Properties of amorphous and crystallizable hydrocarbon polymers. I. Melt rheology of fractions of linear polyethylene

摘要: The dynamic moduli G′(ω) and G″(ω) for two groups of linear polyethylene fractions (reported Mw/Mn < 1.2) were measured in the melt state using eccentric rotating disk method. Values zero shear viscosity η0 obtained compared with published results on similar fractions. Molecular weight data converted to a common basis through intrinsic viscosities trichlorobenzene (TCB) at 135°C. With recent Mw (light scattering) vs. [η]TCB, polyethylene, relationship 190°C, = 3.40 × 10−14(Mw)3.60, was obtained. flow activation energy Ea 6.4 kcal (T 140–195°C). plateau modulus G 190°C determined from area under loss peak one high-molecular-weight sample. value obtained, 1.58 107 dyn/cm2, corresponds an apparent molecular between entanglements 1850. storage compliance J′(ω) becomes anomalously large low frequencies. recoverable J could not be any