Molding w Flame Retardant

[Joel JS]

Hello,

Got new jobs arriving with flame retardants in the materiel, and wondering what issues or concerns that may arise because of these additives.

Thx!,
Joel

[RMihalus]

They love to plug up vents in the mold. Clean vents often and pay close attention to how often the mold will need PM.

[rickbatey]

Use caution with residence time and shear/barrel temps. FR’s are sensitive and will bloom to the surface or cause splay or early degradation of the melt. I’ve not found them to stop up vents when processed with as much care as you can. Some resins may require drying depending on agent used in resin.
Rick

[Joel JS]

Thanks for the info, will be keeping those ideas in mind.

Joel

[tommyboyfl]

1. Do not leave FR material in the barrel for extended time at full processing temp, it becomes corrosive to your machine. If pausing production, purge the barrel or at least drop temps to 120C or so.
2. We have had FR additive 'bloom' or 'plate out' on the surface of molded parts, days, weeks or even months after molding.

Here is a good article: https://www.plasticstoday.com/content/primer-molding-flame-retardant-plastics/1954701241174

[nemanja]

In my case is PA 66+GF30+FR, and best results (for my process) is to make preventive mold maintenance. Just cleaning tools on certain cycle number (depends from tool) reduced scrap rate from 10% to 2%.
And as said, never leave them in barrel. At the end of production just put PP inside and should prevent some headache at next startup. :)

BR

[Joel JS]

thx for the advice guys!.......good to know.

Joel