| 초록 |
The shape memory polyurethane-silica hybrid nanocomposites have been synthesized by sol-gel reactions between the surface silanole groups of fumed silica and hydrolysed VTMS used as chain extender of the HEA-terminated PU prepolymers. It has been shown that the silica particles incorporated into the polymer chains give dual effects as multifunctional chemical cross-links and reinforcing fillers. The static/dynamic mechanical properties measured by DMTA and UTM showed that these properties have significantly been improved with the addition and increasing content of silica. Silica particles incorporated into the PU chains become multifunctional chemical crosslinkers, and provide the materials with enhanced reinforcing effect in terms of initial and rubbery moduli, and strengths, yield and break strengths, thermal stability, shape memory performance as compared with simple mixing with silica. |
