Synthesis and Properties of Addition-Type Poly(norbornene)s with Siloxane Substituents

Vinyl addition copolymerization of norbornene with norbornene dervatives bearing siloxane substituent, three arm- cyclic- and phenyl siloxane groups, was realized in the presence of the binaruy Ni(acac)(2)/B(C6F5)(3) system. The resulting copolymers show good solubility in common organic solvents and posssess a very high grass transition temperature between 265 and 360 degrees C, depending on the content and structure of the siloxane groups. The incorporation of siloxane group linked to the polymer chain results in a significant increase in the mechanical flexibility of the corresponding films. Furthermore, the gas permeability is also dependent on the content and structure of the siloxane group and the films obtained for the polymers with three arm siloxane group (Si(OSiMe3)(3) display high oxygen permeability in the range of 39 to 239 Barrer.