DCPD resins are a type of unsaturated polyester resins broadly used for making composite components. These resins incorporate Dicyclopentadiene, besides the “regular ingredients” like maleic anhydride, phthalic anhydride, and glycols (e.g. monopropylene glycol, monoethylene glycol, dipropylene glycol). The benefit of using DCPD is the ability to reduce resin viscosity and/ or reduce the amount of styrene in comparison to commonly used Ortho resins. This typically translates into better fiber wetting and increased loading capability for inorganic fillers. In addition, DCPD resins feature lower resin shrinkage, leading to better surface quality (smoothness, gloss) of molded components.

In the manufacturing process at Aliancys, these ingredients are combined into an unsaturated polyester chain through a poly-condensation reaction, and then diluted with a reactive monomer (in most cases styrene) and other ingredients to make a finished resin. Our customers combine the resin with specific peroxides, so a chemical reaction is initiated between resin backbone and the styrene, transforming the liquid into a hard and durable material.

The special curing profile of DCPD resins ensures the level of cure in the final part is very high, even for gel times of several hours. Also, surfaces cured in contact with air will cure tack free.  

Because of their versatility in performance and ease of processing, DCPD resins are used in Hand lay-up, Spray-up, Vacuum infusion, RTM, Casting, and Pultrusion processes. Consequently, DCPD resins are broadly used in Marine(boatbuilding), Transportation (truck components, vans, caravans), Wind (nacelles), Building & Infrastructure (bridges, profiles, façade panels,).



Aliancys has a broad range of products based on DCPD resin chemistry in its portfolio sold under the Synolite™ brand name. In order to find the best product for your application, please check out the Product Selector on this web site. You can contact an Aliancys Technical Service representative for helping you in this process (inquiry.world@aliancys.com).



For additional information, please check out case studies on Nautivela (sailing boats) and on FiberCore (composite lock gates).

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    AOC Aliancys

    AOC Aliancys

    AOC Aliancys is the leading global supplier of polyester and vinyl ester resins, gelcoats and specialty materials used for the composites industry. With strong capabilities around the world in manufacturing and science, we deliver unrivaled quality, service and reliability for today, and are creating innovative solutions for tomorrow. Together with our customers, we are shaping the future of composites with new technology and applications. Visit our websites below to learn more about how AOC Aliancys can help your business be more successful.