile Vinyl
- Lo-perm Polyether
- Cross linked Polyethylene
Closed Cell Foam Types
- Filter Foam
- Hi-density Urethane
- Urethane Film/Foam Laminate
- Polyester Film/Foam Laminate
You are now an adhesive foam bonding wizard, congratulations on your new found knowledge. If you have any additional questions or need help picking out the perfect product, please contact one of our adhesive engineers to discuss your application further.