What are epoxy fumes made of?

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birdwatcher

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I assume from the lack of bubbles and the ability to glue laminates together that the fumes are simply the vapors of the liquids and not the product of the reaction. Am I correct? Do both product and reactants give off fumes, or just one or two?

What chemical is the fumes?

How dangerous are the fumes if I'm working indoors for 3 hours and try to keep the pot covered while applying with a stick?

What temperature does the product have to be to reach a full cure? My plan is to mix and apply and let cure at ambient temperature, which might be outdoors at as low as 60 degrees at least during application.

Is it safe to store a laminate in a bedroom to let it fully cure over night, after it was applied outdoors?

Thanks.
 
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Epoxy is a term for a pretty broad range of chemical compounds. To fully answer your health related question you need to get a copy of the MSDS sheet for the particular epoxy system you plan to use and read it carefully. If you don't understand any of the MSDS fully you need to contact the manufacturer or a qualified person for an explanation. The manufacturer will also be able to supply specifications for cure times at different temperatures which vary depending on how much and/or what hardener was used.

In general the common retail systems are not going to be a cause for concern if the exposure is of limited duration and there is adequate ventilation - UNLESS you are one of the many that are sensitive to the chemicals in the system. Since you don't yet know if you are one of the sensitive ones you have to assume assume that you are and avoid any exposure until you have gained some experience. This means at a minimum the use of gloves, long sleeves, and a respirator rated for the material being used.
 

DesertFlier

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Hot Wings has you pointed in the right direction. Check the MSDS for the specific system you will be using and obey the PPE guidelines it gives you.

I'd just like to point out that at my workplace we use primarily 3M 282 epoxy, and as long as there is adequate ventilation, no respiratory equipment is required. However, cutting and grinding the cured parts is actually much more dangerous. Once those little bits of fibers enter your lungs, they are stuck there forever. In the case of carbon, prolonged exposure over years can cause a variant of Black Lung Disease, just like coal miners used to get. Also, other chemicals used in the building process can have fumes much worse than the epoxies. Cyanoacrylate (super glue) is nasty stuff, as are some releases such as Frekote. Again, read the cans, and read the MSDS for more info.
 

DesertFlier

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As for your other questions regarding curing: again, it depends on the resin system you're using. 60 degrees sounds too cold for most systems. Read the directions supplied by the manufacturer and follow them precisely. They will usually specify a minimum temperature for curing. If it's not warm enough in your workspace, you can build a heater box around the part, which can be as simple as a cardboard box lined with foil with a small space heater inside.
 

wsimpso1

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Stored out-of-doors? Epoxy breaks down in sunlight. It takes years to destroy it completely, but the epoxy is changing for the worse from the first day. Yep. So no extended sun until it has a paint on it that is 100% proof against UV penetration. The various polymers in the epoxy (and polyester and vinylester) will all be damaged by UV over time. So, if it is not inside a building, then wrap it securely in black visqueen.

Most commercial epoxies will not trip at 60F, but an overnight at 70F will get most of the job done if it can sit afterwards without load or being distorted. My parts sit in the molds until am ready to do subsequent bonding.

Billski
 

Mac790

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...and as long as there is adequate ventilation, no respiratory equipment is required.
Personally I always wear proper equipment, even if resin producers "claim" that it's not required.


However, cutting and grinding the cured parts is actually much more dangerous. Once those little bits of fibers enter your lungs, they are stuck there forever.
Here you touched the biggest issue. It seems that you know, what you are talking about. People talks about some fumes (use proper respiratory system, proper ventilation, and infusion ideally), and it's seems that they don't know what the REAL dangerous might be.

About 2-3 months ago I was going to create a thread here "composites vs cancer, is it really safe?" But I must say that I'm very "happy" now, that I didn't. About that time one of our member was personally fighting with cancer (not lung one), we didn't know about it. And probably it wouldn't be easy for him to respond to it, for obvious reasons. I haven't seen much point in creating such thread now, but because it seems that you work for the industry and probably have some first hand experience, i would like to hear a little bit more, especially if you have something interesting to say about it. Especially if it's based on experience rather than, what we could find in the Internet, "I've heard, someone told me, or I've read an article".

I did some personal research on the topic (I spoke also with people, that work in the industry for years), but unfortunately internet is full of BS, different claims mostly without any papers on it, etc. About one thing I have to disagree with you. You wrote, that if those things get into lungs, they are stuck there forever. I would like to see/hear what is your source on it? The biggest problem about fibers is related to it size. In short some are more dangerous than others, and the worst are actually those thin and long ones. Of course it's also depend from fibbers type. As we have two main category, insulation fibers (we really don't talk about them here), and special purpose ones. Those special purpose one are much more dangerous, not only because their size, but because they are more durable, than those used for insulation.

Here is the best paper that I've seen on the topic, based on the more than 200 references, from the past 20+ years, I would recommend reading it, to any one who is actually going to work with composites. Personally I'm really tired of watching all those guys at youtube or other forums (mostly aviation related), which are sanding composites parts without any protection at all.

http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/GlassWoolFibers.pdf

But despite, it's the best paper that I've seen, still there are more questions about it than answers, the result of fibers exposure for animals are clear, but those for human not really, some of them are even contrary. And the problem is that I don't expect anyone, to make a proper research on the topic in the near future, because only marginal part of our community work with those fibers, and to be honest nobody really cares about them.

So my message is, if you really have to cut/sand it etc. Wear the best equipment that you can get.


Seb
 
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SVSUSteve

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Most commercial epoxies will not trip at 60F, but an overnight at 70F will get most of the job done if it can sit afterwards without load or being distorted. My parts sit in the molds until am ready to do subsequent bonding

By 'subsequent bonding', is it safe to assume you are referring to something like joining parts of a spar or halves of a fuselage or are you simply referring to adding additional plies to a section? How warm do you keep the storage area? Would refrigerating the area (or at least reducing the storage temperature to the range of 40 F, etc) improve things?
 

Detego

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Epoxy Allergic Reaction

The“hardener” causes many of the reaction you suspect from epoxy. All epoxy hardener can be neutralized by rinsing-off with "white vinegar",
which changes the chemical structure to a water-soluble-compound. Next, cleanse the skin by washing with warm soap and water.


Since were talking allergic reaction(s), two prime sources for these reactions could come from the powder found in some gloves, and in the use
of latex gloves themselves.


(Note:"amines" used in epoxy hardeners will pass through latex gloves)
 

Aircar

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There is another thread on health matters with composites but I can't link to it offhand. -- it is possible to 'starve' mixed epoxy of the amine hardener during cure if hot air is applied to an open lay up Amines are like smelling salts and much more aromatic and volatile than the base resin and probably account for the perceived fumes --some resins are very sensitizing (allergenic ?) --I can vouch for the Rutapox as one and tetra amine epoxies were withdrawn due to cancer fears in the 80s (they gave lower viscosity and better wet out than diamines )

I heard from a former co worker at Schempp Hirth that one of our old friends there has lung problems ('der Geier' was his nickname ) it doesn't surprise me given the amount of sanding with angle grinders and very poor ventilation or suction . I myself have sarcoidosis which causes granulomas in the lungs and while of unknown origin is suspected to be associated with dusts and inhaled irritants -- glass fibre is very likely involved . At one time I scanned for articles about sarcoid and came across a thread of sufferers including an English glider repairer who had sarcoid in his heart as well . Asbestosis is well known as well as mesothelioma --you could buy bags of blue asbestos from fiberglass suppliers to mix as "bog' or flock for joining -until at least ten years ago.... best not to tempt fate by not using breathing protection.

Pyrolized epoxy is also bad news -- overheating or burning creates some really nasty compounds (of cured resin )
 

wsimpso1

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Subsequent bonding means just what it says. In some cases, the subsequent bonding was when I included the layup in a bigger part - spar caps in a spar, multiple layups to build the doors and roof, spar in a foam tail section. In others, the following operations were structural adhesive to attach two pieces together.

Billski
 

birdwatcher

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I'm not doing any sanding. I'm just laminating epoxy on wood. Mixing, spreading, and sticking, with gloves on. I just would think if I can smell the vapors, what would stop them from sticking inside the lungs? If I open my window, it will let lots of cold air in. Yes, I could cover the parts.

I am also cutting carbon fiber with a hobby knife. I highly doubt I will inhale a splinter, though I have got some very mean splinters in my toes and hands. Way worse than wood.

The bottle does not warn against inhalation or flammability. It only says it is a skin irritant and to keep it out of my eyes. It is tower hobbies brand 30 minute epoxy.

I'm tempted to route a cardboard tunnel out my window and put a fan on the inside to suck the fumes out, but that would pull in my roommate's cigarette smoke from the hallway. The other option is working outdoors. I'd like to use candles to heat the air, but I wonder if the fumes are more flammable than the label lets on.
 

JamesG

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Just like in years before, you never know what they are going to discover is a toxin/carcinogen eventually. And when they do, it'll be too late. Discretion is the better part of valor. Tyvek suits, gloves, and a respirator don't cost that much or take that long to put on.
 

StarJar

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One aspect I'm always careful with is picking the cloth up. I always try to have it folded, in a smaller dimension, otherwise all the edges throw multitudes of slivers into the air. If it's folded and you move the piece slowly, this can be greatly reduced.
I like Topaz's idea about wet sanding.
I would not keep a recently made part in my living spaces or bedroom. Somehow I remember doing that, and having a rash in the morning (However I used the early Vari Eze epoxies, and I'm sensitized.)
 

SVSUSteve

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Subsequent bonding means just what it says. In some cases, the subsequent bonding was when I included the layup in a bigger part - spar caps in a spar, multiple layups to build the doors and roof, spar in a foam tail section. In others, the following operations were structural adhesive to attach two pieces together.

Billski

Thanks. I just was wanting to make sure I was trying to play off the same sheet of music since I am going to have a lot of subsequent bonding in my own design. In fact, I need to pick your brain through some PMs about some of the particulars for my construction processes.
 

birdwatcher

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Where is a good place to get respirators? Do I need an air tank, or is there a filter that is guaranteed to absorb all organic vapors? I would think with all the meth cooks out there that it would be hard to get a respirator for epoxy.


All my carbon fiber is already impregnated from the factory. Is that still an inhalation hazard?
 

birdwatcher

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Lowes has a $29 mask for pesticides and paint fumes. I wonder if that would work for epoxy fumes. The specification is insultingly uninformative. They just want us to buy any old mask and not know how long it is good for or what exactly it is good for. No link to replacement cartridges either.
 

bmcj

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Just like in years before, you never know what they are going to discover is a toxin/carcinogen eventually. And when they do, it'll be too late. Discretion is the better part of valor. Tyvek suits, gloves, and a respirator don't cost that much or take that long to put on.


...until they decide that Tyvek is a carcinogen.
 

birdwatcher

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...until they decide that Tyvek is a carcinogen.

I shopped for respirators at home depot. The cartridges are $17 a pair, and my friend who does hazmat says the home depot ones are the cheapest there are but only last an hour. I think it depends how thick the fumes are, but even then they are too expensive for me considering I doubt the fumes will be that bad.

Still, I have to wonder if anything comes out of the filter into the air when sucking air through the filter. I think the filter is good in moderate fumes, but maybe counter productive at low enough levels. I'm just going to cut open my window and turn on the ceiling fan a bit.
 

DesertFlier

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I shopped for respirators at home depot. The cartridges are $17 a pair, and my friend who does hazmat says the home depot ones are the cheapest there are but only last an hour. I think it depends how thick the fumes are, but even then they are too expensive for me considering I doubt the fumes will be that bad.

Still, I have to wonder if anything comes out of the filter into the air when sucking air through the filter. I think the filter is good in moderate fumes, but maybe counter productive at low enough levels. I'm just going to cut open my window and turn on the ceiling fan a bit.

I think your logic is on the right track here. The 3M cartridges we use at work cost 11 bucks a pair, and they last about 10 hours. Even with the longer life, it's a bit too pricey unless you have a known allergy.

That said, there shouldn't be anything but good clean air coming through the respirator if it's fitted properly to the wearer and has the correct cartridge installed.

At work, our Environmental Health & Safety Department does air quality studies. According to them, the organic compounds in the air while mixing and applying resin are below the Permissible Exposure Limits. The only way you would get an overdose is if you had your nose right over the cup.
 
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