The present invention provides a modified conjugated diene polymer that is prepared by polymerization of a conjugated diene compound using a catalyst containing a lanthanoid rare earth element compound in an organic solvent and then modifying the resulting polymer having an active organic metal site with a modifier, wherein the modification efficiency is not less than 15% and the cis-1,4 bond content in the conjugated diene moiety measured by Fourier transform infrared spectroscopy satisfies the relationship (I):
or the modification efficiency is not less than 75% and the cis-1,4 bond content in the conjugated diene moiety measured by Fourier transform infrared spectroscopy satisfies the relationship (II):
The invention further provides a rubber composition containing the modified conjugated diene polymer and giving a tire exhibiting low heat build-up, satisfactory failure characteristics, and high abrasion resistance, and a tire composed of the rubber composition and exhibiting these characteristics.
本发明提供了一种改性共轭二烯聚合物,其制备方法是在有机溶剂中使用含有
镧系稀土元素化合物的催化剂对共轭二烯化合物进行聚合,然后用改性剂对所得到的具有活性有机
金属位点的聚合物进行改性,其中改性效率不低于 15%,通过傅里叶变换红外光谱法测量的共轭二烯分子中的顺式-1,4 键含量满足关系式(I):
或改性效率不低于 75%,且通过傅里叶变换红外光谱法测量的共轭二烯分子中的顺式-1,4 键含量满足关系式(II):
本发明进一步提供了一种含有改性共轭二烯聚合物的橡胶组合物,该组合物可提供一种具有低热积聚、令人满意的失效特性和高耐磨性的轮胎,以及一种由该橡胶组合物组成并具有上述特性的轮胎。