Development of contractile ionic actuators based on ionoelastomers and CNT yarns for smart electroactive textile

3 years contract starting on January 1st 2023 at CY Cergy Paris Université (France)

Context

The Marie Skłodowska-Curie Actions Doctoral Network SOFTWEAR (SOFT actuators for Wearables, Exoskeletons, and Augmenting Robotics) will comprise 12 PhD students from 10 European Universities. SOFTWEAR is a highly interdisciplinary Doctoral Network in the emerging and rapidly growing field of wearables, with a unique focus on soft actuators for wearables and exoskeletons. The primary objective of SOFTWEAR is to train young researchers in the multidisciplinary science of soft actuators for integration in wearables and augmenting textiles. This will be achieved by merging chemistry, physics, mechanics, electronics, textile technology, design, human-technology interaction and ethics in a truly interdisciplinary manner, while teaching essential skills in ethics, product development, IPR and industrial realisation, thus providing a unique added value to the careers of the Researchers. This will be accomplished by on-the-job training on innovative research projects developing beyond-the-state-of-the-art soft actuator technology and integrating this into active garments and soft exoskeletons. The research will be carried out at leading academic groups and by immersion in applied projects at the industrial partners. The position will require traveling to participate in Training Schools and secondments of several months to academic and industrial associated partners.

For more information see www.softwear-dn.eu
 

Research Project

Electroactive yarns that could exhibit large contractile stroke and operate in open-air are strongly desired as actuating element of actuating textiles and garments. Among the different artificial muscle technologies, carbon nanotube (CNT) yarn muscles are especially promising because of their electrical control, low activation voltage and high electronic conductivity. They rely on the charging/discharging of the electrochemical double layer (EDLC) at the CNT-electrolyte interface through capacitive process, transducing a low-voltage electrochemical stimulation into mechanical response. Interestingly, when the neat CNT yarns are coiled by overtwisting, their spring-like structures can convert torsional electrochemical actuation into large tensile deformation. By combining two CNT yarns, respectively acting as anode and cathode, with an ionic conducting gel, it becomes possible to develop contractile yarn muscles operating in the open-air.^[1]

The project of the recruited PhD student aims at developing CNT yarn muscles for actuating textiles. He/she will first develop the ionic conducting coatings that will act as the ion source for open-air operation. The targeted materials will be ionoelastomers combining stretchability, toughness and ionic conductivity in the “dry” state, i.e. without containing any liquid phase or solvent. It will be achieved by the synthesis and the crosslinking of polymeric ionic liquids, a recent sub-class of polyelectrolytes presenting ionic liquid-like centers on their polymer backbone and ionic liquid-like counter-ions remaining mobile in the dry state thanks to their highly dissociated nature. They will be made ideally (i) safe for skin contact by choosing bio-friendly ions and (ii) hydrophobic to enable the washability of the targeted textile. In a second step, he/she will investigate the coating of these ionoelastomers on highly electronically conducting CNT yarns that can be coiled to enhance their electromechanical response. The fabrication of CNT yarns by dry spinning of long and dense CNT forest produced by Chemical Vapor Deposition (CVD) process ^[2] will be investigated and optimized during a 6 months visit at CEA Saclay (near Paris). The influence of the coiling state of the yarns as well as the nature of the ionoelastomer coatings on the electromechanical response will be investigated to enhance their linear contraction and their response speed. The integration of the ionoelastomer/CNT actuating yarns into knitted and woven textile constructions will be finally investigated during a 2 months visit at the University of Borås (Sweden) and a demonstrator will be produced during a 1 month visit at Elitac company (Germany).

Candidate profile

With a master degree in chemistry (ideally polymer chemistry and/or physical-chemistry), the highly motivated candidate will have an excellent scientific level, a strong multidisciplinary interest and a good adaptation capacity. The candidate must also have excellent communication skills and be fluent in English (both oral and written) to collaborate with the different involved partners. An experience in electrochemistry and/or smart textiles would be an advantage.
Host institution: CY Cergy Paris University
The recruited PhD student will be enrolled in the doctoral program of the doctoral school Science and Technics at CY Cergy Paris Université . The research will be performed in LPPI Lab and in partners’ labs during secondments. LPPI gathers 20 researchers and between 20 to 30 PhD students and postdocs in a motivating and innovative environment. The team is the result of collaboration between chemists, electrochemists, physico-chemists of polymers and of surfaces and interfaces. LPPI has an internationally recognized experience in the development of electroactive polymers and actuators, especially based on the synthesis and combination of electronic and ionic conducting materials.

Benefits

As a member of the MSCA-SOFTWEAR Doctoral Network, the recruited PhD student will have access to several benefits:

• A thorough scientific education in the frame of a doctoral training program.
• The possibility to participate in specific international courses, workshops and conferences.
• A strong involvement in a European research project with high international visibility.
• The possibility to perform research visits to internationally renowned research labs in Europe.
• Obtaining an interdisciplinary and intersectorial (academic/industry) experience
• A prestigious three-year MSCA Fellowship.
• A competitive salary including mobility and family allowances.

Eligibility criteria

Early-Stage Researchers must, at the time of recruitment, hold a Master's degree in polymer or material chemistry and have not yet been awarded a doctoral degree.

At the time of recruitment researchers must not have resided or carried out their main activity (work, studies, etc) in the country (i.e France) where they are applying for more than 12 months in the 3 years immediately prior to the reference date.

How to apply

Send your resume, motivation letter, Master diploma marks and recommendation letters from two references at: Cedric Plesse: cedric.plesse@cyu.fr


[1] Chu et al., Science 371, 494–498 (2021) https://doi.org/10.1126/science.abc4538
[2] https://iramis.cea.fr/nimbe/ledna/index.php