Epoxidized Soybean Oil

[Len]

Question about ESO in dry blend for rigid blown PVC sheet.

To get to the point I have gone back looking for changes that may have caused this problem.

One thing I have found is that about 1 year ago the product number on our soybean changed, which could just be packaging.

But the chemical formula has changed also.
Used to be C57 H26 O18
Now its C57 H76 O18

Is this something that would or could change the viscosity or temperature of the melt ?


Thank You


David

I can't tell from the chemical formulae given above. Can you tell me the supplier and grade of these two compounds? Can you provide the product data sheets for these two ESO materials. I'd like to compare oxirane content and viscosity between the two. Also, what level of ESO are you currently using in the rigid blown sheet?

I believe these epoxy plasticizers are a mixture of steric, oleic, linoleic, andlinolenic acid. So, the question, above.

Len

[Len]

David,

A couple of observations, hopefully they'll be of help and offer some guidance.

1.) the now ESO version appears to be more saturated, H76 vs H26. This might indicate the now ESO is a more stable compound, the more saturated being less likely to crosslink than the unsaturated ESO.


2.) you usage level is so low, and rightfully so in a rigid PVC, that I doubt at sl. change in chemical structure would cause a problem.

A peracid or peroxide is often used to react w/ the unsaturation in the base soya oil, creating oxirane rings, thus epoxidized soybean oil. this reaction is never complete. I'd guess that the conversion on your former product was less complete, therefore leaving more unsaturation (-c+c- bonds) in the former oil compared to the latest version.

I think you need to look elsewhere for your problem. If you doubt all this, please call Akcros and ask for Mitch Silkotch. He'll be able to help you.

Len

[Skip]

I agree with Len---check with Mitch Silkotch at Akcros. Plastoflex 2307 is a good quality classical ESO, epoxidized soybean oil.
Your first post described a formula with 50 less H atoms---that is either a misprint, or you were using unsaturated,pure, soybean oil that was not epoxidized! The Oxirane % of the older material vs. the Ackros material will tell you for sure!

0.61phr in rigid PVC is not too much---what is the rest of the stabilizer system---Ca/Zn?

As to flow lines---are you able to determine uniformity of melt temp. across the width of the sheet coming out the die?