| 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. Degassed Poly (ethylene adipate) diol (Mn=2,000), dibutyltin dilaureate (0.02wt% based on reaction solution) and 1,4-BD were mixed. Then MDI and sonicated organoclay in DMF were added into the mixture to make 50wt% solution. The equivalent weight ratio of the components are 2.5:1:1.5 for MDI:PEA:1,4-BD. The reaction temperature was 65oC and the total reaction time was about 5hrs and final concentration of reaction mixture was 20wt%. The morphology, thermal and mechanical properties of the nanocomposite having the various contents (0.5wt%, 1wt%, 2wt% and 3wt%) of organoclay was investigated. |
