| 초록 |
Polyurethane (PU) flexible foams having shape memory effects have been synthesized from polyether polyol with silica and 2,4/2,6-toluene diisocyanate (TDI-80) following the one shot foaming method in the presence of water as the chemical blowing agent, silicone surfactant, cell-opener, blowing catalyst and tin catalyst. The effects of silica content on the performances of the foams have been extensively analyzed in terms of reactivity, cell morphology, mechanical and dynamic mechanical properties, shape memory properties and thermal properties of the foams.With increasing content of silica, thermal analysis indicated that the glass transition temperature of the polyurethane foam is about 40℃ and its thermal stability was obviously improved, compared with virgin polyurethane foam. The results from mechanical properties showed that the modulus, tensile strength and compressive strength could be obviously increased by adding functionalized silica particles to the polyurethane foam. |
