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6764387 
Journal Article 
Lamellar orientation of diblock copolymer solutions under steady shear flow 
Kitade, S; Ochiai, N; Takahashi, Y; Noda, I; Matsushita, Y; Karim, A; Nakatani, AI; Kim, HD; Han, CC; , 
1998 
1 
Macromolecules
ISSN: 0024-9297
EISSN: 1520-5835 
AMER CHEMICAL SOC 
WASHINGTON 
31 
23 
8083-8090 
English 
WOS:000077147800013 
The steady shear rate dependence of the structure of two poly(styrene-d(8)-b-2-vinylpyridine)s in alpha-chloronaphthalene, a common good solvent, was measured by small-angle neutron scattering (SANS) in a couette flow cell geometry in the ordered state, in which the solutions assume a lamellar structure (randomly oriented grains). SANS measurements revealed that steady shear flow induces macroscopic lamellar orientation at certain characteristic shear rates for the higher molecular weight sample (M-w = 3.6 x 10(5)). Lamellar normals are preferentially oriented along the vorticity direction at high shear rates. However, no shear effect was observed for the low molecular weight sample (M-w = 2.0 x 10(5)).