Difference between infusion polyester and regular hand lay-up polyester?

[erikssonniklas]

Hi All

Difference between infusion polyester and regular hand lay-up polyester?

I have elaborated with vacuum infusion for some weeks now. I have just for fun infused a couple of test pieces with regular Reichhold polyester, and it has worked.

Now I wonder if I should buy special infusion polyester?

Are the difference that the infusion polyester has a lower boiling point?

Thanks in advance

Niklas

[AVMan]

In general, the only differences should be that the infusion polyester will have a lower viscosity, have a 0 thix index (no thickeners), and possibly a longer gel time. I know some infusion vinyl esters also use CHP catalysts instead of MEKP for lower peak exotherms, so some polyester might use the same. I don't think there will be any differences boiling point, as this would be due to the styrene, which both should use.

[ondarvr]

It's really just the viscosity like AVMan said and styrene content can be higher in an infusion resin because there is no atomization, so the Feds have different rules for it. The gel times, cure profiles and catalyst combinatoins can be found in both types (hand layup and infusion). The difference will be that the part will infuse much faster with less chance of trapped air. Viscosities typically range from 100 to 200 cps for infusion resins, but can be adjusted or fine tuned for each application.