[R-390] How are your knobs ?

[Robert Moses]

Do a search for 'addition co polymers from aldehydes and ketones' on
dogpile and you will find an ample offering of references. I have also
seen a bottle of 'acetone' that was quite solid. It was filled with a
white block of plastic (acetone co polymer).

On 05/17/2014 05:02 AM, Robert Moses wrote:
> This is from my training as a chemist. I cannot cite references off
> hand. I can assure you that the stuff DOES polymerize and is prone to
> leave a residue film. The standard fix by chemists is to rinse with
> distilled water while still wet with acetone. This gives a clean
> surface. Chemists use acetone to wash glassware too, but residues can
> contaminate the next experiment and produce unexpected and difficult to
> reproduce results. In the chemistry business it is common knowledge that
> aldehydes and keystones are capable of forming co-polymers of the
> addition type.
>
> On 05/16/2014 11:48 PM, Charles Steinmetz wrote:
>> Robert wrote:
>>
>>> A word on acetone: it polymerizes and leaves an organic residue.
>> Do you have references in the scientific literature that discuss this
>> polymer residue phenomenon?  My quick search didn't turn anything up. 
>> Acetone is rated as 100% volatile and is certified for residue-free
>> cleaning to a number of aerospace and military standards.
>>
>> I have never observed a residue on optics cleaned with acetone,
>> although there have been reports that it can dissolve rosin (used
>> through the mid-20th century as an inter-element cement) and deposit
>> it on the outer surfaces of a cemented-element lens.  Also, some
>> commercially available acetone has trace impurities that can remain
>> after evaporation, which has been reported by amateur astronomers in
>> connection with cleaning telescope mirrors.
>>
>> Best regards,
>>
>> Charles
>>
>>
>>
>> ______________________________________________________________
>> R-390 mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/r-390
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:R-390 at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
> R-390 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/r-390
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:R-390 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>