Sciencemadness Discussion Board

Hazard Concerns: Melting FEP Fluropolymer?

MineMan - 31-10-2018 at 13:32

Hello Fellow mad scientist!

I just acquired several kilograms of FEP fluropolymer. I plan to make 1.75mm filament out of the pellets, but need some advice on the safety.

I will keep the melt temperature as low as possible and below decomposition as much as possible, but local hotspots might occur.

I will do this outside and with a fan, but unfortunately it is not an automated process and I must be near the extruder to wind the produced filament.

The main symptoms I know to watch for are headache, which I inherited a light one from just melting a few grams with a candle outside as a test...I underestimated this substance and would appreciate feedback before melting and extruding it in quantity (100grams).

If I can do this safely with your guidance I think the end product will be amazing, being able to 3D print FEP!!!

FEP melts at 250-275C and decomposes at 450C... luckily that it a large margin of safety, but I think it is more than necessary to ask the forum for advice, as I have never worked with fluropolymers before.

[Edited on 31-10-2018 by MineMan]

DrP - 1-11-2018 at 01:36

I asked similar questions a few years back when I was having to burn some things that were coated with PTFE. I was worried there might be traces of HF evolved. I spoke to the manufacturer of the polymer who confirmed that you 'could' get traces of HF liberated from F containing polymers but it was a very small amount.. They had heard of people who were experimenting with its combustion suffering from something they called polymer flu. This was basically flu like symptoms (Headaches and bad sniffles) after being exposed to the smoke from the burning PTFE.

I don't know if it is the same as FEP but I think PTFE is similar. It tends to be quite heat resistant (I mean - they use it to coat frying pans!) but can yield traces of HF when combusted.... so - if just heating gently it shouldn't be a problem, especially outside or in a fume hood... if it is going to burn then good ventilation is advised, although worse case (due to the low amounts emitted) you get polymer flu.

I hope this helps - I am not an authority on H&S of Fluoropolymers so make your own decisions but I reckon the small amount and the light melting rather than combustion should be safe enough - although I would actively avoid sniffing around the area of the melting polymer just to be safe. Even if you fully combusted it I doubt you'd get polymer flu unless you inhaled the combustion gasses directly.... although I am guessing a bit.

PS - Hi - Sorry - it's not called polymer flu (although I think some might call it that) - I looked iot up - it's called polymer fume.... I guess they call it flu because of the flu like symptoms of sore throat, aches and pains... Wiki suggest 300C as the problem temp for PTFE - I found this:

I hope this helps.

[Edited on 1-11-2018 by DrP]

VSEPR_VOID - 1-11-2018 at 04:45

Has anyone else printed this? What is your nozzle temp? Bed temp? Flow rate? Speed? Anything else?

DrP - 1-11-2018 at 04:48

Quote: Originally posted by VSEPR_VOID  
Has anyone else printed this? What is your nozzle temp? Bed temp? Flow rate? Speed? Anything else?

I think he is discussing the technical side of the polymer and printing here ( ) in his other thread. I think he opened this one up to look at the H&S aspects of hot Fluorine containing polymers. :)

Sulaiman - 1-11-2018 at 05:46

I have zero experience with fluorine compounds, but;
if I expect HCl fumes I leave ammonia solution out to evaporate first,
any HCl in the air will produce ammonium chloride smoke which is less harmful, and is visible.
I GUESS the same would work for HF ?

[Edited on 1-11-2018 by Sulaiman]

DrP - 1-11-2018 at 06:09

Quote: Originally posted by Sulaiman  

I GUESS the same would work for HF ?

[Edited on 1-11-2018 by Sulaiman]

Sounds like it should work - I have no idea either - but it sounds pretty reasonable to me. Good idea. :)

Metacelsus - 1-11-2018 at 08:46

Breathing ammonia isn't very good for you either.

DrP - 1-11-2018 at 08:51

Quote: Originally posted by Metacelsus  
Breathing ammonia isn't very good for you either.

good point - but if you know it's there you can take precautions.... got to be better than breathing HF anyway.