What is the Difference Between Vinyl Ester and Polyester Resin

The key difference between vinyl ester and polyester resin is that vinyl ester resins have a low resin viscosity, whereas polyester resin has a high resin viscosity.

There are many important applications of vinyl ester resins and polyester resins. Vinyl ester resin is used as a precursor to producing major classes of resins, in repairing materials, and laminating due to waterproof properties, and used in homebuilt airplanes, etc. while polyester resin can be used for panels that are fabricated with polyester resins and reinforced with fiberglass for restaurants, kitchens, restrooms, and other areas requiring washable low-maintenance walls.

1. Overview and Key Difference
2. What is Vinyl Ester Resin
3. What is Polyester Resin
4. Vinyl Ester vs Polyester Resin in Tabular Form
5. Summary – Vinyl Ester vs Polyester Resin

What is Vinyl Ester Resin?

Viny ester resin is a type of resin that is prepared by the esterification of an epoxy resin in the presence of acrylic or methacrylic acids. In this structure, we name “vinyl” groups as the ester substituents that are prone to polymerization. Therefore, an inhibitor is usually used when preparing the resin material. Thereafter, we can dissolve the diester product in a reactive solvent (e.g. styrene) to initiate polymerization through free radical formation formed in the presence of UV radiation or peroxides.

Vinyl Ester and Polyester Resin - Side by Side Comparison

Figure 01: A Typical Vinyl Ester Resin Structure

Viny ester resin is a thermosetting material. We can use it as an alternative to polyesters and epoxy materials. Here, we can use this material as the thermoset polymer matrix in composite materials. In these combinations, the strengths and bulk cost effectivity are significant. These properties are usually intermediate to that of polyester and epoxy materials. Further, the resin viscosity of vinyl ester resin is lower than both that of polyester and epoxy.

There are different applications of vinyl ester resins, including use as a precursor to producing major classes of resins, in repairing materials and laminating due to waterproof properties, in homebuilt airplanes, etc.

What is Polyester Resin?

Polyester resin is a type of resin formed from the reaction between dibasic organic acids and polyhydric alcohols. It is a type of synthetic resin. Generally, maleic anhydride is useful as a raw material in the presence of dibasic functionality of the unsaturated polyester resins.

Vinyl Ester vs Polyester Resin in Tabular Form

Figure 02: Isomerization of Maleate and Fumarate to Form Polyester Resin

There are polyester resins that are unsaturated. These are useful in sheet molding compounds, bulk molding compounds, and toner of laser printers. Moreover, we can use panels that are fabricated with polyester resins and reinforced with fiberglass for restaurants, kitchens, restrooms, and other areas requiring washable low-maintenance walls. In addition, this material is useful in cured-in-place pipe applications.

When considering the chemical structure of polyester resins, these are a category of polymers where the ester functional group repeats within the main chain. Furthermore, polyesters are step-growth polymers. In this polymerization process of preparing polyester resins, a difunctional acid or acyl halide reacts with difunctional alcohol.

What is the Difference Between Vinyl Ester and Polyester Resin?

Vinyl ester resin and polyester resin are important polymers. We can use these materials interchangeably because they show some similar characters in their applications. The key difference between vinyl ester and polyester resin is that vinyl ester resins have a low resin viscosity, whereas polyester resin has a high resin viscosity.

The below infographic presents the differences between vinyl ester and polyester resin in tabular form for side by side comparison.

Summary – Vinyl Ester vs Polyester Resin

Viny ester resin is a type of resin that is prepared by the esterification of an epoxy resin in the presence of acrylic or methacrylic acids. Polyester resin is a type of resin that forms from the reaction between dibasic organic acids and polyhydric alcohols. The key difference between vinyl ester and polyester resin is that vinyl ester resins have a low resin viscosity, whereas polyester resin has a high resin viscosity.