Table 4.
Bioinspired and biomimetic adhesives
| Components | Adhesive design concept | Characteristics | Adhesion test on tissue/organ/substrate | Adhesion property | Ref. | |
|---|---|---|---|---|---|---|
| Lap shear strength (maximum, kPa) | Tensile adhesion strength (maximum, kPa) | |||||
| Silica ludox TM-50 nanoparticle, PDMA | Nanoparticles sticking on gels, which play as nodes in connecting polymer chains, also dissipate energy under stress | Water resistance, rapid adhesion | Lap shear adhesion tests on calf liver | Maximum adhesion energy on calf liver is 25 J/m2 | N/A | [106] |
| s-PUA, PET | Inspired by the dome-like protuberances and mimicked the octopus suckers’ geometry, pressure differentials between the inner and outer environment | Reversible wet/dry adhesion | Tensile adhesion tests on silicon wafer substrate under dry, moist, underwater and oil conditions | N/A | 25 (dry), 38 (moist), 41 (underwater), 180 (under oil) | [162] |
| PDMS | PDMS substrate modified with nanosucker arrays inspired from octopus’ suckers | Wet adhesion | Tensile adhesion tests on glass sheets in a dry and wet environment, adhesion area is 1 cm2 | N/A | 3 N (dry), 2.8 N (wet) | [164] |
| PDMS | Adhesion patch made with hexagonal architectures and various geometric parameters | Wet adhesion | Peeling off adhesion tests on Si wafer. Tensile adhesion tests on pigskin under dry and moist conditions | N/A | Maximum adhesion energy is 2.8 J/m2 (dry) and 2.3 J/m2 (wet) | [165] |
| Peeling energy is 16 J/m2 | ||||||
| Anodic aluminum oxide, PDMS | Nanopile interlocking, inspired from tree roots | Tunable stretchability, and used as strain sensors | Tensile adhesion tests on the rigid rod with epoxy resin | N/A | 26 000 | [166] |
| PDMS and PVDF | Two-phases adhesive: solid–liquid, mechanical dispersion of solid spheres and liquid | Repeatable stick-on different materials, no curing time | Lap shear adhesion tests on copper | 11 000 | N/A | [167] |
| PDMS | Bioinspired fibrillar adhesives, mushroom-like fibril array |
Liquid repellent | Hemispherical smooth glass probe glued to the PDMS (mushroom-like fibril array) film under dry, water, ethylene glycol, and MeOH conditions | 35 mN (dry), 37 mN (water), 28 mN (ethylene glycol), 7 mN (MeOH) | [168] | |
| PDMS | Skin adhesion films with elastomeric microfibers modified with mushroom-shaped tips | Wet adhesion | Attached to human skin with a 1 cm2 circular area | Maximum adhesion strength is 18 kPa | [169] | |
| Balanus albicostatus (cp 19 k) protein | Nanofibers, inspired from barnacles | Underwater adhesion | Tensile adhesion tests on mica | The maximum adhesion force is 1.6 N | [170] | |
| Hexagonal boron nitride, rhodium (h-BN/Rh [111]) | Mimicking gecko moves on a ceiling, adhesion of liquid glue on solid via static friction | Switchable wetting and adhesion | N/A | N/A | [171] | |
| PVS | Biomimetic adhesive patch, mushroom-shaped microstructure, pillar-shaped | Microstructure surface, biomimetic | Pull-off adhesion tests by glass sphere on microstructure surface |
The maximum pull-off force is 30 mN | [172] | |
| PDMS | Bioinspired from gecko-foot, micropillar-patterned PDMS | Adhesion on the rough surface | Pull off adhesion tests on rough glass | 3 kPa | [173] | |
PDMS polydimethylsiloxane, s-PUA polyurethane-acrlate, PET polyethylene terephthalate, PVDF polyvinylidene fluoride, PDMA poly(dimethylacrylamide), PVS polyvinyl siloxane