This README_Supplementary_Data.txt file was generated on 2025-03-04 by Kathrin Marina Eckert (kathrin.eckert@tuhh) ------------------- GENERAL INFORMATION ------------------- Name: Jana Ihrens (ORCID: 0000-0002-8454-4886) Role/Function: Data collector (main contact person) Institution: Institute of Thermal Separation Processes, Hamburg University of Technology Address: Eißendorfer Straße 38, 21073 Hamburg, Germany Email: jana.ihrens@tuhh.de Name: Kathrin Marina Eckert (ORCID: 0000-0002-8454-4886) Role/Function: Data collector (main contact person) Institution: Institute of Thermal Separation Processes, Hamburg University of Technology Address: Eißendorfer Straße 38, 21073 Hamburg, Germany Email: kathrin.eckert@tuhh.de Name: Irina Smirnova (ORCID: 0000-0003-4503-4039) Role/Function: Principal Investigator Institution: Institute of Thermal Separation Processes, Hamburg University of Technology Address: Eißendorfer Straße 38, 21073 Hamburg, Germany Name: Thorsten A. Kern Role/Function: Principal Investigator (alternative contact person) Institution: Institute for Mechatronics in Mechanics, Hamburg University of Technology Address: Eißendorfer Straße 38, 21073 Hamburg, Germany Email: t.a.kern@tuhh.de Date of data collection: January 2023 - September 2024 Location of data collection: Institute of Mechatronics in Mechanics & Thermal Separation Processes, Hamburg University of Technology, Hamburg, Germany Funding: This project is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – SFB 1615 – 503850735. --------------------------- SHARING/ACCESS INFORMATION --------------------------- Title of data set: "Data Supplement to the Article: 'Structuring of electrorheological fluids in polymer matrices for miniature actuators'" DOI of data set: https://doi.org/10.15480/882.15053 Related publication: Jana Ihrens et al. "Structuring of electrorheological fluids in polymer matrices for miniature actuators". (2024) DOI of related article: https://doi.org/10.1016/j.heliyon.2024.e39138 Please cite the accepted version of this publication in case you use the data. Keywords: Actuators, Braille, Tactile display, Oleogels, Lyogels, Electrorheological fluids, Miniature actuator --------------------- DATA & FILE OVERVIEW --------------------- ### 1. Pressure.csv (creation date: 30.10.2024, version: 01) - **Description:** List of chemicals used in the study. - **Columns:** - Formulation: The formulation analyzed (Cornstarch, Cellulose oleogel, WPI oleogel, Reference) - Pressure: The pressure which could be applied before breakthrough the valve [bar]. ### 2. Shear_stress.csv (creation date: 30.10.2024, version: 01) - **Description:** Shear rate measured over varying shear rates. - **Columns:** - Formulation: The formulation analyzed (Cornstarch, Cellulose oleogel, WPI oleogel) - Shear rate: Shear rate applied to the mixture [1/s]. - Shear stress: Shear stress measured in the mixture [Pa]. - Error of shear stress: Error of shear stress in the mixture [Pa]. ### 3. Shear_viscosity.csv (creation date: 30.10.2024, version: 01) - **Description:** Shear viscosity measured over varying shear rates. - **Columns:** - Formulation: The formulation analyzed (Cornstarch, Cellulose oleogel, WPI oleogel) - Shear rate: Shear rate applied to the mixture [1/s]. - Shear viscosity: Shear viscosity measured in the mixture [Pa s]. - Error of shear viscosity: Error of shear viscosity in the mixture [Pa s]. ### 4. Sedimentation.csv (creation date: 30.10.2024, version: 01) - **Description:** Sedimentation analysis over 48 hours. - **Columns:** - Time: time of experiment [h], 0 to 48 hours experiment duration time analyzed. - Formulation: The formulation analyzed (Cornstarch, Cellulose, WPI) - Sedimentation ratio: Time-dependent ratio of suspended particle height to total liquid height --------------------------- METHODOLOGICAL INFORMATION --------------------------- The methodolical information can be found in the publication. 1. Electromechanical Setups Three setups were developed to analyze different gel formulations. The primary testing option utilizes a V-shaped plate setup, allowing for the adjustment of the distance between the plates for gel insertion. The gel formulations that respond in this setup were then tested in the second horizontal plate setup. Finally, a valve setup is use the applied force in practical applications. All setups were used with a PHYWE high voltage power supply, capable of delivering 0 to 10 kV with a maximum current of 2 mA to provide the necessary voltage. The detailed design plans can be found in the related publication. 2. Manufacturing of Gel Formulations The precursor materials of the considered gel types are cellulose (microcrystalline cellulose type II, JRS Pharma GmbH & Co. KG, Vivapure®) and whey protein isolate powder (WPI, BiPRO 9500 from Agropur, Longueuil, Canada). The synthesis of WPI and cellulose aerogel particles followed the procedures outlined by Jung et al. (https://doi.org/10.1016/j.foodhyd.2023.108758) and Schroeter et al. (https://doi.org/10.1007/s10570-020-03555-2). WPI microparticles were synthesized through a wet-milling step of the alcogels, while dried-milling was employed for the preparation of cellulose microparticles. The oleogels were prepared by adding the oil compound to the aerogel particles. Using this procedure, mixtures containing 12 wt% aerogels were produced. The final oleogels were collected by centrifugation afterwards, to separate them from the residual oil phase. Instead of sunflower oil, a mixture containing 55 wt% cornstarch (Unilever, Brussels, Belgium) and 45% rapseed oil (Brökelmann+Co, Hamm, Germany) was used. 3. Sedimentation analysis The ratio of suspended particle height to total liquid height was analyzed optically. Images were captured at various time intervals and subsequently evaluated. 4. Rheological analysis The rheology measurements were performed with a Malvern Kinexus Pro rheometer (KNX 2100, Malvern Instruments GmbH, Herrenberg, Germany) using an oscillating plate-plate geometry (PL65 S 3185 SS and CP4/40 SR5206 SS). ----------------- RESEARCH CONTEXT ----------------- Miniature actuators are essential for applications requiring compact size, precision, and affordability, such as braille displays. However, conventional actuation technologies often fail to meet these specific demands. This study explores the integration of electrorheological fluids (ERFs) into cellulose- and protein-based polymer matrices to address key limitations—especially sedimentation—by structuring the fluid in a polymer matrix. The central question is whether electrorheological fluids embedded in biopolymer matrices can overcome sedimentation and remain functionally effective for use in miniature actuators, particularly in applications like braille displays. Gel formulations were tested in V-shaped, horizontal plate, and valve system setups, revealing reversible structural changes and mechanical resistance under electric fields. The findings confirm that ERF-polymer composites maintain characteristic ER behavior, demonstrating their potential for miniature actuator applications. ---------------------------------- EXPLANATION OF MEASURED VARIABLES ---------------------------------- Sedimentation ratio: Defined as the time-dependent ratio of the suspended particle layer height to the total liquid height. This dimensionless parameter, ranging from 0 to 1, quantifies the relative sinking behavior of particles in suspension. Shear Stress: Shear stress values obtained during exposure of the gel mixture to specified shear rates [Pa]. Shear Viscosity: Shear viscosity values obtained during exposure of the gel mixture to specified shear rates [Pa·s]. Breakthrough Pressure: The highest pressure the gel mixture can withstand in the valve setup before a breakthrough is observed [bar]. -------------- ABBREVIATIONS -------------- WPI: Whey Protein Isolate, Whey protein used as precursor to create the polymer matrix.