| Recently, inorganic-organic polymer composites have caught a great deal of attention from many researchers. The addition of inorganic materials, especially inorganic materials with nano-scale, to organic polymer endows these organic materials many unique physical and chemical properties. So inorganic-organic polymer composites have been utilized extensively in structural materials, electronic or optical materials, and membrane materials, but only a few efforts have been made on the syntheses of grouting matetials. A double-component polyurethane (PU)/SiO2 nanocomposite for grouing was prepared, based on toluene-2,4-diisocyanate (TDI) as hard segment, poly (propylene glycol) diols as soft segment, 3,3'-dichloro-4, 4'-diaminodiphenymethane(MOCA) as chain extender and acetone as solvent, by two-step polymerization. The silica size and dispersion in the PU nanocomposite, rhological behavior, mechanical properties, thermal performance and the UV absorbance characteristic of the PU nanocomposite were investigated by transmission electron microscope (TEM), viscometry, mechanical tests, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and UV spectroscope respectively. The results showed that the silica disperses homogeneously and in nanometer scale in the PU matrix. The maximum values of the mechanical properties such as tensile strength, elongation at break and adhesive strength display as addition of silicas is about 2(wt)%. Both resistant to high and low temperature become much better compared with PU. And the UV absorbance of the PU nanocomposites increases at range of 290-330nm with increasing silica content in the PU nanocomposites. Compared to the similar materials at home and abroad, this kind of sample has better elasticity, higher adhesive intensity, it is very convenient to grout in highway, indicates much applied value.
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