Vinyl Ester Over Epoxy

In areas that must be able to flex and strain with the fibers without micro fracturing epoxy resins offer much greater capability.

Vinyl ester over epoxy.

Epoxy vinyl ester resins ver are an important class of high performance thermoset molding resins. They are produced by the addition of α β unsaturated carboxylic acids to epoxy resins. It adds excellent strength rigidity adhesion water and chemical resistance. Vinylester is essentially a styrene modified epoxy resin.

Cured epoxy tends to be very resistant to moisture absorption. For vinylester resins and even less for polyesters. Before coating a fully cured layer of epoxy with polyester gelcoat prepare the surface properly to remove any amine blush. Has some great papers on this which i am quoting from.

The two main types of epoxy resins are bisphenol a diglycidyl ether dgeba and epoxy phenol novolac epn. In the case where a part originally manufactured utilizing polyester or vinylester has yielded to strain and cracked a well reinforced epoxy repair will tenaciously hold to the substrate with 2000 psi strength vinylester. Wash away amine blush with water and an abrasive pad such as a 3m 7447 hand pad. Using epoxy you can improve the laminate properties with a post cure almost always.

To cover wood a laminate using epoxy resin and 10 oz cloth will yield a much better job than 10 oz. Epoxy adheres to wood much better than polyester does. The hardener catalyst for vinyl ester resin and polyester resins is mekp. Regarding costs vinyl ester resin is more expensive than polyester resin but cheaper than epoxy resin.

Vinyl ester resins are produced by the reaction esterification between an epoxy resin and an unsaturated monocarboxylic acid. It is water resistant. Many high strain repair areas and lightweight parts must flex and strain without micro fracturing. Quality epoxy resins stick to other materials with 2 000 p s i.

Cloth and polyester resin. Specifically proper cure of vinyl ester resins and a 15 year study of the effective use of permeation barriers in marine composites to prevent corrosion and blistering. Vinyl esters also use peroxides e g. Before applying gelcoat over epoxy.