Meridional orientation in biaxially aligned thin films of hairy-rod polyfluorene
(2007) In Crystal Growth & Design 7(9). p.1706-1711- Abstract
- The uniaxial chain alignment and equatorial patterning of poly [9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] (M-n = 29 kg/mol, M-w = 68 kg/mol) thin films atop rubbed polyimide substrates have been studied by grazing incidence X-ray diffraction. This specific molecular weight yields among the highest observed levels of chain alignment and optical anisotropy and, after thermal annealing, the sample undergoes transformation to a highly textured crystalline hexagonal phase. The two dominant equatorial orientations (i.e., types I and II crystallites) are found to have almost identical meridional orientation distributions. The X-ray deduced orientation is in quantitative agreement with that obtained by optical absorption measurements. It is also... (More)
- The uniaxial chain alignment and equatorial patterning of poly [9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] (M-n = 29 kg/mol, M-w = 68 kg/mol) thin films atop rubbed polyimide substrates have been studied by grazing incidence X-ray diffraction. This specific molecular weight yields among the highest observed levels of chain alignment and optical anisotropy and, after thermal annealing, the sample undergoes transformation to a highly textured crystalline hexagonal phase. The two dominant equatorial orientations (i.e., types I and II crystallites) are found to have almost identical meridional orientation distributions. The X-ray deduced orientation is in quantitative agreement with that obtained by optical absorption measurements. It is also shown that the equatorial ordering is paracrystalline in nature, and both type I and type II crystallites are similar in this respect. This equatorial scattering is superimposed on a background of a hexagonal phase polymer with a cylindrically isotropic orientation (type III). (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/688334
- author
- Knaapila, Matti LU ; Hase, Thomas P. A. ; Torkkeli, Mika ; Stepanyan, Roman ; Bouchenoire, Laurence ; Cheun, Hyeun-Seok ; Winokur, Michael J. and Monkman, Andrew P.
- organization
- publishing date
- 2007
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Crystal Growth & Design
- volume
- 7
- issue
- 9
- pages
- 1706 - 1711
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000249330900027
- scopus:34748875418
- ISSN
- 1528-7483
- DOI
- 10.1021/cg0607295
- language
- English
- LU publication?
- yes
- id
- a0214be6-89bd-4bd7-ad3c-2decf9f14783 (old id 688334)
- date added to LUP
- 2016-04-01 11:51:42
- date last changed
- 2022-01-26 19:20:28
@article{a0214be6-89bd-4bd7-ad3c-2decf9f14783, abstract = {{The uniaxial chain alignment and equatorial patterning of poly [9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] (M-n = 29 kg/mol, M-w = 68 kg/mol) thin films atop rubbed polyimide substrates have been studied by grazing incidence X-ray diffraction. This specific molecular weight yields among the highest observed levels of chain alignment and optical anisotropy and, after thermal annealing, the sample undergoes transformation to a highly textured crystalline hexagonal phase. The two dominant equatorial orientations (i.e., types I and II crystallites) are found to have almost identical meridional orientation distributions. The X-ray deduced orientation is in quantitative agreement with that obtained by optical absorption measurements. It is also shown that the equatorial ordering is paracrystalline in nature, and both type I and type II crystallites are similar in this respect. This equatorial scattering is superimposed on a background of a hexagonal phase polymer with a cylindrically isotropic orientation (type III).}}, author = {{Knaapila, Matti and Hase, Thomas P. A. and Torkkeli, Mika and Stepanyan, Roman and Bouchenoire, Laurence and Cheun, Hyeun-Seok and Winokur, Michael J. and Monkman, Andrew P.}}, issn = {{1528-7483}}, language = {{eng}}, number = {{9}}, pages = {{1706--1711}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Crystal Growth & Design}}, title = {{Meridional orientation in biaxially aligned thin films of hairy-rod polyfluorene}}, url = {{http://dx.doi.org/10.1021/cg0607295}}, doi = {{10.1021/cg0607295}}, volume = {{7}}, year = {{2007}}, }