Two color flow birefringence

Figure 8.4 Two-color flow birefringence apparatus. CSgrcen color splitter passing the...

Optical measurements often have a greater sensitivity compared with mechanical measurements. Semidilute polymers, for example, may not be sufficiently viscous to permit reliable transient stress measurements or steady state normal stress measurements. Chow and coworkers [113] used two-color flow birefringence to study semidilute solutions of the semirigid biopolymer, collagen, and used the results to test the Doi and Edwards model discussed in section 7.1.6.4. That work concluded that the model could successfully account for the observed birefringence and orientation angles if modifications to the model proposed by Marrucci and Grizzuti [114] that account for polydispersity, were used. 

A.W. Chow, and G.G. Fuller, The rheo-optical response of rod-like chains subject to transient shear flow. Part I Model calculations on the effects of polydispersity, Macromolecules 18, 786 (1985) A.W. Chow, G.G. Fuller, D.G. Wallace and J.A. Madri, The rheo-optical response of rod-like chains subject to transient shear flow. Part II. Two-color flow birefringence measurements, Macromolecules 18,793 (1985) A.W. Chow, G.G. Fuller, D.G. Wallace and J.A. Madri, The rheo-optical response of rod-like shortened collagen protein to transient shear flow, Macromolecules, 18, 805 (1985). 

A. Chow, G. Fuller, D. Wallace, and J. Madri, Rheo-optical response of rod-like chains subject to transient shear flow 2. Two-color flow birefringence measurements on collagen protein. Macromolecules, 18,793-804,1985. 

A.W. Chow and G.G. Fuller, Response of moderately concentrated xanthan gum solutions to time-dependent flows using two-color birefringence, J. Rheol., 28, 23 (1984). 

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