BT-Epoxy (BT short for Bismaleimide- Triazine resin) is one of a number of thermoset

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

s used in

printed circuit board A printed circuit board (PCB), also called printed wiring board (PWB), is a Lamination, laminated sandwich structure of electrical conduction, conductive and Insulator (electricity), insulating layers, each with a pattern of traces, planes ...

s (PCBs). It is a mixture of

epoxy resin Epoxy is the family of basic components or cured end products of epoxy resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also co ...

, a common raw material for PCBs and BT resins. This is in turn a mixture of bismaleimide, which is also used as a raw material for PCBs and cyanate ester. Three cyano groups of the cyanate ester are 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

copolymer In polymer chemistry, a copolymer is a polymer derived from more than one species of monomer. The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are som ...

ize with the cyano groups to

heterocyclic A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, proper ...

6-membered aromatic ring structures with two nitrogen atoms (

pyrimidine Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The oth ...

s). The cure reaction occurs at temperatures up to , and is catalyzed by strongly basic molecules like Dabco ( diazabicyclooctane) and 4-DMAP (4-dimethylaminopyridin). Products with very high

glass transition temperature The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rub ...

s (T_g) up to 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.

References

Synthetic resins {{Polymer-stub

See also

References