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Natural rubber （NR）/trans-1,4-polyisoprene （TPI） composites with shape memory effect were prepared, and the effect of carbon nanotubes （CNTs） amount on the properties of the composites was studied. The results showed that with the increase of CNTS, the scorch time and curing time of the composites were shortened, and the curing rate and crosslinking density were slightly increased, and the tensile strength, modulus and hardness all showed an obvious upward trend, while the elongation at break did not change significantly, indicating that CNTs played a reinforcing role. However, the shape fixation rate decreased from 91.83% to 86.64%, and the shape recovery rate dropped from 95.43% to 90.76% in the shape memory properties. When the amount of CNTs was 6 phr（mass） and the DC voltage was above 80 V, the composites exhibited good electrical stimulation shape memory behavior.

A series of well-defined iminopyridine-titanium complexes were prepared and characterized by nuclear magnetic resonance spectroscopy, X-ray diffraction analysis and elemental analysis. Isoprene polymerization was carried out by using those complexes as main catalyst and dried methylaluminoxane as cocatalyst.The results showed that the iminopyridine-titanium complexes with strong electron-donating group possessed high activity （up to 6.3×104 g/（mol·h））, high cis-1,4 -unit selectivity (up to 74%) and excellent thermo-stability（up to 90 ℃）. The increased steric hindrance of substituent groups would significantly reduce the catalytic acti-vity, molecular weight and cis-1,4-unit selectivity. These results indicated that the ligand structure had more effects on activity than stereo-selectivity.