단분산성 고분자 용융체의 완화시간분포의 해석적인 근사계산법

The relaxation time spectrum is a versatile parameter to calculate various polymer viscoelastic properties, such as the relaxation modulus (G(t)), dynamic modulus (G'(ω)) and loss modulus (G"(ω)). However, it cannot be measured experimentally. This study calculated the relaxation time spectrum using a calculation method based on Fusso-Kirkwood’s theoretical research and using the empirical loss modulus formula. The calculated relaxation time spectrum and Rouse’s model could describe the viscoelastic behavior of monodisperse polystyrene successfully. This analytical approximation of the relaxation time spectrum differed from experimental data in the intermediate region between the reputation and Rouse region. This may have resulted from a limitation of the molecular theory in the Rouse region.