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Electronic Supplementary Information

Side-chain Polysiloxane Liquid Crystalline Elastomers from Non-

mesogenic Components†

K. Mohana and S. Umadevi*

Department of Industrial chemistry, School of Chemical Sciences, Alagappa University, Karaikudi-630 003, Tamilnadu, India.

*Corresponding Author

e-mail: umadevilc@gmail.com

Electronic Supplementary Material (ESI) for New Journal of Chemistry.This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2019

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Synthesis of 1-Phenyl-2(4-(undec-10-en-1-yloxy) phenyl)diazene, monomer (M)

NN

i. 11-bromo-1-undeceneii. K2CO3iii. KIdry butanone,80oC,18h

OH

NN

O

M

SchemeS1 Synthetic pathway followed to prepare olefinic terminated monomer M

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Fig.S1 FT - IR spectrum of azo monomer M

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Fig.S2 1H NMR spectrum of azo monomer M

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Fig.S3 DSC thermogram of azo monomer (M) recorded at a heating and cooling rate of

10°C/min

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Synthesis of crosslinker C1

i. 11-bromo-1-undeceneii. K2CO3iii. KIdry butanone18h, 80oC

OHHO

OCH2(CH2)8CH=CH2H2C=HC(H2C)8H2CO

C1

Scheme S2 Synthetic route to prepare vinyl terminated 11UB cross-linking agent, C1

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Fig.S4 FT-IR spectrum of cross-linker C1

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Fig.S5 1H spectrum of cross-linker C1

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Fig.S6 DSC thermogram of cross-linker (C1) recorded at a heating and cooling rate of 10°C/min

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Synthesis of biphenyl cross-linker C2

OHOH

i. 11-bromo-1-undeceneii. K2CO3iii. KIdry butanone18h, 80oC

OCH2(CH2)8CH CH2HC(H2C)8H2COH2C

C2

Scheme S3 Synthetic route for cross-linker C2

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Fig.S7 FT-IR spectrum of biphenyl cross-linker C2

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Fig. S8 1H spectrum of biphenyl containing cross-linkerC2

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Fig.S9 DSC thermogram of cross-linker (C2) recorded at a heating and cooling rate of 10°C/min

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Fig. S10 An optimised molecular model for the cross-linker C2 in a stretched all trans alkyl

chain conformation (from ACD chemlab-3D viewer).

Fig. S11 UV-Visible absorption spectra of azo monomer in toluene (a) by shining UV light at

254 nm; trans to cis isomerisation, (b) by shining visible light(>540);cis to trans isomerisation.

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Fig. S12 The peak absorbance of monomer (348nm) with respect to exposure time for (a) trans

to cis isomerisation and (b) cis to trans isomerisation.

Video S1: Bending of the LCE film upon UV irradiation (254nm)

Video S2: Unbending of the LCE film upon visible irradiation (>540 nm)