Polystyrene axial ratio

Use these data to determine either rj or the yield value for these dispersions depending on whether or not the system is Newtonian. Are these results consistent with the fact that the axial ratio was nearer unity and the particle size distribution narrower for the polystyrene than the silica Explain. 

Riseman (139) or Kuhn and Kuhn (153 , 153"). For the sake of comparison, Fig. 12 also shows the theta-solvent intrinsic viscosities of polystyrene in cyclohexane [experimental valuesofKRiGBAUMandFuoRY (149), small black points theoretical values, broken line] and the theoretical intrinsic viscosities of rigid ellipsoids with axial ratios p = M/500 (chain curve). As a matter of course, the chain curve reduces to the Einstein value of [rf in the range of M below500 [see, for example, Petehlin (16) ]z. 

The anisotropy of polarizability can be positive (eg, polycarbonate) as well as negative (eg, polystyrene). This offers the possibility of minimizing birefringence by copolymerization or blending of suitable polymers with the right mixture ratio, eg, blends of poly(phenylene ether) (PPE) and polystyrene (PS). The magnitude of birefringence of axial-symmetrically oriented polymers vs their molecule orientation has been described (182). 

The polystyrene simulation followed the experiments of Bell and Edie (12) with good agreement. Figure 14.8 shows the simulation results for fiber spinning nylon-6.6 with a draw ratio of 40. The figure demonstrates the wealth of information provided by the model. It shows the velocity, temperature, axial normal stress, and crystallinity fields along the threadline. We see the characteristic exponential-like drop in diameter with locally (radially) constant but accelerating velocity. However, results map out the temperature, stress, and crystallinity fields, which show marked variation radially and axially. 

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