Lexan bullet proof "glass" (polycarbonate)

[coastershiner]

I was recently given a sheet of lexan. This product is rated for use up to 800 degrees, and wikipedia lists the chemical resistance to alcohol and diluted acids at "good" which by their scale seems like the top. Maybe i need to be remined of rule 8. I do completely follow it, exect for this one time by mentioning a synthetic. I am expecting every one to remind me that we dont use plastics at all, so why bother with this thread?
I could cut a piece 4" around and clamp it with a triclamp, Would this be a potential viewport/cleanout on the top of my keg? Or is this an absolute no-go.

[dstaines]

From the website of Interstate Plastics, a distributor of Lexan material:

Lexan also known as Polycarbonate[emphasis is mine] is used as a glass alternative when an impact resistant material is needed. It is commonly used in three domains — building (glazing and domes), industry (machine protection and fabricated parts) and communication and signage. Some usages include space and sports helmets, clear high performance windshields and bullet resistant windows (sometimes called bulletproof glass).

It's called commonly "glass" because it's used in impact resistant windows, and there is a market aversion to "plastic" windows. But it's not glass, it's polycarbonate. As such it would absolutely not be safe to use for a view port, and definitely goes against Rule #8.

[NZChris]

You don't only get ethanol out of your still.

Check it's resistance to ethyl acetate. Also note that these resistance charts are only concerned with the resistance of the plastic to the solvent, not the effect of the plastic on your likker.

[coastershiner]

Rated d for ethyl acetate, the lowest score possible.
thanks guys I guess sometimes I just need a kick in the same direction!

[shadylane]

Washing polycarbonate with alcohol will turn it milky.
It probably wouldn't stay clear very long if used as a view port.

[coastershiner]

Just for fun, I put a 4×4 square in a litre of 95% foreshots and put it up on the shelf. I will check it in a month or something, probably get all soft and wierd. Either way, no Lexan for my kegs!

[cob]

that smell you smell when you cut that 4x4 square is what your liquor would smell/taste like. no is the very best choice.

[NZChris]

Just for fun, I put a 4×4 square in a litre of 95% foreshots and put it up on the shelf. I will check it in a month or something, probably get all soft and wierd. Either way, no Lexan for my kegs!

Also, foreshots are in contact at much higher temperatures than those used to create the resistance charts, a 10% wash boiling at around 195F, 90C.

[dstaines]

Just for fun, I put a 4×4 square in a litre of 95% foreshots and put it up on the shelf. I will check it in a month or something, probably get all soft and wierd. Either way, no Lexan for my kegs!

I'm glad you did that. If you take a few pictures it might yield some very convincing visual evidence for why we stick very strictly to Rule #8.

[Jimbo]

it will 'craze' full of micro cracks, and become very brittle. when you apply the slightest force on it it will crumble in your hand.

This happened to me with a piece of polycarbonate racking tube that I was using to draw samples out of a barrel (I know I know). Ive since bought a glass wine thief.

[coastershiner]

I will take some pics of the "glass" tonight, then in a week, then a month. I will also let the dish get quite warm to hopefully increase the destruction of the lexan. If anything looks worth sharing, I wll.

[coastershiner]

No VISIBLE change to the glass today (24 hour soak). About half of the fores evaporated tho. Gonna put it in a jar with a lid I think.
I will post a pic next week if it starts to visibly deteriorate.

[coastershiner]

[quote="Jimbo"]it will 'craze' full of micro cracks, and become very brittle. when you apply the slightest force on it it will crumble in your hand.

This sheet is 1/4" thick. I dont think it will ever crumble, but I will test it with a hammer after a month long soak.

[jb-texshine]

So what happened to the sample

[Drunk-N-Smurf]

I saw the sample when I visited coaster a couple months back. It was fine, still clear, looked brand new.

[coastershiner]

No change in the sample lexan. Looks like it did before I put it in the liquor. That is a 7 month soak in some 95% foreshots, about 4 liters. As mentioned before, the stuff is rated "A" for alcohol, so im not surprised. I have no way of testing the liquid to see if anything leeched out though. This was just an experiment to see if the lexan would get brittle like some of the polycarbonate beakers do when used with fresh high proof liquor. It did not get brittle.

[Jimbo]

hmmm, how to explain the racking cane tube that disintegrates after a couple exposures then? Its polycarb. Stuff will crumble in your hands into a thousand pieces. Any material scientists here?

[HDNB]

a hundred years ago, in shop class grade 7, we made a terrarium from "plexiglass", what i would today call lexan...maybe it is different.

we used acetone to glue the edges together, just one q-tip swipe on both surfaces and presto, instant krazy glue like bond. it held water to the top of the box like an aquarium. the edges stayed clear too, looked like a million bucks.

maybe you have no acetone in your fores? (good job on the ferment!!)

[thecroweater]

It sure would be interesting to get a sample of thoses heads tested but you would need a control sample. Tricky think about plastics is there is something like twenty thousand recognized different compounds and many variations of them. I wonder how many different polycabonates there are

[Massassi]

did you ever do a sniff/taste test to see if the alcohol had picked up a noticable flavouring from it?

[columbia36]

Plexiglas is acrylic, so not the same thing. Before I found this forum I used my acrylic test tube with my proof hydrometer. After the first test it crazed like a busted windshield. Tried it again and the alcohol ran through it like a sieve. I guess that's why we don't use plastic.