Talk Composites - The Forum for Advanced Composites

choice of resin for making carbon fiber prepreg

http://www.talkcomposites.com/Topic6109.aspx

By liu - 5/16/2013 10:27:02 AM

May I know what kind of resin is suitable for making carbon fiber prepreg. i want to make  prepreg by myself, i but not sure what resin can be use and the ratio too.

many thanks,

Liu
By mawgan - 8/17/2013 5:53:16 PM

You can use any resin system for making pre-preg although there are a few things that you need to consider:

- Depending on the resin system and hardener you use your working times will be the same as it would be doing a normal wet lay up so an ultra slow hardener would be the best choice.

- You will need a freezer to store it until it is to be used and once thawed the working times will be dependant on the resin system and hardener that you use.

- As already stated, you will need to weigh your cloth and impregnate the correct amount of resin accordingly, UD carbon and e-glass fabrics will be on the lower end, around 35% but woven carbon should be up around 42%.

- Once resin has been impregnated it will need to be rolled up on a suitable backing as the material will more than likely stick to itself and it will ease the application.

- Most commercially made pre-pregs use toughened epoxy systems which are much stronger than wet layup systems, however, these resins have very high viscosity at normal temperatures so they need to be impregnated with heat and pressure by machine.

Overall, commercially made pre-pregs have resin systems designed to have good outlife at room temperature (usually between 30-60 days) and are designed to be cured at specific temperatures and ramp rates. So unless you have an advanced understanding of resin systems, resin formulations and cure curves for different applications and systems it is not really worth doing.