Yeerlan Adeli, Thulasinath Raman Venkatesan, Frank A. Nüesch, Dorina M. Opris
{"title":"Elastomers Based on Polynorbornene with Polar Polysiloxane Brushes for Soft Transducer Applications","authors":"Yeerlan Adeli, Thulasinath Raman Venkatesan, Frank A. Nüesch, Dorina M. Opris","doi":"10.1002/hlca.202400032","DOIUrl":null,"url":null,"abstract":"<p>Elastomers based on cross-linked bottlebrush polymers combine an extreme softness at low strains with a strain-stiffening effect, which makes them attractive as active components in dielectric elastomer actuators (DEA). Their main disadvantage concerns the small relative permittivity, which is about 3.5, requiring relatively high driving voltage in actuators. We synthesized a bottlebrush polymer elastomer with polar brushes, which exhibit an enhanced dielectric permittivity of 4.4. Anionic ring-opening polymerization of a polar cyclosiloxane gave telechelic polar brushes, while ring-opening polymerization of a norbornene macromonomer gave a bottlebrush polymer which was cross-linked to elastomers by a thiol-ene reaction. Elastomers with a small elastic modulus below 100 kPa, strain at break exceeding 100 %, attractive elasticity, and small mechanical loss factors (<i>tanδ</i>) were achieved. Temperature-dependent impedance measurements revealed a transition temperature of −95 °C and an interfacial polarization. The multigram scale synthesis demonstrates the potential for scaling up, which opens the door to broader applications of these materials beyond actuators, such as capacitive sensors, batteries, and electroluminescent devices. Notably, these devices operate at extremely low voltages where the dielectric breakdown does not limit their functionality, but still, the softness and the increased dielectric permittivity are a plus.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 8","pages":""},"PeriodicalIF":1.5000,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400032","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Helvetica Chimica Acta","FirstCategoryId":"92","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/hlca.202400032","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Elastomers based on cross-linked bottlebrush polymers combine an extreme softness at low strains with a strain-stiffening effect, which makes them attractive as active components in dielectric elastomer actuators (DEA). Their main disadvantage concerns the small relative permittivity, which is about 3.5, requiring relatively high driving voltage in actuators. We synthesized a bottlebrush polymer elastomer with polar brushes, which exhibit an enhanced dielectric permittivity of 4.4. Anionic ring-opening polymerization of a polar cyclosiloxane gave telechelic polar brushes, while ring-opening polymerization of a norbornene macromonomer gave a bottlebrush polymer which was cross-linked to elastomers by a thiol-ene reaction. Elastomers with a small elastic modulus below 100 kPa, strain at break exceeding 100 %, attractive elasticity, and small mechanical loss factors (tanδ) were achieved. Temperature-dependent impedance measurements revealed a transition temperature of −95 °C and an interfacial polarization. The multigram scale synthesis demonstrates the potential for scaling up, which opens the door to broader applications of these materials beyond actuators, such as capacitive sensors, batteries, and electroluminescent devices. Notably, these devices operate at extremely low voltages where the dielectric breakdown does not limit their functionality, but still, the softness and the increased dielectric permittivity are a plus.
期刊介绍:
Helvetica Chimica Acta, founded by the Swiss Chemical Society in 1917, is a monthly multidisciplinary journal dedicated to the dissemination of knowledge in all disciplines of chemistry (organic, inorganic, physical, technical, theoretical and analytical chemistry) as well as research at the interface with other sciences, where molecular aspects are key to the findings. Helvetica Chimica Acta is committed to the publication of original, high quality papers at the frontier of scientific research. All contributions will be peer reviewed with the highest possible standards and published within 3 months of receipt, with no restriction on the length of the papers and in full color.