Myriam,
Yes, you should dry the Benzoylperoxide, but be very careful. 
Benzoylperoxide becomes explosive when dry, so please only dry small 
amounts, carefully. Air bubbles are usually introduced during the mixing 
of the resin components these can generally be removed by placing the 
resin in a vacuum chamber for a short time. Sorry but wrinkles in 
methacrylate resins go hand in hand in my experience.
Regards
JVN

Myri37@aol.com wrote:

> dear all
> do you know if it's possible and nessecary to dry benzoylperoxid before dissolving it in methylmetacrylate resin ? i heard that we must do it to avoid bubbles in embedding blocks..
> could you give me some advice to avoid these air bubbles and wrinkles in sections? 
> thanks very much in advance
> myriam baali
> 
> 
> 
> 
> 
> 


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John V Nailon
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