elevated cure schedules
The Resin Research Epoxy Systems can be used effectively with simple room temperature cure or as an elevated temperature system providing for very high quality, structurally superior composites. Elevated cure cycles give this system higher Tg and HDT through higher crosslink density. Superior to room temperature curing this also gives the best toughness to modulus ratios.
All our systems are based on very new epoxy/cycloaliphatic resin/hardener technology which gives better adhesion and inter-laminate wetting characteristics within the individual fabric fiber bundles. This provides for high strength to weight composites with superior heat stability, excellent resistance to fatigue along with excellent toughness and moisture exclusion properties. Through this chemistry and the effective technique of post curing, the ability of composites to withstand cyclic loading in harsh environments is enhanced.
Because of the nature of this system, the processing of the Resin Research Epoxy materials matrix allows for broad range of techniques. The myriad of resins and hardeners available allow for numerous qualities to be obtained through a materials selection with many processing choices. This allows for all processes including wet lay up, contact molding, vacuum bagging, infusion, etc. to be fine tuned to exacting standard of quality where cycle times can be maximized.
Typically most shops B-Stage. In other words let the composite gel at room temperature and then add heat to finish the cure. The advantage to this is that nothing will likely move during the elevated cure. It also can reduce the chance of print through.
Below are examples of B-Stage elevated cure schedules for Resin Research Systems.
|All Composite Pro + Project 21 Resins + Fast Hardeners to cure||3 hrs @ 72°F||3 hrs @ 110°F or 1 hr @ 180°F|
|All Composite Pro + Project 21 Resins + Slow Hardeners to cure||6 hrs @ 72°F||4 hrs @ 110°F or 1.5 hrs @ 180°F|
|All Composite Pro + Project 21 Resins + Xtra Slow Hardeners to cure||16 hrs @ 80°F||8 hrs @ 110°F or 2 hrs @ 180°F|
Direct curing the resin from a wet state is also possible. This provides for very fast cycle times and can be used in many open and closed mold processes. Below are examples of direct elevated temperature curing schedules.
Direct Cure Schedule
|All Composite Pro + Project 21 Resins + Fast Hardeners to cure||4 hrs @ 110°F or 2 hrs @ 140°F or 1 hr @ 180°F|
|All Composite Pro + Project 21 Resins + Slow Hardeners to cure||5 hrs @ 110°F or 2.5 hrs @ 140°F or 1 hr @ 180°F|
|All Composite Pro + Project 21 Resins + Xtra Slow Hardeners to cure||8 hrs @ 110°F or 3 hrs @ 140°F or 1.5 hrs @ 180°F|
The Resin Research Pre-preg System is a bit different than most prepress. This system will cure at room temperature but is extremely slow at doing so. This gives plenty of time (approx. 4’6 hrs. for PPX and 8 to 12 hrs. for PPU) to impregnate your fabrics either on a wet out table or using an impregnator and get them into a freezer. The fact that these will cure at room temperature ensures that no mater what might happen you’ll still have a finished product at the end. Generally pre-preg is direct cured mostly under vacuum but regardless of whether it’s vacuumed of open mold these cure schedules below are applicable.
Direct Cure Schedule
|Pre-preg Resin with Hardener PPX||8 hrs @ 110°F or 3 hrs @ 140°F or 1.5 hrs @ 180°F|
|Pre-preg Resin with Hardener PPU||12 hrs @ 110°F or 4 hrs @ 140°F or 2 hrs @ 180°F|