Proceedings of International Forum for Green Asia 2017
Special issue of Evergreen - Joint Journal of Novel Carbon Resource Sciences & Green Asia StrategyP-28
Development of Norbornene-dicarboximide Based Organic Polymers forOptoelectronics
1Alisa Bannaron, Andrew M. Spring,2 Shiyoshi Yokoyama3
1

Interdisciplinary Graduate School of Engineering Sciences (IGSES), Kyushu University
2
Green Asia Education Center, Kyushu University
3
Institute for Materials Chemistry and Engineering (IMCE), Kyushu University
Kasuga koen, Kasuga, Fukuoka 816-8580, JapanAbstract
Side chain polymers containing three derivatives of norbornene-dicarboximide (NDI) basedmonomers were affectively synthesized in order to enhance thermal stability of organic polymer for
optoelectronic applications. While the amount of cyclohexyl-substituted and NSu, NTs-DACNsubstituted NDI monomers were constantly maintained, the content of phenyl vinylene thiophene
chromophore monomer was precisely varied from 0 wt% to 40 wt% in order to achieve applicableoptical activity. The polymerization was effectively performed via ring-opening metathesis
polymerization (ROMP) technique utilizing Grubbs 1st generation catalyst as an initiator.

1. Introduction
Electro-optic (EO) polymers have been
notably considered as the promising materials forapplications of potential optoelectronic devices
such as telecommunication, sensing, as well as,advanced computing. Recent progress leads to thedevelopment of polymers with several designs tomeet all required properties. Poly(norbornenedicarboximide)s (poly(NDI))s, which have been
firstly prepared in 1992 by ROMP, the reaction
has been confirmed the ability for both wellcontrolled
polymerization,and[1]
functionalization. Since then, the functionalizedpolymers have been extensively developed withseveral active groups to extend theirs range ofapplications. This includes the utilization inorganic electronic and optical applications
because of their essential thermal properties,
optical transparency, and film forming
characteristics.
In previous work, cyclohexyl-substituted
NDI monomer (1) was copolymerized with FTC
chromophore-NDI monomer (3) via ROMP using
Grubbs initiator, resulting in series of wellcontrolled copolymers with high Tg.[2] However,in order to further enhance thermal stability of thecopolymer, crosslinking is one of the potential
approaches to perform.

In this work, N-succinoyl-N’-ptoluenesulfonyl-4,8-diazacyclononyne(NSu,NTs-DACN) has been introduced as a pendant toNDI monomer (2) in order to crosslink withdiazide compound via Huisgen cycloaddition
reaction of an alkyne.[3]Scheme 1. NDI based copolymer containing three
NDI monomers

2. Results and discussion
2.1 Preparation of NDI monomers
The synthesis of NDI monomers (1) and(3) were reported in [3]. NSu, NTs-DACN wasoriginally investigated by Tomooka laboratory(Scheme 2). Then NSu, NTs-DACN wasconnected to NDI derivative monomer as inScheme 3 with the yield of 80%.

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Proceedings of International Forum for Green Asia 2017
Special issue of Evergreen - Joint Journal of Novel Carbon Resource Sciences & Green Asia Strategy

P-28
while the content of NDI monomer (3) was
gradually increase from 0 to 40 wt%. After theprecipitation, structures and molecular weights ofcopolymers were confirmed NMR and GPC asshown in Table 1.
Table 1. Molecular weight and PDI of copolymers
NDI monomer (3)Copolymer
MnPDI(wt%)
P-01
06442 1.43
P-02
208847 1.90
P-03309279 2.35
P-04407304 2.19Scheme 2. Synthesis of NSu, NTs-DACN

2.4 Deprotection of Cobalt moiety by CAN
After the completion of polymerization,
the copolymers containing cobalt complex weredeprotected by Cerium Ammonium Nitrate(CAN). Unfortunately, decomposition of FTC
chromophore on monomer (3) was observed
according to color change from green to yellow.
This is probably because of the interaction ofelectron deficient-cobalt complex and electron
rich-chromophore.

Scheme 3. Synthesis of NDI monomer (2)2.2 Investigation and protection of alkyne on
NDI monomer (2)Homo-polymerization of NDI monomer(2) was conducted in order to investigate thecompetitive reactivity of alkene and alkyne sites
on its monomer. However, it has been found thatalkyne on NSu, NTs-DACN was incompatible
with Grubbs initiator. Therefore, the particularalkyne was protected by using Co2(CO)8 (Scheme4). [4] The polymerization ability of protected NDI
monomer (2) was then confirmed by homopolymerization.

3. Conclusion
NDI monomers were successfullysynthesized and characterized. However, newapproach for introducing NSu, NTs-DACN has tobe conducted to avoid the use of protection
reaction. This could be achieved by postpolymerization. By this procedure, NSu, NTsDACN will be connected to NDI monomer afterpolymerization.
Acknowledgement
The author would like to express sincere gratitude
to Advance Graduate Program in Global Strategyfor Green Asia for research financial support.
References[1]

Scheme 4. Protection of alkyne on NDI monomer(2) by addition of Co2(CO)8[2]

2.3 Polymer synthesis and characterization
All copolymers were synthesized inanhydrous chloroform via ROMP using Grubbs
1st generation initiator at room temperature for 12hours. The amount of monomer (1) and (2) weremaintained at 0.3 g and 20 wt%, respectively,[3]

J. Asrar. Macromolecules, 1992, 23, 51505156.
A. M. Spring, F. Qiu, J. Hong, A. Bannaron,
S. Yokoyama, Polymer, 2017, 119, 13-27.
R. Ni, N. Mitsuda, T. Kashiwagi, K. Igawa,K. Tomooka, Angew. Chem. Int. Ed., 2015,54, 1190-1194.

Email: alisa.bann@s.kyushu-u.ac.jp76