Frequency dependence of intrinsic stress and birefringence tensor of bead/spring model of polymer solutions

Abstract

T he rece ntl y obtain ed c ompl e te so lution of Ih e s irn ult an eous diagonalizali on of matri ces H A a nd H in the hydrody na mi c diffu s ion equat ion has bas ic a ll y c han ged the diagona l va lues v" of the sy mme tri c malrix H of hydrod yna mic int e rac ti o n be lween a ll the beads of the e lasti c ra ndom c oil mod e l of th e iso la te d mac romo lecul e in soluti on. Si nce th ese va lu es ent er exp li citl y th e expression s for th e intrin sic stress and refracti ve in dex tensor in an a lt e rnating fl ow fi e ld if based on the conce pt o f inte rnal vi scos it y o f the model one had to reca lc ulat e a ll va lues obt a ined form erl y b y us in g the th e n ge ne ra ll y acce pt e d e rroneous se t of 11" data. Th e ne w vp e qua l uni ty independenl of p while th e old va lues were larger than 1 for small p and s ma ll e r for large p. He nce the ir too la rge contributi on s in th e fonn er range are partiall y compensated by th eir too small contributi on s in th e latt e r region. A s a c onsequence in the who le ran ge in vesti gat e d , be tween 3 and 3 00 c ha in link s, th e diffe re nces in rheo logica l and rhe oopti ca l e ffects are relat ive ly s mall, up to a fa c tor of 2, a lthough at hi ghe r link numbe r the diffe re nces le nd to grow wilh the logarithm of this numbe r.Key word s: Bead-sprin g mod el; eigenva lues; frequ ency res pon se ; intrin sic 0Pli cal tensor; intrinsic stress tensor; pol yme r soluti on.

Contribution of Polymer-Solvent Interactions to Dynamics of Linear Polymers in Dilute Solutions

“…[24,30] Its character is closely analogous to the dispersion of the ultrasound attenuation coefficient a/x 2 observed in dilute solutions about 10 7 Hz. This fact is currently used to describe the polymer dynamics specific for modes of K lying beyond the range [-K 0 , +K 0 ].…”

“…It is corresponding to the experimental data arising from measurements of the ultrasonic attenuation coefficient a/x 2 in polystyrene solutions. [24] 6 Calculation of the Intrinsic Viscosity [g(x)]…”