| 초록 |
Vinyl-type polynorbornene has good thermal stability, high optical transparency, and low dielectric constant. However, it has low solubility, and poor mechanical and adhesive properties. In this work, norbornene dicarboxylic acid dialkylesters (alkyl = methyl 1, ethyl 2, propyl 3, butyl 4, and pentyl 5) are polymerized as a vinyl-type by Pd catalyst without cocatalyst. The polymers show good solubility in general organic solvents and good thermal stability to 350 °C. TGA experiments show an initial thermal decomposition of side chains, followed by thermal decomposition of norbornene backbone. The glass transitions (Tg) of poly-3,4,5 occur below 350 °C, as detected by DMA experiment, while they are not seen for poly-1,2 due to the onset of thermal decomposition below their Tg. Moreover, the mechanical and adhesive properties are improved by the introduction of alkylester groups. |
