How Much Internal Release Agent Should I Mix Into The Resin For Testing?

The amount of internal release agent added is measured considering parts per 100 of resin, by weight (phr). This is based on unprepared (pure) resin. For example, adding 1.0 phr of internal release agent means that one part of internal release agent is added to 100 parts of pure resin.

The amount of internal release agent varies depending on the resin formulation. The type of resin, concentration of fillers and pigments, and molding geometry can affect the amount of internal release agent required.

Generally, a typical polyester pultruded material may use 0.25–2.0 phr of internal release agent while an epoxy pultruded material may use 1.0–3.0 phr. It is generally recommended to start at a higher level for testing and reduce to lower levels to optimize at production time.

Chem-Trend has carried out extensive testing in its laboratories and established relevant thresholds and ranges for each of its in-house release agents. See the product data sheet for suggested additive levels for each Chemlease® product.