I resolved not to ask any questions until I'd read every question on here, for fear of boring everyone with the same old questions that you've already answered a million times, but needs must, and I'm sure that I'm showing myself up as a real novice here.
I made a polyurethane resin (biresin g26) mold, and the attached documents show the two ingredients up as being pretty damn nasty, especially component B. Once I poured B into A, there was still residue in B, and, unthinkingly, I poured some water into it. Then after I used up the mixed resin, I poured the water from B into the residue of A.
Some of the two mixed in the pot, and there's some formed resin I can throw away, but there's also still a couple of blobs of part B in there, and a load of water. I know I'm not meant to pour that down the sink. It's classed as hazardous waste. I'm also kind of freaked out at some of the things it claims it can do (dangerous to inhale, proven carcinogenic??) Anyway, I've thrown the resin bit away, and I bottled up the water. I mean it's 99% water and 1% residue but I still don't want to pour it away. And what about the pots, and stirring tool, and brush I used to get rid of air bubbles, etc. I don't want to bin that stuff each time (and I'm not sure whether it's safe to bin, or if it's hazardous?) but I can't wash it if I don't pour it down the sink, and I don't want that stuff just lying around the flat.
And I see videos of people just pouring it out without wearing gloves or anything, totally chilled, and it doesn't seem to tally with the scary ass info sheet!! Am I totally overreacting here? (wouldn't be the first time!)
I promise I'll have more interesting questions in future...
Hi David. Generally what you try to do with this sort of stuff is to mix it, so what you throw away is in a non-reactive state. Adding water to it is not a great idea as you found out, as it is not water-soluble.
Use nitrile gloves for protection, and invest in a digital kitchen scale (wrap it in clinging to protect it.) Yes, you will throw stuff away, but remember you have paid for it! You will get better at estimating amounts. Use newspaper to wrap waste. Hoard yoghurt pots for mixing. If you use a stainless spatula, you can wipe or crack waste off it.
You may be able to evaporate the water to purify it. Leave it in a wide tray, away from any animals, and in a warm place. Then wipe away anything left with kitchen towel and dispose. But I appreciate this may not be practical.
Finally, the health hazard warnings spell out the worst case scenario. Take sensible precautions and you should be ok. (I have seen people describe how they allowed epoxy resin to get in their hair, and wonder how they got an allergic reaction...!) Most medicines seem to have death as a possible side effect....
This is chemistry we're talking about. Try to take reasonable precautions.
I'm 51 and I've been an artist and modelmaker since I was a pre-teen. I've probably inhaled and ingested enough paint, carcinogens, vapors, and heavy metals to keep my corpse inviolate for a hundred years...but I don't do it anymore.
Anytime you are working with plastics, resins, and mold making materials, wear a respirator. Get a good one with replaceable cartridges and change the cartridges. The guys in the professional shops have to use them - often by union rules and local regulations, and there's good reason.
Disposal of hazardous waste is going to be different depending on your locale. Aside from Simon's great suggestion of only using what you need, you need to find out what the local regulations are, and deal with it accordingly.
Pouring it down the drain or chucking it in the bin is probably prohibited. Sure, you might not get caught, but if you intend on doing this stuff repeatedly, it's better to find the waste disposal facility in your area that handles it, and pay the fee. A fine for improper disposal will almost certainly be higher.
Yes, the resin I have contains isocyanates, which is cyanide, although I understand it is not in a volatile state. I reckon if you use only small quantities and have plenty of ventilation, that goes a long way. A fan behind you blowing the fumes away from you is also good. Sure, a respirator is ideal, but the cartridges are time-limited and not cheap. The pros use them because they are exposed for 40 hours a week.
This is not to suggest one should be blasé about safety. It is a matter of assessing the risk and taking appropriate action. I worked with a couple of tonnes of epoxy resin over several years, and went through several thousand disposable nitrile gloves. I have not had any allergic reaction, but I know of others who are sensitised to the stuff. I sometimes changed gloves 5 times a day!
I used a lot of dust masks for sanding, and respirators when I was painting with polyurethane paints. I did not even contemplate spraying as that creates a severe hazard for which you need a compressed air helmet. And I made a decision to sand (my boat) by hand because that raised less dust than using electric sanders (which also clogged up quickly).
Horses for courses. I like plaster for moulds, because it is relatively benign (dust hazard only), and the waste is easily disposed of.
thanks guys, this is great advice. :-)