CONFIGURATIONAL AND RHEOLOGICAL PROPERTIES OF CYCLIC POLYMERS

The configurational and theological properties of multiple-twisted rin g polymers, modelled as long cyclic finitely extensible bead-spring ch ains with internal distance constraints, have been calculated. This mo del corresponds to chemically cross-linked Rouse chains. The calculati ons were carried out for equilibrium and steady shear flow. The mean-s quare radius of gyration in equilibrium depends on the number of loops . In shear flow, non-Newtonian flow behaviour arises. The shear viscos ity and the first normal stress coefficient decrease with increasing s hear rate. The second normal stress coefficient is negative and much s maller than the first normal stress coefficient. Since the mean-square radius of gyration, shear viscosity and the first and second normal s tress coefficients depend on the number of loops, the latter can be de termined by four independent experiments.