Need help with toughening of Exp. Polystyrene

Hello
Does Anyone on here know how to toughen up eps? The goal is to toughen about 10-15 mm of a shaped eps Surfboard blank. Its goal is to both spread loads better as well as to bond the eps beads together. The beads tend to let go of each other very easily as local point loads are applied to the nth over time. The solution must bond to epoxy, and would preferably use epoxy as well. How to rubberize epoxy? Use of nano particles? The solution should also be white, or clear/see through.
As the Surfboard will receive vacuumed nylon and s-2 glass over the EPS, the structure should be very tough yet flexible. The foil and fibres are supposed to accept the spreaded loads.
Any insights to more profound knowledge is welcome too, as I am a hack!
Cheers, Wouter

At my school there is a surfboard making class; people of all skills make boards. The boards I see made are just eps with glass layed up over it. Epoxy resin. Never seen anyone try to do what you’re saying, though I can understand what you mean. I haven’t heard of my surfer friends having that issue with any boards they’ve made. Could it be an issue with the foam? Are you trying to do this so you can vacuum it?

But if you really want to make a stronger and more rigid board… You can cut through the foam in places, either length or width wise, and then layup glass between the pieces to create a spar box type setup. Though I doubt that you want a board that rigid?

Not sure if I’m going the right direction? Maybe you’re only talking beefing up a small section for local reinforcement?

Use an adhesive film or even a prepreg?

Like this…

Check out this video on YouTube:

http://youtu.be/cFaBRS9NNNo

Done like this

Check out this video on YouTube:

http://youtu.be/qBr5IzK4U8o

It’s EPS so pre preg is out of the question…

and those videos… not sure what to think about that… one is an infusion video, which is good and mostly makes sense. Except that you can’t pull full vacuum on eps or it’ll crush right?

The other with the 3D glassing? Not sure what they meant by that… they don’t really explain the process at all. ANd the guy who cut out a piece of a board is like flicking it to test how strong it is? hahha But after he melts out the core, there is some layer? Can’t really see what the whole deal is about. Seemed like maybe they just infuse and the resin fills in the surface of the porous foam?

I think the 3d flashing is the result of infusing over eps the resin works into gaps in the eps.

Yah that’s what I was thinking as well… just using the porous nature of open cell foam right? They act like they created some new invention or something in the video…

3d glass is more something like this in my book

I agree sammy.
Basically just the infusion process gives it a bit better penetration. It does create a pretty good bond compared to just normal lay up on a board , gives a solid feel to the top layer , just go easy on the vacuum I guess.
I defiantly wouldn’t call it 3d glassing

Tim