Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots
Biomimetic actuators are typically constructed as functional bi- or multilayers, where actuating and resistance layers together dictate bending responses upon triggering by environmental stimuli. Inspired by motile plant structures, like the stems of the false rose of Jericho (<i>Selaginella l...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-01-01
|
| Series: | Biomimetics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2313-7673/8/1/43 |
| _version_ | 1797613256253112320 |
|---|---|
| author | Jan-Lukas Schäfer Tobias Meckel Simon Poppinga Markus Biesalski |
| author_facet | Jan-Lukas Schäfer Tobias Meckel Simon Poppinga Markus Biesalski |
| author_sort | Jan-Lukas Schäfer |
| collection | DOAJ |
| description | Biomimetic actuators are typically constructed as functional bi- or multilayers, where actuating and resistance layers together dictate bending responses upon triggering by environmental stimuli. Inspired by motile plant structures, like the stems of the false rose of Jericho (<i>Selaginella lepidophylla</i>), we introduce polymer-modified paper sheets that can act as soft robotic single-layer actuators capable of hygro-responsive bending reactions. A tailored gradient modification of the paper sheet along its thickness entails increased dry and wet tensile strength and allows at the same time for hygro-responsiveness. For the fabrication of such single-layer paper devices, the adsorption behavior of a cross-linkable polymer to cellulose fiber networks was first evaluated. By using different concentrations and drying procedures fine-tuned polymer gradients throughout the thickness can be achieved. Due to the covalent cross-linking of polymer with fibers, these paper samples possess significantly increased dry and wet tensile strength properties. We furthermore investigated these gradient papers with respect to a mechanical deflection during humidity cycling. The highest humidity sensitivity is achieved using eucalyptus paper with a grammage of 150 g m<sup>−2</sup> modified with the polymer dissolved in IPA (~13 wt%) possessing a polymer gradient. Our study presents a straightforward approach for the design of novel hygroscopic, paper-based single-layer actuators, which have a high potential for diverse soft robotic and sensor applications. |
| first_indexed | 2024-03-11T06:53:18Z |
| format | Article |
| id | doaj.art-2f3bde74a4e74c1abf223afc1053da7e |
| institution | Directory Open Access Journal |
| issn | 2313-7673 |
| language | English |
| last_indexed | 2024-03-11T06:53:18Z |
| publishDate | 2023-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biomimetics |
| spelling | doaj.art-2f3bde74a4e74c1abf223afc1053da7e2023-11-17T09:49:28ZengMDPI AGBiomimetics2313-76732023-01-01814310.3390/biomimetics8010043Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft RobotsJan-Lukas Schäfer0Tobias Meckel1Simon Poppinga2Markus Biesalski3Department of Chemistry, Macromolecular Chemistry & Paper Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, GermanyDepartment of Chemistry, Macromolecular Chemistry & Paper Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, GermanyDepartment of Biology, Botanical Garden, Technical University of Darmstadt, Schnittspahnstraße 10, 64287 Darmstadt, GermanyDepartment of Chemistry, Macromolecular Chemistry & Paper Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, GermanyBiomimetic actuators are typically constructed as functional bi- or multilayers, where actuating and resistance layers together dictate bending responses upon triggering by environmental stimuli. Inspired by motile plant structures, like the stems of the false rose of Jericho (<i>Selaginella lepidophylla</i>), we introduce polymer-modified paper sheets that can act as soft robotic single-layer actuators capable of hygro-responsive bending reactions. A tailored gradient modification of the paper sheet along its thickness entails increased dry and wet tensile strength and allows at the same time for hygro-responsiveness. For the fabrication of such single-layer paper devices, the adsorption behavior of a cross-linkable polymer to cellulose fiber networks was first evaluated. By using different concentrations and drying procedures fine-tuned polymer gradients throughout the thickness can be achieved. Due to the covalent cross-linking of polymer with fibers, these paper samples possess significantly increased dry and wet tensile strength properties. We furthermore investigated these gradient papers with respect to a mechanical deflection during humidity cycling. The highest humidity sensitivity is achieved using eucalyptus paper with a grammage of 150 g m<sup>−2</sup> modified with the polymer dissolved in IPA (~13 wt%) possessing a polymer gradient. Our study presents a straightforward approach for the design of novel hygroscopic, paper-based single-layer actuators, which have a high potential for diverse soft robotic and sensor applications.https://www.mdpi.com/2313-7673/8/1/43cellulosefibersheetpolymer adsorptionhumidity actuated devicesdirected transport |
| spellingShingle | Jan-Lukas Schäfer Tobias Meckel Simon Poppinga Markus Biesalski Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots Biomimetics cellulose fiber sheet polymer adsorption humidity actuated devices directed transport |
| title | Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots |
| title_full | Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots |
| title_fullStr | Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots |
| title_full_unstemmed | Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots |
| title_short | Chemical Gradients in Polymer-Modified Paper Sheets—Towards Single-Layer Biomimetic Soft Robots |
| title_sort | chemical gradients in polymer modified paper sheets towards single layer biomimetic soft robots |
| topic | cellulose fiber sheet polymer adsorption humidity actuated devices directed transport |
| url | https://www.mdpi.com/2313-7673/8/1/43 |
| work_keys_str_mv | AT janlukasschafer chemicalgradientsinpolymermodifiedpapersheetstowardssinglelayerbiomimeticsoftrobots AT tobiasmeckel chemicalgradientsinpolymermodifiedpapersheetstowardssinglelayerbiomimeticsoftrobots AT simonpoppinga chemicalgradientsinpolymermodifiedpapersheetstowardssinglelayerbiomimeticsoftrobots AT markusbiesalski chemicalgradientsinpolymermodifiedpapersheetstowardssinglelayerbiomimeticsoftrobots |