BT-Epoxy (where BT stands for
bismaleimide triazine
Triazines are a class of nitrogen-containing heterocycles. The parent molecules' molecular formula is . They exist in three isomeric forms, 1,3,5-triazines being common.
Structure
The triazines have planar six-membered benzene-like ring but ...
, its chemical components) is one of a number of thermoset
resin
In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on n ...
s used in
printed circuit boards (PCBs). It is a mixture of
epoxy resin, a common raw material for PCBs and BT resins. BT stands for Bismaleimide-Triazine resin. This is in turn a mixture of bismaleimide, which is also used as a raw material for PCBs and
cyanate ester
In chemistry, cyanate esters are chemical substances in which the hydrogen atom of the phenolic OH group is substituted by a cyanide group (). The resulting product with a cyanate group is termed a cyanate ester. Cyanate esters based on a bis ...
. Three cyano groups of the cyanate ester are trimer (chemistry), trimerized to a triazine ring structure, hence the T in the name. In presence of a bismaleimide, the double bond of the maleimide group can copolymerize with the cyano groups to heterocyclic 6-membered aromatic ring structures with two nitrogen atoms (pyrimidines). The cure reaction occurs at temperatures up to 250 degrees C, and is catalyzed by strongly basic molecules like Dabco (diazabicyclooctane) and 4-DMAP (4-dimethylaminopyridin). Products with very high glass transition temperatures (T
g)- up to 300 degrees C - and very low dielectric constant can be obtained. These properties make these materials very attractive for use in PCBs, which are often subjected to such conditions.
Applications of Epoxy
Epoxy resin coatings have long been used in marine, construction, and industrial environments for the high level of protection they provide as a final coating. They have increasingly been used by craftspeople and artists according to the Chicago Tribune (citation ?). Epoxy flooring is valued in warehouses, and in the food industry. It is versatile and comes in a variety of colors.
Synthetic resins
References
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