Two cyclic olefin copolymers with the same comonomers and different monomer molar ratios were blended,and then the blends were satura ted in supercritical CO 2 at 20?MPa and various temperatures to prepare microc ellular cyclic olefin copolymer blends by means of pressure quench.The cell dens ity and cell diameter of microcellular polymers were calculated to investigate t he effects of temperature and blending ratio on cell structures.The higher tempe rature results in larger cell sizes and smaller cell densities.The cell density increases remarkably and cell diameter decreases with increase in the content of the ingredient with higher T g.It is found that the stiffness of the matri x is the only possible material property that accounts for the differences in ce ll structure of micorocellular cyclic olefin copolymer blends with different ble nding ratio.
