[NSRCA-discussion] Micoballons

[Bob Richards]

I'm not a chemist, so what I am about to say is just an educated guess. :-)
   
  Epoxy gets warm as it cures, and cures quicker as it gets warm. A thick mass of epoxy will cure quicker than a thin film since there is less surface area through which the heat can escape.
   
  Microballons are hollow glass spheres, and probably act as a thermal insulator. This insulation property is possibly preventing the heat of the curing process from escaping, and causes the epoxy to cure quicker in the center since the heat can't escape.
   
  Try using longer curing epoxy. :-)
   
  Bob R.
   
  
Glenn Hatfield <randy10926 at comtekmail.com> wrote:
      
I recently used micro-ballons in an epoxy for the first time.  I was really surised how much the cure time changed with just a small ratio of micro-ballons.   I was able to feel the expoxy warming up in the mixing cup.  As an experiment I mix a small batch and tried to go for the max ratio; but ended up with a hot spot in the middle that set before I could finish the mixing.
   
  This stuff appears to be acting as a catalyst; which really surprised me.  What is really going on here.
   
  randy


_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20060417/ebd8e20b/attachment.html