Talk Composites - The Forum for Advanced Composites

Working with Phenolic Glass Prepreg (Hand Lay-up) - Aeronautic Industry

http://www.talkcomposites.com/Topic6477.aspx

By Vicotex - 6/13/2013 3:29:34 PM

Dear all,

I would like to know if someone can provide me information (not MSDS, I already have it) regarding the use of phenolic glass prepreg. Do you know any kind of manual or work-book with good practices, protection equipment (like the kind of gloves) or other type of information when working with this material? I'm preparing a document/specification but since it will be the first time working with this kind of material, I would appreciate – if possible - your help in this issue. I'm trying to reunite the best amount of information I can.

 

Beyond the material safety issue I've got some more important questions related with this phenolic glass prepreg material:

 

1) 

Problem found:

Extreme difficulty in taking out one of the protective foils from the phenolic prepreg.

 

Problem description:

After normal defreeze and plies cutting, we found out that is extremely difficult taking out the blue foil from the phenolic prepreg. We have the green foil side and this one is ok but the blue foil had the following behavior (as we can see in the photo-sequence below) which make it very hard to lay up, almost impossible. This prepreg behavior doesn’t seem us normal, so we questioned the manufacturer who replied saying that "Phenolic prepreg can be very tacky and due to raw material, the tack can vary from tack to extremely tacky. Some customers are peeling the foil at low temperature (freezer or cold room)."

 

Does anyone already face this type of situation?

 

Figure 1

Green protective foil taking out easily

 

Figure 2

Blue protective foil

 

Figure 3

Blue protective foil extreme difficulty to be taken out

 

Figure 4

Blue protective foil continuously difficulty to be taken out and starting to deform the fibers and integrity of the prepreg

 

2)

Another situation is that due to the high tack, gloves (latex) are trapped in prepreg, completely glued. How do I avoid this?

 

3)
I've heard of ice spray to facilitate the removal of foils. Do you know any application of it in prepreg's?

 

4)

To clean up the molds (metal), beyond MEK or acetone, do you know or advise some other product(s) to clean the phenolic waste?

 

 

Thank you all in advance!

Rui V.

By Vicotex - 6/17/2013 11:00:56 AM

Hello!

Because we have one sticky side, it seems a good idea to first take out the blue foil (in cold temperature) and lay-up with the other foil (green) in. Then, after all the necessary maneuvers, take out the "easy" green foil. Then, next ply, same procedure. Maybe it will help! The parts are not very complex but have some radius and angles. Let's see if it works despite the challenge that will be the sticky side in the back of the last layer!

 

Thank you carboncactus!