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Does Benzidine polymerize in presence of alcohol?

  1. Sep 23, 2014 #1

    jim hardy

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    This is a hobbyist question, i hope you'll entertain it.

    Have a laugh on me, guys. One of my psychological quirks is i just hate to see a nice piece of machinery junked. I try to rescue too many of them. Runs in the family, my Grandmother rescued stray dogs.

    ....I found my laser level has lost the fluid from one of its little bubble leveling vials.
    http://www.geier-bluhm.com/images/3-0505.JPG [Broken]
    So i drilled a tiny hole in one end and flushed it with rubbing alcohol, 91% isopropyl delivered through an insulin syringe.
    Next i mixed some really old green fabric dye with isopropyl and filled the vial. I sealed the end with hobbyist epoxy, JB weld.
    Looked great, i was so proud of myself.
    Well- the next evening that dye was thick as honey . Looking into what went wrong i noticed the JBweld site says "clean the surfaces. Do not use alcohol."
    Uh oh - I figured the alcohol must've been a solvent for the epoxy before it set up.
    So i got the old stuff out , refilled the vial and sealed it this time with hot glue, first testing to make sure alcohol didn't soften the hot glue.
    Again it set up but this time after two days. It went to a gel that wouldn't flush with isopropyl.
    So i figured maybe denatured alcohol would work better to flush it.
    Well ! Denatured immediately turned it into a white gooey paste, consistency of nearly dry white paint.

    Using the home handyman's philosophy of "Get a bigger hammer" i found my stash of acetone.
    Acetone got the goop out but the acrylic vial cracked and fell apart.

    Well, just to find the error of my ways i researched vintage Putnam brand dyes and found they're probably Benzidine based and as we speak are being outlawed for their carcinogenic proclivity..

    Searching on 'Benzidine polymer alcohol' took me to a lot of chemistry articles for which i simply lack vocabulary..
    And a patent for automotive paint pigment.

    Did i re-invent Nylon or something?

    To conclude this sad story : I've found replacement vials for 75 cents plus eleven dollars shipping. Or i can get a whole new laser level on sale at Sears for $32.
    It is difficult to turn loose of eleven bucks to ship a 75 cent item.
    But the same outfit makes this beautiful machinist's level......it'd really dilute that shipping cost.

    http://www.geier-bluhm.com/images/004.JPG [Broken]

    Ahhh, 'tis a fine madness !

    Hope this post doesn't lower the PF standards too much. I was curious what happened....
    Feel free to move to general discussion thread...

    old jim
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Sep 28, 2014 #2


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    You have a very complicated organics collection there. I can't help with the polymerisation of benzedrine, but I had assumed that the green / yellow colour was ethylene glycol (= antifreeze) in denatured ethanol / isopropyl. But actually Fluorescein seems to be used as the colouring. The fluid in some cheap bubble levels now becomes clear when exposed to sunlight, maybe they are glycol based? That loss of colour also happens to the colouring in some dish washing detergents.

    There may be some advantage in experimenting with blends of Absinthe or Chartreuse. The bubbles for levels are still available from the usual suppliers.
  4. Sep 28, 2014 #3

    jim hardy

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    Thanks Baluncore.. i'm no chemist.

    Someplace i have a tiny little jar of Florescein .
    But, i need a 25 X 10 mm bubble tube now. Will surely run across one someplace.
    Next time i'd use Easter egg dye.
    thanks, old jim
  5. Sep 28, 2014 #4


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    I don't think it a quirk. You're just being an engineer. :D But it does run in the family, from my experience. ;)

    When I try to restore something and make it worse, there's usually a lot of WTFs. I do talk to inanimate objects. :L

    Having this "psychological quirk" means you'll pay the $11 shipping cost. After all, the rescue is precious. :cool:
    Last edited: Sep 28, 2014
  6. Sep 28, 2014 #5


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    Hey Jim, I'm just a bit concerned that you are willing to spend hours of labor on a ten cent device. I'd send a bottle of wine or a six of beer if you prefer in hopes that you will find it more useful than the bubble level, but the lady at the post office told me it costs $11 for shipping. :L

    Did you know you can turn your smart phone into a bubble level? There's an app for that...
  7. Sep 28, 2014 #6

    jim hardy

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    Uh-oh i'm found out.... will probably buy a $75 machinst's level to calibrate the 75 cent plastic one, too ....

    Hmmm ..... would that involve a computer ? ... well, considering my signature line ......
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