Advances in Biodegradable Soft Robots

Abstract

Biodegradable soft robots have been proposed for a variety of intelligent applications in soft robotics, flexible electronics, and bionics. Biodegradability offers an extraordinary functional advantage to soft robots for operations accompanying smart shape transformation in response to external stimuli such as heat, pH, and light. This review primarily surveyed the current advanced scientific and engineering strategies for integrating biodegradable materials within stimuli-responsive soft robots. It also focused on the fabrication methodologies of multiscale biodegradable soft robots, and highlighted the role of biodegradable soft robots in enhancing the multifunctional properties of drug delivery capsules, biopsy tools, smart actuators, and sensors. Lastly, the current challenges and perspectives on the future development of intelligent soft robots for operation in real environments were discussed.

Prominent processing techniques to manipulate semiconducting polymer microstructures

“…Moreover, in order to obtain uniform polymeric films, the fluid ridges that are formed behind the coating bar need to coalesce and level off. 173 Because the wire-bar technique can be used with many polymer-based solution formulations, it can deliver large-area films of controlled microstructures for a variety of (conjugated) polymers [216][217][218][219][220][221][222][223] and polymer-based blends [224][225][226][227][228] that find applications in research fields such as thermal 228 and thermoelectric 221,224 management, sensors, 216 electrochromic displays, 223 OFETs 217,218,220,222 and other microelectronics. 219 Therefore, there is a large variety of interesting film microstructures that could be wire-bar coated.…”

“…221 Other film microstructures were developed by controlling the film thickness and some specific processing parameters and include well-organized interconnected fibril networks of the difluorobenzothiadiazole-dithienosilole (PDFDT) copolymer, 222 crystalline paraelectric a-phase of poly(vinylidenefluoride) (PVDF) 219 and uniaxially aligned macroscopic structures and nanofibrils with large grains made of cyclopentadithiophenealt-benzothiadiazole (CDT-BTZ), cyclopentadithiophene-altfluorinated-benzothiadiazole (CDT-FBTZ) and cyclopentadithiophenealt-thiadiazolopyridine (CDT-PTZ) conjugated copolymers. 220 This section ends with few examples of film microstructures wire-bar coated from blends of polymers. Here, the most frequent are the (semi-)crystalline microstructures obtained from blends based on conjugated polymers that are optimized for their use in OFETs.…”

Sustainable Robots 4D Printing

“…Biodegradability gives soft robotics a huge advantage when it comes to tasks that require the robot to change its shape in response to things like heat, pH, and light. [ 31 ] The majority of biodegradable materials are produced in the form of polymers, which are classified as both natural and manufactured soft matter. Among the many naturally made biodegradable materials, protein‐based polymers, chitosan, cellulose, and gelatin are the natural polymers that are most often used to make biodegradable soft robots.…”

“…In general, 3D printing processes like fused filament fabrication (FFF), direct ink writing (DIW), inkjet, and poly jet provide excellent resolution and precision for pattern structures with autonomously programmed geometry and repeatability. [ 31 ] Nevertheless, FFF is the most extensively utilized of several 3D printing processes. [ 40 ] Due to material limitations, direct 3D printing of biodegradable soft robots has not yet become a widespread manufacturing approach.…”

Energy band gap modulation and photoinduced electron transfer fluorescence sensing properties of D–A conjugated polymers containing benzotriazole

“…Based on the above advantages, it is feasible to modulate the photovoltaic properties of polymer by selecting different donor and acceptor unit to regulate energy level. This approach has been widely employed in polymer light emitting diodes (PLEDs), [3][4][5] polymer field effect transistors (PFETs), [6][7][8] polymer solar cells (PSCs), [9][10][11][12] and other applications. [13][14][15] However, it has received little attention in the field of fluorescence sensing.…”