TY - JOUR
T1 - Highly dielectric rubber bearing cyanoethyl group with various side-chain structures
AU - Matsuno, Ryosuke
AU - Takagaki, Yuusaku
AU - Ito, Takamasa
AU - Yoshikawa, Hitoshi
AU - Takamatsu, Shigeaki
AU - Takahara, Atsushi
N1 - Funding Information:
This research was supported by Adaptable and Seamless Technology transfer Program through Target-driven R&D (A-STEP, AS2525027M) from Japan Science and Technology Agency (JST). The authors are grateful to Kazunobu Hashimoto from Sumitomo Riko Company and former A-STEP member for contribution to the establishment of research system, Miki Shoiriki of Kyushu University, for great help in the DSC and GPC measurement support, Sachie Inoue of Kyushu University for great help in the NMR measurement support, Eri Okazaki of Kyushu University for great help in the FAB-MA measurement support, and Dr. Masaru Mukai of Kyushu University for helpful comments on the manuscript. NMR measurement was supported by Evaluation Center of Materials Properties and Function, Institute for Materials Chemistry and Engineering, Kyushu University. This work was the result of using research equipment shared in MEXT Project for promoting public utilization of advanced research infrastructure (Program for supporting introduction of the new sharing system) Grant Number JPMXS0422300120.
PY - 2020/11/24
Y1 - 2020/11/24
N2 - We synthesized rubbers including cyanoethyl groups and evaluated the effect of side-chain structures on dielectric properties, electrical properties at room temperature, and glass-transition temperatures (Tg). New monomers including cyanoethyl were synthesized via the thiol-ene reaction and esterification; these included 3-((2,4-dicyanobutyl)thio)propyl acrylate (DCEA3M) and 6-((2,4-dicyanobutyl)thio)hexyl acrylate (DCEA6M). Copolymers consisting of 2-cyanoethyl acrylate (CEA) and DCEA3M or DCEA6M were synthesized to obtain a rubber with a high dielectric constant. Reference copolymer samples with varying CN wt % consisted of CEA and acrylate monomers were also synthesized. Undesirable gelation occurred during polymerization of monomers including cyanoethyl; however, gelation could be resolved by changing the monomer concentration and reaction time. The copolymers exhibited a Tg of 5 °C or below, and the relative dielectric constant at 100 Hz was above 10. pDCEA3M exhibited the highest dielectric constant of 20.3 corresponding to a high CN wt % of 20.6%, and pDCEA6M displayed the lowest Tg of -33.2 °C due to the internal plasticization corresponding to the long side chain; however, the dielectric losses of pDCEA3M and pDCEA6M were as high as 3.2 and 7.7, respectively. On the other hand, p(CEA-DCEA3M) and p(CEA-DCEA6M) copolymerized with CEA could reduce the dielectric loss (∼2.4) while maintaining high dielectric constant (16.3-18.9) and low Tg (-22.9-3.36 °C). The copolymers also exhibited a high dielectric constant at a comparable volume resistivity (1010-1012 Ω·cm) compared to commercial rubbers. Such elastomers with high dielectric constant and low dielectric loss are expected to improve the performance of soft actuators.
AB - We synthesized rubbers including cyanoethyl groups and evaluated the effect of side-chain structures on dielectric properties, electrical properties at room temperature, and glass-transition temperatures (Tg). New monomers including cyanoethyl were synthesized via the thiol-ene reaction and esterification; these included 3-((2,4-dicyanobutyl)thio)propyl acrylate (DCEA3M) and 6-((2,4-dicyanobutyl)thio)hexyl acrylate (DCEA6M). Copolymers consisting of 2-cyanoethyl acrylate (CEA) and DCEA3M or DCEA6M were synthesized to obtain a rubber with a high dielectric constant. Reference copolymer samples with varying CN wt % consisted of CEA and acrylate monomers were also synthesized. Undesirable gelation occurred during polymerization of monomers including cyanoethyl; however, gelation could be resolved by changing the monomer concentration and reaction time. The copolymers exhibited a Tg of 5 °C or below, and the relative dielectric constant at 100 Hz was above 10. pDCEA3M exhibited the highest dielectric constant of 20.3 corresponding to a high CN wt % of 20.6%, and pDCEA6M displayed the lowest Tg of -33.2 °C due to the internal plasticization corresponding to the long side chain; however, the dielectric losses of pDCEA3M and pDCEA6M were as high as 3.2 and 7.7, respectively. On the other hand, p(CEA-DCEA3M) and p(CEA-DCEA6M) copolymerized with CEA could reduce the dielectric loss (∼2.4) while maintaining high dielectric constant (16.3-18.9) and low Tg (-22.9-3.36 °C). The copolymers also exhibited a high dielectric constant at a comparable volume resistivity (1010-1012 Ω·cm) compared to commercial rubbers. Such elastomers with high dielectric constant and low dielectric loss are expected to improve the performance of soft actuators.
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U2 - 10.1021/acs.macromol.0c01483
DO - 10.1021/acs.macromol.0c01483
M3 - Article
AN - SCOPUS:85096511158
VL - 53
SP - 10128
EP - 10136
JO - Macromolecules
JF - Macromolecules
SN - 0024-9297
IS - 22
ER -