| 초록 |
For the manufacturing of the high temperature organophillic layered silicates(OLS), we have choose the poly(amic acid) as swelling agent. Poly(amic acid) have some advantages such as simplification for synthesis, alteration of chemical structures or compatibility with polyimide based matrix, and so on. Firstly, we synthesized two series of poly(amic acid)s having various molecular weight by adjusting the molar ratio of initial polyimidization condition and confirmed their molecular weight and chemical structures by NMR technique. Secondly, we prepared the polyimide(PI)/OLS nanocomposite films from solution blends of the precursor PAA and the OLS using doctor blade coater followed by thermal imidization. And last, The casted films, containing 1∼9% by weight of OLS, were characterized by means of TGA, TEM, XRD and AFM to investigate their thermal properties and morphologies. As a result, the nanocomposite films were exfoliated up to 9wt.% of OLS. And also thermal stability and tensile modulus became higher as increasing content of OLS.
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