Bonding Polycarbonate to EVA Foam

[kman1801]

We are making a new chinstrap for Football and Lacrosse. We have having problems using an Adhesive to bond EVA foam to Polycarbonate. About half of the cups from the first production did not pass the QC test. Each of these cracked very easily. We are using a 3M adhesive with a Petroleum Naphtha solvent. It is ideal to apply this with a brush. Is it possible that this adhesive is reacting with the polycarbonate and compromising the integrity of the shell? The cup is completely curved to mold to the shape of one's chin.

Or is it more likely the problem lies in the polycarbonate itself. I have pictures to show the result.

Please let me know your thoughts.

Keenan Glass
SportStar Athletics
keenan@sportstarusa.com

 

[TomQuinn]

Try a solvent or water based acrylic PSA. Or you could spray a hot melt PSA.

Regards,

Tom Quinn
Adherent Laboratories

http://www.adherentlabs.com