Selecting Resin and Hardener

The first step to success with any epoxy project is correctly selecting resin and hardener to suit your project, processes, and working temperature. Entropy Resins offers several biobased epoxy systems designed for laminating, coating, clear coating, and hot coating; casting and clear casting; and compression molding. These epoxy resins are matched with hardeners that control cure speed. The following guide will help you choose the best resin and hardener combination for your epoxy project.

LAMINATING & COATING

SUPER SAP CLR, BRT, ONE

For laminating and coating, choose CLR Clear Laminating Resin, BRT Optically Brightened Laminating Resin, or ONE High-Biobased Laminating Resin.

There are three Entropy Resin systems we recommend for fiberglass lamination and thin coatings at room temperature: BRT, CLR, and ONE with their corresponding hardeners. The resin and hardener you select will be based on whether you are laminating glass cloth, applying a clear coat or seal coat, or hot coating. Ideal working temperature with all hardeners is 70°F – 85°F.

CASTING

SUPER SAP CCR

For a clear casting project like this colorful pyramid, choose CCR - Clear Casting Resin.

Select CCR Clear Casting Epoxy thick coatings (greater than 1/4”) or for casting. CCR has two compatible hardeners, CCF Fast Hardener and CCS Slow Hardener, that vary the cure speed. We recommend CCS for larger casting thicknesses/volumes and CCF for smaller volumes.

• CCR’s low color and low viscosity allow for bubble-free, crystal-clear castings. It’s ideal for art and hobby applications such as jewelry, river tables, and other casting or embedding projects.
• Has UV stabilized additives to resist yellowing which is desirable for artistic applications. Add a UV stable topcoat over fully cured epoxy for longterm color stability.
• There are two hardeners to select from based on the speed and thickness/volume of your application: CCF and CCS.
• Ideal working temperature with all hardeners is 60°F – 80°F.

COMPRESSION MOLDING

SUPER SAP CCR

For compression molding, which is popular among ski and skateboard makers, choose CPM.

CPM is a compression molding epoxy system for fast cycle times in heat-assisted molding processes of fiber-reinforced composites. The CPM system delivers a high bio-content, excellent fiber wetting qualities, and thixotropic characteristics to limit sag in high-temperature cure applications. A high modulus combined with excellent elongation properties enable durable yet lightweight composite parts. CMP is a USDA Certified Biopreferred® Product with 30% biobased content.

• There are two hardeners to select from based on speed: CPF (fast) and CPS (slow).
• CPM uses elevated temperatures to reach full cure quickly. This allows the epoxy to reach ultimate properties with short cycle times. While CPM can be mixed and applied at room temperature, it requires an elevated minimum cure temperature of 150°F (65°C). When paired with CPF Fast Hardener, an elevated cure temperature of minutes at 180ºF (82˚C) is required for 20 minutes to cure to full properties. When paired with CPF Slow Hardener, an elevated temperature of  180ºF (82˚C) is required for 40 minutes to cure to full properties.

Interested in learning more about Entropy Resins, click here to learn more about the benefits of using eco-friendly resins on your next DIY Surfboard project.