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. 2021 Jan 20;13(3):328. doi: 10.3390/polym13030328
Rheological quantities
Storage modulus G′
Loss modulus G″
Phase angle δ
Complex viscosity function |η*|(ω)
zero shear-rate viscosity η0
Magnitude of the complex modulus |G*|
Angular frequency ω
Relaxation strength H
Relaxation time τ
Hencky strain rate ϵ˙ 
crossover frequency ωc (ω of G′=G″)
temperature dependence according to Williams-Landel-Ferry’s law (based on free volume and not on potential barrier) WLF-temperature dependence
shift factor aT
Arrhenius activation energy Ea
Activation energy spectrum determined from shifting δ(ω) Ea(δ)
Activation energy spectrum determined from shifting G’(ω) Ea(G′)
Activation energy spectrum determined from shifting G”(ω) Ea(G″)
Maximum activation energy, determined from Ea(δ) Ea,max
Phase angle at which Ea,max is found δmax
Critical phase angle according to definition of Trinkle et al. [73] δc
Slope of phase angle dδ/dlogω
Material with an LCB-mPE-like thermorheologically complex behavior [62] LCB-mPE-like behavior (BL), BL-material
Material with an LDPE-like thermorheologically complex behavior [62] LDPE-like behavior (BH), BH-material
Material with a comb-PE-like thermorheologically complex behavior [62] comb-PE -like behavior (BC), BC-material
Molecular quantities
number-average molar mass Mn
weight-average molar mass Mw
z-average molar mass Mz
Polydispersity index Mw/Mn
molar mass distribution MMD
long-chain branches LCBs
Material types
long-chain branched metallocene catalyzed polyethylene LCB-mPE
long-chain branched metallocene catalyzed high densitypolyethylene LCB-mHDPE
long-chain branched metallocene catalyzed linear low densitypolyethylene LCB-mLLDPE
low-density polyethylene LDPE
linear low density Ziegler-Natta polyethylene ZN-LLDPE
high density Ziegler-Natta polyethylene ZN-HDPE
Miscellaneous
Logarithm (base 10) log
Weight % wt.%