### Abstract

We have observed birefringence and depolarized light scattering patterns with 2-fold symmetry from a cylindrical diblock copolymer solution that was ordered under shear flow. We have developed a theory to account for such 2-fold symmetric scattering patterns, based on a model that assumes an anisotropic orientation distribution of ellipsoidal grains in the sample. We also show how scattering patterns can be approximately reduced to the sum of three terms of the form C
_{n}(θ) cos(nφ), where θ and φ are polar angles in the detection plane and n = 0,2, and 4. By comparing the experimentally determined C
_{n}(θ) functions with theoretical calculations, we estimated the fraction of the sample that is composed of misaligned grains, their size and eccentricity, and the angular range over which their optic axes were distributed (δθ). The analysis of the optical properties of these kinds of systems is complicated by the fact that the signal from misaligned grains diminishes extremely rapidly as δθ decreases.

Original language | English (US) |
---|---|

Pages (from-to) | 4185-4195 |

Number of pages | 11 |

Journal | Macromolecules |

Volume | 37 |

Issue number | 11 |

DOIs | |

State | Published - Jun 1 2004 |

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### ASJC Scopus subject areas

- Materials Chemistry

### Cite this

*Macromolecules*,

*37*(11), 4185-4195. https://doi.org/10.1021/ma035808t

**Birefringence and depolarized light scattering from ordered block copolymers with anisotropic distributions of grain orientations produced by shear flow.** / Abuzaina, Ferass M.; Garetz, Bruce; Mody, Jatin U.; Newstein, Maurice C.; Balsara, Nitash P.

Research output: Contribution to journal › Article

*Macromolecules*, vol. 37, no. 11, pp. 4185-4195. https://doi.org/10.1021/ma035808t

}

TY - JOUR

T1 - Birefringence and depolarized light scattering from ordered block copolymers with anisotropic distributions of grain orientations produced by shear flow

AU - Abuzaina, Ferass M.

AU - Garetz, Bruce

AU - Mody, Jatin U.

AU - Newstein, Maurice C.

AU - Balsara, Nitash P.

PY - 2004/6/1

Y1 - 2004/6/1

N2 - We have observed birefringence and depolarized light scattering patterns with 2-fold symmetry from a cylindrical diblock copolymer solution that was ordered under shear flow. We have developed a theory to account for such 2-fold symmetric scattering patterns, based on a model that assumes an anisotropic orientation distribution of ellipsoidal grains in the sample. We also show how scattering patterns can be approximately reduced to the sum of three terms of the form C n(θ) cos(nφ), where θ and φ are polar angles in the detection plane and n = 0,2, and 4. By comparing the experimentally determined C n(θ) functions with theoretical calculations, we estimated the fraction of the sample that is composed of misaligned grains, their size and eccentricity, and the angular range over which their optic axes were distributed (δθ). The analysis of the optical properties of these kinds of systems is complicated by the fact that the signal from misaligned grains diminishes extremely rapidly as δθ decreases.

AB - We have observed birefringence and depolarized light scattering patterns with 2-fold symmetry from a cylindrical diblock copolymer solution that was ordered under shear flow. We have developed a theory to account for such 2-fold symmetric scattering patterns, based on a model that assumes an anisotropic orientation distribution of ellipsoidal grains in the sample. We also show how scattering patterns can be approximately reduced to the sum of three terms of the form C n(θ) cos(nφ), where θ and φ are polar angles in the detection plane and n = 0,2, and 4. By comparing the experimentally determined C n(θ) functions with theoretical calculations, we estimated the fraction of the sample that is composed of misaligned grains, their size and eccentricity, and the angular range over which their optic axes were distributed (δθ). The analysis of the optical properties of these kinds of systems is complicated by the fact that the signal from misaligned grains diminishes extremely rapidly as δθ decreases.

UR - http://www.scopus.com/inward/record.url?scp=2942677249&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=2942677249&partnerID=8YFLogxK

U2 - 10.1021/ma035808t

DO - 10.1021/ma035808t

M3 - Article

AN - SCOPUS:2942677249

VL - 37

SP - 4185

EP - 4195

JO - Macromolecules

JF - Macromolecules

SN - 0024-9297

IS - 11

ER -