Polyurethane elastomer（PU） has good mechanical properties

widely used in the construction

furniture and clothing.With its applications are more and more widely

the requirements of PU in mechanical performance were increasingly high

in order to reduce cost of production under the premise of improving the mechanical strength of the polyurethane elastomer.The inorganic alumina（Al2O3） particles modified by supercritical ethanol（SCE-Al2O3） were used to enhance the performance of elastomer in this paper.4

4-diphenyl methane diisocyanate（MDI）

polyether glycols（PPG）

diethylenetriamine（DETA） and epoxy resin（E-51） were used as the main raw materials and synthesized two-component polyurethane elastomer by the use of acetone link to nitrogen

and then modified its properties by SCE-Al2O3

synthesized Al2O3/PU elastomer.Infrared spectroscopy（FT-IR）and X-ray diffraction（XRD） was used to characterize structure of the materials and the extent of change in Al2O3 crystal substrate

scanning electron microscopy（SEM） was used to observe dispersion of the Al2O3 in the matrix and to analyse the Al2O3 effect on the mechanical property of elastic including of tensile strength and elongation at break.The results of experiments showed that there was a little improved in the tensile strength and the elongation at break when the unmodified-Al2O3 was added in 1wt% and 2wt%

that was 19.22%

10.02% and 18.91%

8.96%.The tensile strength and the elongation at break was best when the content of SCE-Al2O3 was 2wt%

that was 7.76 MPa and 254%

improved 25.36%

26.37% and 13.95%

15.98% than that of pure PU and 2wt% unmodified-Al2O3

respectively.