Composite Repair Epoxy, SikaBiresin CR72 | Perigee Direct

Product Name

SikaBiresin CR72 Epoxy Lamination and Infusion System

Brief Description

SikaBiresin CR72 is a 100 percent solids epoxy system for fabricating and repairing high-performance composite structures. The low-viscosity, UV-resistant resin supports thorough fabric wetting and air release in wet layup and resin-infusion processes, and pairs with three CH72 hardeners for a range of working times.

Popular Applications & Uses

• Marine hull and structural repair, above and below the waterline
• Wet layup on fiberglass and carbon fiber
• Resin infusion for larger or complex laminates
• Composite part fabrication and mold work
• High fiber-to-resin ratio structural laminates
• Boat building and fiberglass repair

Industries that Commonly Use It

• Marine: the UV-resistant formulation and above or below waterline suitability fit boat building and repair.
• Transportation/ Specialty Vehicle: used to laminate and repair composite transportation components.
• Aerospace/Defense: fits composite fabrication and repair where high fiber-to-resin ratio laminates matter.
• General Manufacturing: a general-purpose epoxy laminating and infusion resin for composite parts shops.

Special and Unique Features

• Three hardener speeds: CH72-1 fast, CH72-2 medium, and CH72-3 slow cover smaller repairs through larger laminates.
• UV-resistant formulation: suited to parts and repairs that will see sun exposure.
• Low mixed viscosity: approximately 350 to 650 cps for clean wet-out and reduced trapped air.

Key Properties

• Mix ratio: 100 parts resin to 18 parts hardener by weight.
• Mixed viscosity: approximately 350 to 650 cps.
• Pot life: about 30 minutes with CH72-1 fast hardener, up to about 60 minutes with CH72-3 slow hardener.
• Solids content: 100 percent, UV-resistant formulation.

Surface Compatibility

SikaBiresin CR72 bonds to common reinforcement fabrics used in composite fabrication and repair:

• Fiberglass reinforcement
• Carbon fiber reinforcement
• Glass reinforced plastic (GRP)
• Fiberglass reinforced plastic (FRP)
• Composite laminate substrates

Known backups / known substitutes

• Sika does not publish a direct cross-reference for CR72; contact Perigee Direct to compare against other laminating systems in the catalog.

Comparison Note

SikaBiresin CR72 sits alongside SikaBiresin CR94 and CR86 in Perigee's composite laminating line. CR72 adds a UV-resistant formulation for laminates that see sun exposure, CR94 favors standard wet layup and vacuum bagging, and CR86 is built for resin infusion and RTM.