Comparison of the Langevin-network model with experiments

3 Comparison of the Langevin-network model with experiments 

Ac-rcAo- ( A2+-is the extension ratio of one of the generic eight chains. 

This gives a fractional extension rc/ nl) of the central chain of 

With this, the work of stretching W = NkT As rc/nl) for an assembly of chains N per unit volume, where As rc/nl) of the individual chain is given by eq. (6.45), and the defining expression for the nominal stress t2 (per initial area) 

Proceeding further from eq. (6.40), we estimate = 2700 g/mole for the entanglement molecular weight, or molecular weight between cross links, and N = 2.33 X 10 /m for the number density of molecules of the neoprene used at T = 293K and for an assumed material density ofp S l.Og/cm.  

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