PLA Finishing Experiment

Hey guys, did a little experimenting with PLA and some different chemicals. I'm sure someone maybe interested in this. Included is a small write up and images.
I assume majority of these chemicals would be hard for a hobbyist to source, but this will add to the information currently available. Be safe while experimenting.
Cheers.

--Safety Warning--
The results of this experiment are for EDUCATIONAL and SCIENTIFIC purposes ONLY.
The chemicals used in this experiment are toxic and potentially dangerous if they are handled improperly. Do not attempt these experiments unless you have the proper training and equipment to handle toxic chemicals. Please refer to the MSDS(SDS) of ALL chemicals before handling.

Images: PLA Finishing Experiment
___________________
PLA Finishing Test

Experiment:
Place PLA sample into solution
Wait 5 days
Observe and remove from solutions
Measure diameter wet
Wait 4 days
Measure diameter dry


Chemicals Tested (listed from left to right in photos)
1 - Dioxane
2 - Propyl Propionate
3 - Xylene
4 - Toluene
5 - Hexane
6 - Solution w/ Trimethylpentanediol monoisobutyrate
7 - Solution w/ Diethylene Glycol Dibutyl Ether
8 - Solution w/ Terpineol, Diethylene Glycol Monoethyl Ether Acetate
9 - Methanol
10 - Texanol
11 - Diethylene Glycol Dibutyl Ether

Original Filament Diameter: 2.9-3.0mm

-Dioxane-
1 - Wet Diameter: N/A Dry Diameter: N/A
Observation: Sample completely dissolved.

-Propyl Propionate-
2 - Wet Diameter: 3.4mm Dry Diameter: 3.2mm
Observation: Removed from solution and the surface had a white powder residue that could be removed with some scraping. Very slight color loss occurred near the surface of the sample. Caused the filament to expand.

-Xylene-
3 - Wet Diameter: 3.6mm Dry Diameter: 3.3mm
Observation: Removed from solution and the surface had a white powder residue that could be removed with scraping though it was much harder to remove than the Propyl Propionate. There was also more color loss than the previous sample (Propyl Propionate). Caused the filament to expand to a higher degree.

-Toluene-
4 - Wet Diameter: 3.7mm Dry Diameter: 3.3mm
Observation: The sample was completely stripped of color. The diameter expanded the most when soaked in Toluene. Material also softened to a flexible state.

-Hexane-
5 - Wet Diameter: 3mm Dry Diameter: 3mm
Observation: No Change.

-Trimethylpentanediol Monoisobutyrate-
6 - Wet Diameter: 3mm Dry Diameter: 3mm
Observation: No Change.

-Diethylene Glycol Dibutyl Ether-
7 - Wet Diameter: 3mm Dry Diameter: 3mm
Observation: No Change.

-Terpineol, Diethylene Glycol Monoethyl Ether Acetate-
8 - Wet Diameter: 3.6mm Dry Diameter: 3.4mm
Observation: Slight color loss near the surface, filament expanded.

-Methanol-
9 - Wet Diameter: 3mm Dry Diameter: 3mm
Observation: Very minimal color loss near the surface of the filament.

-Texanol-
10 - Wet Diameter: 2.9mm Dry Diameter: 2.9mm
Observation: No Change.

-Diethylene Glycol Dibutyl Ether-
11 - Wet Diameter: 3mm Dry Diameter: 3mm
Observation: No Change.


Conclusion: Dioxane was the only solvent to completely dissolve the PLA sample. Therefore, a failed sample print was dipped in Dioxane for about 45 seconds, and the other side was buffed with a rag with dioxane. The included pictures will show the surface finishes. For the dipped side there are many inconsistencies that can be seen in the texture which is slightly rough. The buffed side of the sample has a smooth finish that could be possible for finishing. Out of the chemicals tried, Dioxane seems the safest though may not be readily available for hobbyists.


EDIT1: Safety disclosure

Edited 2 time(s). Last edit at 12/19/2013 11:44AM by williaap.

Looks like dioxane is available on Amazon for $70/2.5L. A bit expensive, but not too bad if you aren't using too much of it. Seems like it might be a good way to finish PLA parts. Does it harm ABS? If not, it could be used to dissolve PLA supports on ABS parts without having to use lye.

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It does harm ABS. I put a sample in a few minutes ago and the dioxane is already a bit cloudy from the ABS breaking down. I really like that idea but unfortunately it will not work with dioxane.

I looked up dioxane on Wikipedia ( [en.wikipedia.org] ) and looked up an MSDS for it ( [www.sciencelab.com] ). It looks like nasty stuff, worse than acetone.

Quote
Wikipedia
This compound is irritating to the eyes and respiratory tract. Exposure may cause damage to the central nervous system, liver and kidneys.[7] Accidental worker exposure to 1,4-dioxane has resulted in several deaths.[8] Dioxane is classified by the IARC as a Group 2B carcinogen: possibly carcinogenic to humans because it is a known carcinogen in other animals.

So yeah, Dioxane is carcinogenic, and prolonged exposure looks like it's generally bad for you all over. Personally I would not use such a chemical.

Edit 1: Links formatting.
Edit 2: For the sake of comparison here is an MSDS for acetone: [www.sciencelab.com]

Edited 2 time(s). Last edit at 12/18/2013 03:35PM by crispy1.

This would make a great wiki article, williaap. Would you be willing to put this on the wiki? If you do not have time for it, would you mind if someone else did?

All of this stuff is really nasty. The hazards of these chemicals are clear across the board and it is only a matter of time before somebody gets hurt trying this at home. Go ahead and tell me how I'm being a sissy. I'm used to it now as I comment on these types of posts every time I run across them. The only safe way to use some of these is in a fume hood with appropriate safety protection which I'm assuming you had access to. Recommending that others try this without getting specific about what precautions to take is negligent.

@KDog, I agree with everything you said. This stuff is dangerous, and no one should be recommending or even discussing it without making the dangers of these chemicals abundantly clear to everyone who might read the discussions. That's why I included the links to the MSDS.

KDog and cripsy1: Good grief, guys. This is Science!

williaap performed an experiment and he is reporting his results. I don't see anywhere where anyone said "I recommend you use these chemicals." There are tons of dangerous things in the forums and on the wiki - lasers, fire hazards, mains electricity, toxic chemicals, and on and on... Whenever I write something up on the wiki that is potentially dangerous, I put a clear and concise warning. Here is an example from the EDM Wiki page:

Quote
EDM Wiki page
Safety Warning

Use caution and do not attempt to build an EDM system unless you have the necessary tools and skills.

The power supplies used in electrical discharge machining can be dangerous (potentially lethal if mains electricity is not properly handled).

Experimenting with electric arcs submerged in a flammable liquid (certain dielectric fluids are flammable) presents a potential fire hazzard.

If williaap is kind enough to let us put his work on the wiki, I would recommend a simple warning along the lines of this:

Quote
Safety Warning
The chemicals used in this experiment are toxic and potentially dangerous if they are handled improperly. Do not attempt these experiments unless you have the proper training and equipment to handle toxic chemicals.

Edit: KDog and crsipy1, rereading your posts I thought I should dampen my tone so as not to come across too cavalier regarding safety. My apologies. You are correct that these chemicals are dangerous and people should be made aware of it. But we shouldn't be forbidden to discuss experiments simply because they are dangerous.

Edited 1 time(s). Last edit at 12/18/2013 06:46PM by MattMoses.

I would like to see an evaluation of cyclohexanone.
I use it on PC, and PVC, and ABS but not on PLA.
$130.00/gal on ebay

Thank you for the constructive criticism, as these are not safe chemicals to use. I will revise the post above to reflect the safety hazards of using chemicals in a non-controlled environment. As assumptions have been made, these tests were preformed in a laboratory, and under a fume hood.

I do not expect people to try this at home, but I do understand that people may have access to chemicals such as these and may not be properly informed when dealing with hazardous chemicals. This was meant for SCIENTIFIC and EDUCATIONAL purposes only. IF YOU DO NOT UNDERSTAND THE HAZARDS OF CHEMICALS YOU ARE USING PLEASE REFER TO THE MSDS!

Please bear with me as I make these revisions which may not be until tomorrow when I have time to sit down.

@MattMoses, You are right on with my intents to inform our audience. And, once this has been revised I would be happy to add this to the wiki for educational purposes.

Quote

williaap performed an experiment and he is reporting his results. I don't see anywhere where anyone said "I recommend you use these chemicals."

I don't have an issue with people experimenting with stuff, provided they are informed about what they're getting into, know the risks, and have experience and training to perform the tasks safely.

I agree the OP didn't explicitly recommend that anyone else use these chemicals. BUT, neither did he include any sort of warning that some or all of the chemicals mentioned are varying degrees of dangerous. That is the only issue I have, and the reason I wrote my first post.

Quote

There are tons of dangerous things in the forums and on the wiki - lasers, fire hazards, mains electricity, toxic chemicals, and on and on...

You're right, but in my mind there are a couple of caveats that IMO make stuff like chemicals more dangerous than say, a 2W laser. Firstly, people generally have a better understanding of the risks/dangers of something like a high power laser. It's easier to conceptualize that pointing it at flammable things or themselves has immediate bad consequences. The immediate part is important. Chemicals, especially carcinogens, have a very delayed consequence to exposure. They might use it once and think "well I'm not dead so it must not be dangerous". When in fact the consequence for exposure doesn't come until 10-20 years down the road. It's pretty well documented that people have a much harder time analyzing and thinking about risk when the consequences are removed from their immediate situation. For this reason I think substances such as potential carcinogens merit a much stronger and much more prominent warning any time their use is discussed.

Heirloom Chemistry Set
[www.kickstarter.com]

I still want to see cyclohexanone tested with PLA.

Don't get sick, as cyclohexanone is not going to be replaced any time soon for use in assembling medical devices.
I had a gut feeling that the drying times, were inadequate to remove all the cyclohexanone that dissolved into the plastic of medical devices, because I could smell it.

Cyclohexanone contamination from extracorporeal circuits impairs cardiovascular function.
CHX can reproduce clinical cardiovascular, neurological, and edema morbidities associated with extracorporeal circulatory treatment.

Cyclohexanone [CHX; C6H10(Embedded ImageO)] is an organic solvent used in the production of polyvinyl chloride (PVC) medical devices, including intravenous (IV) fluid bags and EC circuits. CHX easily migrates from PVC tubing and connections into fluids that come in contact with PVC (10, 12, 35, 37), irrespective of the type of IV fluid. CHX can leach from PVC bags and IV tubing into IV fluids in sufficient concentrations for CHX metabolites to be detected in neonatal urine samples (26). Therefore, it is likely that EC patients and patients receiving large fluid volume:patient volume quantities of IV crystalloid are at risk for significant CHX exposure, given that their full blood volumes circulate continuously through CHX-treated PVC tubing and are frequently augmented (+25% of original volume) with CHX-contaminated fluids.

[ajpheart.physiology.org]

Quote
crispy1
I agree the OP didn't explicitly recommend that anyone else use these chemicals. BUT, neither did he include any sort of warning that some or all of the chemicals mentioned are varying degrees of dangerous. That is the only issue I have, and the reason I wrote my first post.

In central europe, there are storage, handling and first aid instructions and hazards always printed on the packaging of dangerous chemicals. This not the case in US and anywhere in the world?

Did you test Dichloromethane or Tetrehydrofuran?

OMG, just assume that everything discussed will kill you unless proper precautions are taken.
Substitute the words "Deadly Poison" for every chemical mentioned in the posts above and proceed as you see fit.

If you can't figure out WHAT precautions to take then don't even consider it.

If you don't know what an MSDS is or where to find one then stick to baby safe consumer products from the market..."Safety Warning" Dont tie the shopping bag over your head there's danger from suffocation.

Geez... Can't people take responsiblity for their own safety...if your going to let other people be responsible for your safety then
your destined to shorten your genetic tree, which will be better for the rest of us.

Rant Completed!

Quote
tjb1
Did you test Dichloromethane or Tetrehydrofuran?

I am curious about dichloromethane too. Carbomorph is made by dissolving polycaprolactone in dichloromethane, mixing it with carbon black, evaporating the solvent, and then rolling the resulting residue into fibers. I would like to try making this myself, but I am hesitant because I am not quite sure what to do with all the evaporated solvent (I don't have access to a fume hood).

@A2, I do not have any cyclohexane in the lab.

@tjb1, I do not have DCM or any THF.


I agree that when dealing with any chemicals it is better to take the stance that anything can hurt or danger you so you should be well informed before handling. And I say this because unfortunately I believe the number of people that know what an MSDS is, is much lower than the amount of people that do not know what it is. But, please...if you do not know what the effects of handling a certain chemical or product are...the manufacturer has an MSDS that will tell you...There are dangers everywhere, look at like rust removers you can get from the store...Some contain HF...That is something I'd rather not want to deal with...But the information is available just have to use your head.

Quote
williaap
@A2, I do not have any cyclohexane in the lab.

@tjb1, I do not have DCM or any THF.


I agree that when dealing with any chemicals it is better to take the stance that anything can hurt or danger you so you should be well informed before handling. And I say this because unfortunately I believe the number of people that know what an MSDS is, is much lower than the amount of people that do not know what it is. But, please...if you do not know what the effects of handling a certain chemical or product are...the manufacturer has an MSDS that will tell you...There are dangers everywhere, look at like rust removers you can get from the store...Some contain HF...That is something I'd rather not want to deal with...But the information is available just have to use your head.

Well those two that I mentioned were ones I have heard that gave very similar results as compared to ABS - Acetone. I'm not equipped to deal with those type of chemicals and not sure where to source them so I didn't explore it any further. If I didn't live in an apartment I would definitely try it.