[NHCOLL-L:2362] Re: Insects and glue

[Doug Yanega]

Jim Druzik wrote:

>Elmer's glue is definitely not good.

and

>I have had animal glues that required enzymes for removal on
>old works of art mounted on boards.

after having said earlier:

>  >I beg to differ on your comment about water soluble gums. Polysaccharides
>>can crosslink but they are more prone to hydrolytic chain rupture which
>>increases solubility.  Since they are fully amorphous you're just not going
>  >to get insolubility.

>and Dave Furth wrote:
>
>>My experience is also with small critters and with mounting
>>techniques and glues from around the world and going back well over
>>100 years.  I have not experienced the problems Doug mentions with
>>removing specimens or parts thereof with warm/hot water or with
>  >dissecting them.

Maybe I'm a bit dense, but Dave Furth and others have been calling 
Elmer's Glue (= "white glue") and hide glue "water-soluble". When 
they said those were good, you implied they were okay, but now you're 
CLEARLY saying they're bad, which directly contradicts the earlier 
comments. So, what widely-used "water-soluble" glues were *you* 
referring to when you said above that they increased in solubility 
over time, if you weren't referring to white or hide glue?

So, let's recap:

White glue (Elmer's, etc.) = water-soluble, but BAD
Hide glue = water-soluble, but BAD
???? = water-soluble, but GOOD
PVOH = alcohol-soluble, and GOOD

Do I have that correct now?
-- 

Doug Yanega        Dept. of Entomology         Entomology Research Museum
Univ. of California - Riverside, Riverside, CA 92521
phone: (909) 787-4315 (standard disclaimer: opinions are mine, not UCR's)
              http://cache.ucr.edu/~heraty/yanega.html
   "There are some enterprises in which a careful disorderliness
         is the true method" - Herman Melville, Moby Dick, Chap. 82