B-staged epoxy in a cookie form

Master Bond offers B-staged epoxies in easy to handle 22 or 30 gram cookies. B-stage epoxy system is formulated at elevated temperatures and poured into cookie molds to solidify. Since it is a solid, it must be heated in a forced air or convection oven at 200°F for about 30 minutes to transform it to a liquid. The working life at this temperature is 60-75 minutes. To complete the cure, the temperature should be 350°F for 2-3 hours. Liquefied but uncured material can be reused by allowing it to resolidify at room temperature. Cured material cannot reliquefy; resolidified epoxy can become liquid again. It is important to note that after dispensing the final cure can occur at a later more convenient date, even at another location.

Processing Advantages

If you need a small amount of material for your application, it is more convenient to cut out a portion from a cookie for use, then dig out the same amount from a can.

Utilization of these cookies has resulted in improved consistency, less wastage, improved productivity and cost effectiveness. Different grades can be conveniently applied evenly and uniformly for bonding multiple substrates. Application techniques include hand processes such as brushing, dipping, rollers, and spatula. Master Bond cookies have also been employed in mass high volume production because of their numerous processing advantages that optimize production efficiency. These B-staged epoxies in cookies have proven their versatility in countless aerospace, microelectronic, optical, robotic, specialty OEM usage.

Performance Properties

Master Bond B-stage systems are used mainly in potting, encapsulation and casting applications. Some salient properties of these systems are:

• Excellent toughness coupled with great resilience properties
• Good electrical insulation properties with high dielectric strength
• Excellent resistance to high temperatures and thermal cycling/shock