questions about processing AFRPE4 prepreg 1

[relentlesspursuit]

We're working with AFRPE4 prepreg on Invar42 (700F & 200psi) & having issues with resin continuity at the surface of the tool...basically, the prepreg is leaving behind large amounts of resin flashing. Any advice?

 

[btrueblood]

Clean the tool. Apply a mold release compound.

 

[relentlesspursuit]

This has been done, we're using a typical naphta based semi-permanent mold release system; 4 applications of sealer & 2 applications of release, recoating release between parts. The issue is the prepreg outgasses amic acid, which is oxygenated. Oxygenated materials are particularly destructive to the polymers used in semi-permanent mold release systems. My hope is to gleen insight in a work around...

 

[relentlesspursuit]

wow, this is a helpful forum....

 

[patprimmer]

Choose a mould release resistant to amic acid. The prepreg manufacturer and the various mould release manufacturers should both offer technical assistance.

We do not have a team of specialists in every conceivable application sitting by just waiting to swiftly answer any question for free.

You seem to have a different use of the word flashing to my use. I suspect you use it to describe what I would call resin transfer or mould deposit.

If so btrue was correct.

Clean mould and (appropriate) mould release.

The mould surface finish and processing parameters like time, pressure and temperature may also be important.

Is this a new mould or have you moulded it without problems in the past. If it was OK but is not now what changed.

Why do I need to ask so many questions in an attempt to answer? The need to ask so many questions may indicate a reason for the lack of instant response.

The fact that this is the

http://WWW and

many of us are in different time zones may also contribute.

The fact that we all have a day job and a life means we don't always log on and read every post every day.



Regards
Pat
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[materialsliz]

Have you looked into a nickel teflon coating on your mold? It's considered a permanent mold release rather than a semi-perm that you say you are currently using.