Epoxy resins, who to believe?

[jacquesmm]

New epoxy.

Not ours but somebody on the web is advertising a "new" epoxy resin that is supposedly safer, clearer and has some quasi magic properties.
As the vendor of two brands of quality epoxy, we must correct those extreme statements.

They make a big deal about Bisphenol A but Bis A type resins are not the nasty stuff that is being portrayed.
When Bis A type resin are manufactured, BPA is completely reacted, therefore it is not the health concern being portrayed.
They claim it to be a Novolac type epoxy resins but Novolacs are very thick and expensive. There is likely only a small amount in the formulation due to cost and viscosity restrictions. This leaves Bisphenol A and F type resin to make up the lion’s share of the volume.
Possible allergic reactions from the hardener are just as possible with that resin, it is no safer than our resins. In fact, that resin uses very similar raw materials to what we use.

See the MSDS for that resin: it is the same than ours:
"Hazard Statement(s): H317 Prolonged exposure may cause an allergic skin reaction."
and
"Sensitization: Can cause skin and respiratory sensitization"
and
"Hardener: Modified Amine Adduct: CAS# Mixture >90%"
(not Novolac . . and see notes below: the amine hardeners appear to be the most potent sensitisers)

All epoxies should be handled with gloves, grinding done with masks and some people will have an allergic reaction including to that"new' resin.

The claim about UV absorbents is exaggerated. Even with UV absorbents, that resin is not suitable as a clear topcoat. The Florida sun will make quick work of it without a suitable UV protective topcoat.

We don't know what the physical properties of the cured product is but the samples we tested cured very slowly and never attained the hardness of our resins.
Viscosity is listed on their data sheet as 3,300 cps, ours are about 700! That's OK for glue but not to wet glass.

There are some good resins out there but if something sounds too good to be true . . . you know the rest.

Do not risk your complete project by using an unknown resin. Use MarinEpoxy or Silver Tip, they are used since more than 15 years to build boats with proven performance and they don't cost more.
-----------------
Links:
The Mayo clinic about BPA;
http://www.mayoclinic.org/healthy-lifes ... q-20058331
That article is about food containers. We don't eat our resins and the BPA is completely reacted, inert.

http://www.dermnetnz.org/dermatitis/epoxy-allergy.html

http://www.westsystem.com/ss/health-eff ... -to-epoxy/

[Southern Gent]

Thank You, You always offer Professional Clear answers and advice

[OneWayTraffic]

In NZ we can get WEST 5:1 (made by a local company under licence) and some local brands (4:1) 'marine epoxy'.
The non WEST is about 25% cheaper.
I was thinking about ordering a small quantity of the other brand to test it against WEST. What kind of tests would you be doing?

[THE WALRUS]

What is the difference between silver tip and general use epoxy from System Three.

[joe2700]

What is the difference between silver tip and general use epoxy from System Three.

Haven't used their general use epoxy just silvertip but in theory the silver tip is lower viscosity(easier to wet out with), blush free, stronger, and more heat resistant. Low viscosity and blush free are important to me in boat building, slightly stronger and more heat resistant not so much.

You can download the technical data sheet for each on their website to compare properties, many of the others are almost identical.
https://www.systemthree.com/pages/techn ... sheets-tds