Infusing MemorySil with graphene creates a highly responsive, flexible, shape-recovering touch sensor. Trinity College Dublin’s G-putty is a fluid-like, hypersensitive impact sensor that physically oozes over time.
Both rely on piezoresistivity: deforming the material disturbs a microscopic network of conductive graphene flakes, producing a large change in electrical resistance. Their chemistry, however, makes them behave very differently.
Mechanical comparison
| Graphene-infused MemorySil | G-putty (Trinity College Dublin) | |
|---|---|---|
| Base material | Cross-linked shape-memory silicone elastomer | Non-cross-linked silicone polymer (Silly Putty®) |
| Physical state | Solid elastomer that returns to a fixed mold | Viscous liquid that flows, slumps and melts into a puddle |
| Shape memory | True elastic memory: yields temporarily, then slowly restores its molded geometry | Fluid self-healing: flow lets graphene flakes float back together over time |
| Longevity | Retains component shape indefinitely under load | Eventually oozes, migrates or flattens under continuous pressure |
How graphene MemorySil behaves
- Sensor mechanism: pressing deforms the material and shifts the embedded graphene sheets apart, interrupting electrical pathways and producing a touch or pressure signal for a connected computer.
- Low-modulus sensitivity: because MemorySil yields to very low stiffness when pressed, a light touch deforms it deeply, giving high sensitivity with a soft interface.
- Controlled electrical recovery: it does not snap back like rubber nor stay deformed like putty. It recovers over seconds, re-forming graphene pathways at a controlled, measurable rate.
Versus G-putty
G-putty, invented by Prof. Jonathan Coleman’s team at Trinity College Dublin, is sensitive enough to measure a human pulse on skin or detect a spider’s footsteps. Its liquid behavior gives graphene flakes high mobility and a very high gauge factor.
Its limitation is that it behaves like a liquid over long periods: under a continuous load it slowly oozes sideways and loses form, so it must be sealed in a container. Graphene MemorySil keeps the soft, high-strain sensing behavior of a putty with the durability of a silicone rubber, and is reported to be nearly as sensitive, with nearly the same gauge factor. Curing it with graphene is a simple process.
Practical applications
- G-putty: printed sensor ink, wearable skin patches, acoustic or vibration monitors, sealed inside a protective casing.
- Graphene MemorySil: smart mattresses, robotic finger grips, and aerospace cushions that monitor posture and weight distribution over years of use.