Empirical Estimation of Scattering Loss for Amorphous Polymers

Empirical Estimation of Scattering Loss for Amorphous Polymers 

The intrinsic molecular volume of monomer units for an amorphous polymer can be calculated from the atomic radius and bond length of the constituent atoms on the basis of the method developed by Slonimskii et al. [24]. When an atom B (atomic radius R) is bound to atom (atomic radius Ri) with bond length d, the atomic volume A.V B) of atom B is given by 

If the molecule consists of atoms B -Bj, the intrinsic molecular volume is given by 

K is the packing coefficient of the molecule its value for most amorphous polymers is known to be 0.68 [23]. The actual molecular volume of the monomer unit V is relatedtothe molecular weight between chain entanglementsAf, by [25] 

The number of chain atoms between physical entanglements, N, is expressed as 

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