2012 年 78 巻 790 号 p. 2037-2047
The complex shear modulus and shape of the island particles which were constituents of polymer blends having sea-island morphology were examined in order to realize the polymer with high stiffness and loss factor suitable for vibration damping plates of the unconstrained type. The macroscopic storage modulus and loss factor were calculated by using the equations including variables such as storage shear modulus, loss factor, volume fraction and aspect ratio of the particles of multiple types explicitly which were derived in previous paper by using the equivalent inclusion method conbined with the Mori-Tanaka averaging theorem. Calculations of the macroscopic storage modulus and loss factor were carried out by varying the variables of the particles continuously assuming that polypropylene and stylene elastomer were used as matrix and prticles, respectively. Calculated results show that the macroscopic storage modulus and the loss factor can be increased simultaneously by decreasing aspect ratio of the particles and adding almina particles with the optimum range of the aspect ratio into the matrix. Moreover, the thickess of the polymer layer can be decreased to twice of the aluminum base plate.