| 초록 |
Polyimide/clay nanocomposite films were prepared from the solution of poly(amide acid) and organically modified –montmorillonites(OMMTs) using N,N-dimethylacetamide as a solvent. Poly(amide acid) was prepared from the reaction of 2,2’-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA) and 2,2’-bis(trifluoromethyl)-4,4’-diaminophenyl(TFDB). Polyimide(PI) is used largely for microelectronics. However it would be desirable to reduce the coefficient of thermal expansion (CTE), amount of moisture absorption and gas permeability, because those properties of PI are not sufficient for advanced electronics use. Montmorillonite(MMT) consists of stacked silicate sheet about 2000Å in length, 10Å in thickness. It has a low CTE and a high gas and water barrier property (MMT is dispersed homogeneously into PI matrix and oriented parallel to the film surface). Owing to this special structure of clay, the defects of PI are improved. The properties of PI/clay nanocomposite films were characterized by WAXD, UV-vis transmission spectra, thermomechanical analysis, AFM, RDA and four-point probe. As clay contents increase, PI/clay nanocomposites show better properties than pristine PI. However the transparency of the PI/clay nanocomposite films are reduced a little. |
