Chiral nematic octasilsesquioxanes

I M  Saez; J W  Goodby

doi:10.1039/b105350g

Chiral nematic octasilsesquioxanes

I M Saez, J W Goodby

Chemistry

Research output: Contribution to journal › Article › peer-review

Abstract

The octasilsesquioxane cage has been successfully derivatised by platinum-catalysed hydrosilylation reaction of the alkene functionality of appropriate laterally substituted, chiral mesogenic moieties to yield monodisperse multipodal octamers. The liquid-crystalline silsesquioxanes were characterised by multinuclear MR, SEC, TGA, POM and X-ray diffractometry. The giant supermolecular materials display remarkably wide temperature range enantiotropic chiral nematic phases and glass transitions near to room temperature. One of the materials is iridescent and has properties similar to a low molar mass material even though it has a size approaching that of a small globular protein. Thus these observations raise questions as to whether the materials act as singular molecular entities or as spherical side chain polymers.

Original language	English
Pages (from-to)	2845-2851
Number of pages	7
Journal	Journal of Materials Chemistry
Volume	11
Issue number	11
DOIs	https://doi.org/10.1039/b105350g
Publication status	Published - 2001

Keywords

SIDE-CHAIN POLYMERS
LIQUID-CRYSTALLINE
SILSESQUIOXANES
SILOXANE
DIFFRACTION
BACKBONE
CAGES
CORE

Access to Document

10.1039/b105350g

http://dx.doi.org/10.1039/b105350g

Cite this

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title = "Chiral nematic octasilsesquioxanes",

abstract = "The octasilsesquioxane cage has been successfully derivatised by platinum-catalysed hydrosilylation reaction of the alkene functionality of appropriate laterally substituted, chiral mesogenic moieties to yield monodisperse multipodal octamers. The liquid-crystalline silsesquioxanes were characterised by multinuclear MR, SEC, TGA, POM and X-ray diffractometry. The giant supermolecular materials display remarkably wide temperature range enantiotropic chiral nematic phases and glass transitions near to room temperature. One of the materials is iridescent and has properties similar to a low molar mass material even though it has a size approaching that of a small globular protein. Thus these observations raise questions as to whether the materials act as singular molecular entities or as spherical side chain polymers.",

keywords = "SIDE-CHAIN POLYMERS, LIQUID-CRYSTALLINE, SILSESQUIOXANES, SILOXANE, DIFFRACTION, BACKBONE, CAGES, CORE",

author = "Saez, {I M} and Goodby, {J W}",

year = "2001",

doi = "10.1039/b105350g",

language = "English",

volume = "11",

pages = "2845--2851",

journal = "Journal of Materials Chemistry",

issn = "0959-9428",

publisher = "The Royal Society of Chemistry",

number = "11",

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T1 - Chiral nematic octasilsesquioxanes

AU - Saez, I M

AU - Goodby, J W

PY - 2001

Y1 - 2001

N2 - The octasilsesquioxane cage has been successfully derivatised by platinum-catalysed hydrosilylation reaction of the alkene functionality of appropriate laterally substituted, chiral mesogenic moieties to yield monodisperse multipodal octamers. The liquid-crystalline silsesquioxanes were characterised by multinuclear MR, SEC, TGA, POM and X-ray diffractometry. The giant supermolecular materials display remarkably wide temperature range enantiotropic chiral nematic phases and glass transitions near to room temperature. One of the materials is iridescent and has properties similar to a low molar mass material even though it has a size approaching that of a small globular protein. Thus these observations raise questions as to whether the materials act as singular molecular entities or as spherical side chain polymers.

AB - The octasilsesquioxane cage has been successfully derivatised by platinum-catalysed hydrosilylation reaction of the alkene functionality of appropriate laterally substituted, chiral mesogenic moieties to yield monodisperse multipodal octamers. The liquid-crystalline silsesquioxanes were characterised by multinuclear MR, SEC, TGA, POM and X-ray diffractometry. The giant supermolecular materials display remarkably wide temperature range enantiotropic chiral nematic phases and glass transitions near to room temperature. One of the materials is iridescent and has properties similar to a low molar mass material even though it has a size approaching that of a small globular protein. Thus these observations raise questions as to whether the materials act as singular molecular entities or as spherical side chain polymers.

KW - SIDE-CHAIN POLYMERS

KW - LIQUID-CRYSTALLINE

KW - SILSESQUIOXANES

KW - SILOXANE

KW - DIFFRACTION

KW - BACKBONE

KW - CAGES

KW - CORE

U2 - 10.1039/b105350g

DO - 10.1039/b105350g

M3 - Article

SN - 0959-9428

VL - 11

SP - 2845

EP - 2851

JO - Journal of Materials Chemistry

JF - Journal of Materials Chemistry

IS - 11

ER -