Epoxy Equivalent Weights

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#1

Hi Guys

Wondering if anyone can help me math :stuck_out_tongue:

If I have epoxy resin with the EPW 180-190 grams, and a hardener that is 43 g/eq.

How much hardener do I have to use? I looked it up online, but I just wasn’t getting it. I ended up with a headache. I’m aware it’s simple, but for some reason I just can’t get it.

For every 185g (approx.) you need 43g/eq? Is that the way it works? So if I made 100KG, I’d need 23.24KG hardener?

Is there more to this? Are all g/eq equal? They they all use the same measurement prefixes, just vary in terminology?

Cheers
Mitchell

#2

What does it say on the data sheet or can, no instructions?

#3

This isn’t a off the shelf epoxy resin. I work for a fibreglass company, and I get to tinker with base resins and such in my leisure time.

So this part A epoxy doesn’t have a set hardener. You create your own. I’m just trying to understand how to do the maths for it.

So there’s a certain amount of epoxy groups per weight. Let’s say for every 100g is 1 epoxy group. If I want to cure it, I might need to use 40g of an amine hardener. That 40g would be equivalent to one epoxy group.

#4

http://dowac.custhelp.com/app/answers/detail/a_id/4151/~/dow-epoxy—calculation-of-stoichiometric-ratios

Dow have a good user guide laying out the theory and how to do the calculations.

#5

In this case that means the ratio is 100:40
to mix any amount just pour resin on the scale , multiply the weight number by 1.4 and that will give your the total ,
fill in the rest of the weight with hardener
example
resin 124gr times 1.4 = 173.6 total

I think