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Small-Angle Neutron Scattering Studies on the Phase Behavior of Binary Polymer Blends Driven by Photoisomerization
Published
Author(s)
O Urakawa, O Yano, Q Tran-Cong, A Nakatani, Charles C. Han
Abstract
The phase behavior of trans-stilbene-labeled polystyrene and poly [vinyl methyl ether] mixtures was investigated by using small angle neutron scattering. It was found that the binary interaction parameter, χ, obtained by analyzing the scattering functions with the random phase approximation theory increases as the trans-stilbene is converted to the cis-isomer. The dependence of χ on the fraction of trans- and cis-isomers in the blend was experimentally obtained and discussed using random copolymer theory. Furthermore, the temperature dependence of χ varies linearly with the reciprocal temperature. These experimental results directly reveal the possibility of controlling the miscibility of polymer blends by photochemical reactions such as photoisomerization.
Citation
Macromolecules
Volume
31
Issue
No. 22
Pub Type
Journals
Keywords
phase separation, photoisomerization, polymer blends, small angle neutron scattering
Citation
Urakawa, O.
, Yano, O.
, Tran-Cong, Q.
, Nakatani, A.
and Han, C.
(1998),
Small-Angle Neutron Scattering Studies on the Phase Behavior of Binary Polymer Blends Driven by Photoisomerization, Macromolecules
(Accessed November 7, 2025)