초록 |
The properties of polyurethane can be modified by dispersing inorganic and organic fillers in polyurethane matrix. The PU/clay nanocomposites for coating applications were studied. Pristine montmorillonite was treated with several kinds of organifiers by cation exchange reaction. Polyurethane/clay nanocomposites were synthesized by in-situ polymerization method. The equivalent weight ratio of the nanocomposite components are 2.52:1:1.5 for MDI:PEA:1,4-BD. The organoclay was sonicated in DMF(10min) for better dispersibility and added into the mixture of the reactants. The reaction was carried out at 65oC for 5h under nitrogen atmosphere and the final concentration of the reaction mixture was 20wt% in DMF. The morphology, thermal and mechanical properties of the nanocomposite having the various content (0.5wt%, 1wt% and 3wt%) of organoclay was investigated. |