Polyurethane resin repurpose

Hey guys,
I saw a thread regarding sterling products vs awlGrip in which jimbo1490 gave a detailed response. It inspired me to join and reach out to your collective minds.
I am looking to stabilize carbonized sandstone, limestone and ironstone with resin/ protective sealer.
I believe I am looking for a ( cost effective) water clear, very low viscosity polyurethane that is stable and wont yellow. The solution must set very hard to then be able to be worked to a high gloss ' glass like finish' for stones.
Currently I carbonize sugar within the pores of my base stone materials to pronounce any colour refraction from precious opal impregnated within the stones( sugar, sulphuric acid, heat)(oil, heat)(sugar, oils, burn, heat).
I am also looking to see if there may be an alternative process we could come up with that can darken the host rock without losing any light refraction. Then seal and polish to glass like finish ( biggest problem is sandstone).
I am looking forward to any suggestions.
Regards,
Mike

 

Is this for a business or a hobby of yours?

 

Hi gonzo,
It's my hobby for now. Am looking to test a small manufacturing process though if I can improve my current process and the numbers work.
Wont be a big thing but have a cpl tonnes of rocks I could process.

 

Clears that stay clear long term are tough to come by. Is the finished item an indoor or outdoor product.

Indoor is a bit easier.

How thick is the clear portion that you will be looking through?

 

I know of no polyurethane that will not yellow. If you find one, please let me know.

 

Mike welcome to the club.

I would try a two part automotive clear acrilic over coat.
As Eric hinted at urathanes yellow.
Most water bourn paints are relatively soft, and don't polish to a super high sheen.

Paul

 

If you are looking at manufacturing, the materials need to be tested properly. Start with a design of experiment. That will set the testing parameters and methods. Keep good records; of everything. Once you have all the data, it is time to analyze it. For example, compare hardness to clarity of the coating.

 

The process I am looking for is to stabilize stone for jewellry and other manufactured pieces of which semi precious stone can be used.
Eg. Spheres, slabs, cabochons, freeform shapes, beads, bowls, etc
So the answer would be both indoor and outdoor I guess.
The 'coating thickness' will be minimal as the process will be under vacuum to draw the resin into the stone to provide a balanced cutting surface on porous material which you cant high polish without.

 

So we sampled some monocompontent, 2 part epoxy and cyanoacrylates but they either didnt get the polish we are looking for or they yellow.
It was suggested to look at sterling marine grade products. I came across the thread sterling vs awl on here which was interesting.
Do you think a 2 part clear acrylic be able to vacuum into the stone? Or would this process require a resin process first then acrylic overcoat?

 

Well, as we know, there is such a thing as vitreous china, a similar process probably what you should be looking at to "glaze" your stone. Glass won't turn yellow, that's for sure. Ondarvr would know far better than me, but the other thing that came to mind, clear gelcoat, even clear tooling gelcoat, if such be obtainable. But I doubt any organic clear material, will hold up to UV light indefinitely.

 

I'm not sure how vacuum processing will increase the penitration..

CA is my go to if absolute clarity is desired. If it doesn't meet your requirements, then I don't have another suggestion.

Good luck

 

Get a sample of 904-061

Duratec SDS’s & TDS’s | Duratec http://duratec1.com/duratec/?page_id=590

 

Polyester is pretty good, vinylester may be a bit better for UV, I don't know. Firing with a glaze as Mr Efficiency said, is the most permanent, I think.

 

VE has very poor UV resistance.

Also, VE base resins tend to be very dark in color, so VE clears look dirty.

 

So here's a left field question.
Would sodium silicate do the job?