{"title":"The anti-freezing, water-resistant, adhesive, and solvent-free polyionic gels for wireless and underwater strain sensing","authors":"Haiyan Du, Yifan Zhao, Nan Zhang, Jun Shen","doi":"10.1007/s00396-025-05465-w","DOIUrl":null,"url":null,"abstract":"<div><p>The anti-freezing and water-resistant gels strain sensors have great potential applications in flexible wearable devices, underwater communication, and deep-sea exploration. However, the poor adhesion, high swelling, low stretchability, or decreased conductivity of most gels in water hinders the stable signal transmission of the strain sensors. In this work, multifunctional polyionic gels with anti-freezing, water resistance, high adhesion, and wireless strain sensing ability were prepared by the one-step ultraviolet (UV) initiated copolymerization of butyl acrylate (BA), acrylic acid (AA), and 1-allyl-3-octylimidazole tetrafluoroborate ([AOIM][BF<sub>4</sub>]). The high-density ionic groups in the macromolecular chains of poly(1-allyl-3-octylimidazole tetrafluoroborate) (P[AOIM][BF<sub>4</sub>]) endowed the gels with excellent conductivity, which made the gel strain sensors suitable for monitoring the human joint movements, speech recognition, and other strain sensing. Because polybutyl acrylate (PBA) and P[AOIM][BF<sub>4</sub>] are hydrophobic polymers, water molecules are hardly dispersed into the gel matrix, and the gels could maintain good flexibility and conductivity underwater or at low temperature. The gel sensors were connected with the wireless signal transmission module, which monitored finger tapping underwater, speech recognition, and human joint movement at − 20 ℃. The anti-freezing and water-resistant properties depended on the P[AOIM][BF<sub>4</sub>] content in the gels. The anti-freezing, water resistance, and high adhesion provide the polyionic gels with new application prospects in telemedicine health, underwater communications, etc. Using UV irradiation to copolymerize ionic liquid monomers with traditional monomers for preparing the polyionic gels is efficient, environmentally friendly, and free of solvents. The strategy to fabricate the multifunctional gels could be expanded to other functional soft matters.</p><h3>Graphical Abstract</h3><p>The multifunctional polyionic gels could be used for underwater communication, speech recognition, and wireless motion monitoring at − 20 ℃.</p>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":520,"journal":{"name":"Colloid and Polymer Science","volume":"303 10","pages":"2041 - 2053"},"PeriodicalIF":2.3000,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Colloid and Polymer Science","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s00396-025-05465-w","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The anti-freezing and water-resistant gels strain sensors have great potential applications in flexible wearable devices, underwater communication, and deep-sea exploration. However, the poor adhesion, high swelling, low stretchability, or decreased conductivity of most gels in water hinders the stable signal transmission of the strain sensors. In this work, multifunctional polyionic gels with anti-freezing, water resistance, high adhesion, and wireless strain sensing ability were prepared by the one-step ultraviolet (UV) initiated copolymerization of butyl acrylate (BA), acrylic acid (AA), and 1-allyl-3-octylimidazole tetrafluoroborate ([AOIM][BF4]). The high-density ionic groups in the macromolecular chains of poly(1-allyl-3-octylimidazole tetrafluoroborate) (P[AOIM][BF4]) endowed the gels with excellent conductivity, which made the gel strain sensors suitable for monitoring the human joint movements, speech recognition, and other strain sensing. Because polybutyl acrylate (PBA) and P[AOIM][BF4] are hydrophobic polymers, water molecules are hardly dispersed into the gel matrix, and the gels could maintain good flexibility and conductivity underwater or at low temperature. The gel sensors were connected with the wireless signal transmission module, which monitored finger tapping underwater, speech recognition, and human joint movement at − 20 ℃. The anti-freezing and water-resistant properties depended on the P[AOIM][BF4] content in the gels. The anti-freezing, water resistance, and high adhesion provide the polyionic gels with new application prospects in telemedicine health, underwater communications, etc. Using UV irradiation to copolymerize ionic liquid monomers with traditional monomers for preparing the polyionic gels is efficient, environmentally friendly, and free of solvents. The strategy to fabricate the multifunctional gels could be expanded to other functional soft matters.
Graphical Abstract
The multifunctional polyionic gels could be used for underwater communication, speech recognition, and wireless motion monitoring at − 20 ℃.
期刊介绍:
Colloid and Polymer Science - a leading international journal of longstanding tradition - is devoted to colloid and polymer science and its interdisciplinary interactions. As such, it responds to a demand which has lost none of its actuality as revealed in the trends of contemporary materials science.