Modified cyclo-olefin thermoset

A fourth generation of electrically conductive adhesives based on cyanate esters and modified cyclo-olefin thermoset (MCOT) resins was introduced in the 1990s. These resins were specially formulated for low moisture absorption, high thermal stability, and low stress to be compatible with solder-reflow conditions. They were developed to prevent or reduce the so-called popcorn effect, a failure mode attributed... 

Modified cyclo-olefin thermosets (MCOT) for chip attachments requiring very low moisture absorption. 

Modified cyclo-olefin thermoset (MCOT) resins are liquids that cure when heated at 150 °C for a minimum of 30 minutes to form the general polymer structure shown in Figure 3.14. The monomers cure by an addition polymerization and, as such, no water or other by-products are evolved. The molecular structures are essentially nonpolar which impart very low moisture absorption properties. For two formulations developed by Johnson-Matthey, water absorptions of 0.05% were recorded when exposed to 85 °C/85% RH conditions for 168 hours. Only 0.1% water absorption was measured even after pressure cooker testing at 150 °C, 85% RH, for 168 hours. These low moisture absorption values make MCOT adhesives and molding... 

Figure 3.14 Modified cyclo-olefin thermoset (MCOT) polymer structure.

Epoxies are the most widely used adhesives in electronics assembly, followed by silicones and polyimides. The use ofthese adhesive types, along with the more specialized types such as cyanate esters, bismaleimides, and modified cyclo-olefin thermosets, is expected to increase as the total production of electronic circuits and hardware increases. In recent years, the total value of electronic components has increased tremendously from 59 billion in 1989 to an estimated 215 billion in 2003. It is predicted that the cumulative growth will be 5% to 10% per year. Adhesives for electronics... 

Electrically insulative, fast ciuitig, modified cyclo-olefin thermoset adhesive Ablebond MC723 Ablestik Laboratories 75 48 99... 

Modified cyclo-olefin thermosets for low-moisture-ab-sorbing chip attachments. 

Boron nitride and silica filled modified cyclo-olefin thermoset - - 1.0... 

Modified cyclo-olefin thermoset (MCOT) technology Low moisture absorption. Reduced popcoming. Excellent adhesion. Marginal adhesion to some substrates. 

PBGA, thermally enhanced BGA Low MOE, low stress, high thermal dissipation Epoxy blends, cyanate-ester blends, modified cyclo-olefin thermoset (MOOT), silicone materials, highly filled thermally conductive adhesives... 

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