Anybody know of a US supplier that sells “2, 4-Pentanedione”. “2, 4-P” is a VE gel time extender. This product is mixed into the resin along with the cobalt promoter, prior to catylization, to extend gel times. It’s listed in Ashland’s technical data sheets for their Derakane VE resins to extend gel times but they dont sell it, nor does Syrgis (mfr of initiators/catalysts) and I cant find anyone that does so I thought I’d pose the question to you guys. Any help appreciated!
James
Phoenix, AZ
Is this also called Acetal acetone?
Upon further research I’ve now found three substances that “could” be the 2, 4-P that is referenced in Ashland’s “Derakane Fabrication Tips” publication.
[FONT=Tahoma]1. Acetylacetone (synonym: 2, 4-Pentanedione / thanks Brad)[/FONT]
2. [FONT=Arial]Luperox® 224, 2,4-Pentanedione peroxide solution[/FONT]
[FONT=Arial]3. [FONT=Arial]2,4-Pentanedione, polymer-bound (this is comes in a powder form)[/FONT][/FONT]
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[FONT=Arial][FONT=Arial]Does anyone know which (if any) of the above is the correct 2, 4-P that Ashland references in their Derakane Fabrication Tips publication as a gel time extender. I have PDF’s of all of the material data sheets but I dont have a way to upload them here for viewing.[/FONT][/FONT]
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Here are links to the three substances mentioned above as well as the Derakane Fabrication Tips document.
Derakane Fabrication Tips - http://www.ashland.com/Ashland/Static/Documents/APM/DRKFabTipsFullVersion.pdf
I use the acetylacetone in Derakane 411-350. (from time to time)
I can’t remember the ratio for mixture but it is extremely low.
Very effective.
You need the pure stuff, in EU Akzo markets it as Promotor C.
The dosage is very low, usually as low as 0,01-0,05%
A trick to do that is mix 1% into a batch of resin, and add 1% of that mixture into the production resin. (this gives you 0,01%)
Is extending the gel time recomended?
For the final cure of the vinylester it is not important. Just takes a bit longer.
Thanks Guys! I ordered some Acetylacetone from Sigma Aldrich last Friday. It ships via overnight in a refrigirated (ice pack???) container so I’m hoping to have it tomorrow (Tuesday). Based on Herman’s comments above it looks like the proceedure is to mix the Acetylacetone into the resin prior to adding the catalyst, is this correct? Also, since this stuff ships on ice I’m curious what the shelf life is when stored in a refrigirator, anyone know?
Also, I did locate the mix ratio recommendations in Derakane’s product sheets. Looks like the recommendation is to add .04 - .07 phr depending on ambient (86-95 degrees F).
Refrigerated?
We have 25 kgs of the stuff, ambient temperature. Old but working…
Yes, add before the catalyst. And now the fun part:
-the outcome of the geltime is dependant on temperature, but also on dosage. Do a test before using the modified resin in a production environment.
-the geltime may drift somewhat in the next 24 hours or so, so what you test today, might not give the same results 24 hours later.
Anyhow, there is always a margin in which you can operate.
I like epoxy. 