| 摘要 |
<p>There is provided a novel dicyanate ester of the formula: <CHEM> wherein R1, R2, R3 and R4 are the same or different and each is hydrogen, alkyl, perfluoroalkyl, aryl or halogen; A is a bridge selected from the group consisting of direct bond, methylene optionally mono- or di-substituted by alkyl, perfluoroalkyl and/or aryl, a five or six membered cycloalkylene, sulfonyl, thio, oxy, carbonyl, phenylene, and xylylene optionally substituted by alkyl at one or both methylene carbon atoms; with the proviso that when the cyanato group is at the para-position relative to the bridge A, R1 and R2 cannot mean hydrogen simultaneously. The dicyanate ester and its prepolymer find use in the manufacture of electrical laminates having excellent dielectric properties in GHz region.</p> |
