B-521 is a unique epoxy system having a dual glass transition temperature: at higher temperatures of 200°F the system cures in seconds to a rubbery state—a flexible solid. On cooling it transitions into a semi-rigid state, providing high strength with a good balance of impact and shock resistance with enough flexibility to handle thermal cycle.
B-521 offers rapid, structural stress free, curing between glass and plastic. Upon cool-down joint stresses are released to produce a structural stress and fracture free bond between dissimilar materials in minutes. Stress free potting for electronics fast cure is obtained at low temperatures suitable for electronics. Eliminates warping and fractures in assemblies. Excellent for autoclave applications of composite laminates with long pot life for assembly and cure in seconds with a flexible bond line.
Cure: 10 minutes at 170˚ F
Fast chemical cure, long pot life
Semi-flexible thixotropic two-part epoxy, off white, 10:1 ratio
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