Vinyl Ester and Epoxy Resin
Vinyl Ester Resin
Vinyl ester resins and polyester resins are very close in molecular composition. The molecular chain is longer in Vinyl ester resin. This helps it absorb impact better than polyester and it shrinks less. There is also less chance of de-lamination when using VE resin. Vinyl ester can be used as a final coat after polyester resin to create a better water barrier.
Vinyl Ester resin is also more resistant to solvents and water degradation. It is typically used in gas tanks, boat hulls and other items that will be exposed to chemicals or water for extended periods of time.
VE resin is a tougher resin because of its longer molecular chains. It can withstand repeated bending better than both polyester and epoxy resin. Vinyl ester resin cures with a tack.
Regarding costs, vinyl ester resin is more expensive than polyester resin, but cheaper than epoxy resin. The hardener/catalyst for vinyl ester resin and polyester resins is MEKP.
Epoxy resin is an ideal resin for high performance and light weight parts. It is water resistant. It can be used with carbon fiber, Kevlar and fiberglass cloth. It is not compatible with chopped strand mat (fiberglass mat). It has great bonding capability and has a fast wet out. Epoxies have a low odor compared to other resins. One of the only downsides to epoxy is that it is more expensive than polyester and vinyl ester resin.
Epoxy resin comes in two parts. The resin side is typically designated as the 'A' side. The 'B' side is typically the hardener side. Our epoxy comes in either a 2:1 or 4:1 ratio. There is a choice of three different hardeners: fast, medium and slow. Which speed of hardener chosen depends on the temperature, the desired working time and drying time. Epoxies dry with a full surface cure.
We carry the 1200 Series and 1300 Series ProGlas epoxy. The biggest difference between the two is the 1200 Series is UV stable, extremely clear, tough and high gloss. It is UV resistant which reduces yellowing and surface degradation from UV exposure.
It is ideal to work in temperatures around 77 degrees. Resin will typically not cure well in temperatures below sixty degrees and will cure too fast in temperatures above 90 degrees.
Mixing the correct ratio of A:B is extremely important. Most problems that occur with improper cure is due to not measuring the correct ratio or not mixing completely the two components.
Liquid Properties of Systems
|Speed of hardener||Slow/Flexible|
|Mix ratio, Resin to Hardener by volume|
|Viscosity, cps mixed|
|Gel time, minutes at 77 degrees F.|
|Set time, hours at 77 degrees F.|
|Recoat time, hours|
|Recommended minimum working temperature ( degrees F)|
|Suggested uses: F=Fairing, L=Laminating, A=Adhesive|
Cured Properties of System
|Heat Deflection Temperature (HDT) Note: higher HDT's attainable with post cure.|
|Flexural Strength, Psi|
|Tensile Strength, Psi|
|Flexural Modulus, Psi|
|Tensile Modulus, Psi|