Premium
Synthesis and Liquid Crystalline Properties of Poly(ethylene oxide) Brushes with Amphiphilic Side Groups
Author(s) -
Kim JongUk,
Lee JongChan
Publication year - 2005
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.200400507
Subject(s) - ethylene oxide , ethylene , side chain , oxide , polymer chemistry , materials science , polymer , crystallinity , differential scanning calorimetry , chemistry , crystallography , organic chemistry , copolymer , composite material , catalysis , physics , thermodynamics
Summary: Poly(ethylene oxide)s containing decylthiomethyl (DTP), decylsulfonylmethyl (DSP), methyl‐oligo(ethylene oxide) thiomethyl (M n OTP), methyl‐oligo(ethylene oxide) sulfonylmethyl (M n OSP), decyl‐oligo(ethylene oxide) thiomethyl (D n OTP), and decyl‐oligo(ethylene oxide) sulfonylmethyl (D n OSP) groups in the side‐chains, where n (the number of ethylene oxide units) = 1, 2, 3, or 4 for D n OTP and D n OSP, and n = 2, 3, or 7 for M n OTP and M n OSP, were synthesized to study the effect of the structure of the side‐chains on the ordered phases of the polymers. All of the M n OSPs, as well as M2OTP and M3OTP, were found to be amorphous polymers. DTP, M7OTP, D1OTP, D2OTP, and D3OTP showed crystalline phases below their isotropic temperatures. DSP, D1OSP, D2OSP, D3OSP, D4OSP, and D4OTP were found to be liquid crystalline. Therefore, the phase separation facilitated by the introduction of the sulfone group and/or by the addition of the longer ethylene oxide units between the ethylene oxide backbones and the hydrophobic decyl tails was found to be a key factor in the formation of the liquid crystalline phases. These ordered phases were characterized using differential scanning calorimetry, polarized optical microscopy, and X‐ray diffraction.Schematic illustration of the structures of poly(ethylene oxide) brushes showing liquid crystalline phases.