Butene-1 (co)polymers characterized by the following properties:
content of butene-1 units in the form of isotactic pentads (mmmm) from 25 to 55%;
intrinsic viscosity [η] measured in tetraline at 135° C. from 1 to 3 dL/g;
content of xylene insoluble fraction at 0° C. from 3 to 60%; and
a ratio ES2/ES1≧1, where ES1 is the boiling diethyl ether soluble fraction determined on the polymer as such and ES2 is the boiling diethyl ether soluble fraction determined after milling the polymer.
The butene-1 (co)polymers show a good balance between processability and elastomeric behavior.
Butene-1(共)聚合物具有以下特性:异构
戊二烯单元的含量(mmmm)在25%至55%之间;在135℃下以四氢
萘测量的内禀粘度[η]为1至3 dL/g;在0℃下的二
甲苯不溶性分数为3%至60%;且ES2/ES1比率≥1,其中ES1是在聚合物本身上测定的沸腾二
乙醚可溶性分数,ES2是在研磨聚合物后测定的沸腾二
乙醚可溶性分数。Butene-1(共)聚合物在可加工性和弹性行为之间表现出良好的平衡。