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Magnetic Field Triggered Multicycle Damage Sensing and Self Healing.

Ahmed AS, Ramanujan RV - Sci Rep (2015)

Bottom Line: Magpol exhibited a linear strain response upto 150% strain and complete recovery after healing.We have demonstrated the use of this concept in a reusable biomedical device i.e., coated guidewires.Our findings offer a new synergistic method to bestow multifunctionality for applications ranging from medical device coatings to adaptive wing structures.

View Article: PubMed Central - PubMed

Affiliation: School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore.

ABSTRACT
Multifunctional materials inspired by biological structures have attracted great interest, e.g. for wearable/ flexible "skin" and smart coatings. A current challenge in this area is to develop an artificial material which mimics biological skin by simultaneously displaying color change on damage as well as self healing of the damaged region. Here we report, for the first time, the development of a damage sensing and self healing magnet-polymer composite (Magpol), which actively responds to an external magnetic field. We incorporated reversible sensing using mechanochromic molecules in a shape memory thermoplastic matrix. Exposure to an alternating magnetic field (AMF) triggers shape recovery and facilitates damage repair. Magpol exhibited a linear strain response upto 150% strain and complete recovery after healing. We have demonstrated the use of this concept in a reusable biomedical device i.e., coated guidewires. Our findings offer a new synergistic method to bestow multifunctionality for applications ranging from medical device coatings to adaptive wing structures.

No MeSH data available.


Related in: MedlinePlus

DMA measurement of the Shape memory properties of Magpol with filler concentrations of 0, 12, 16, and 20 wt% over two cycles of unconstrained strain and recovery.
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f2: DMA measurement of the Shape memory properties of Magpol with filler concentrations of 0, 12, 16, and 20 wt% over two cycles of unconstrained strain and recovery.

Mentions: DMA results (Fig. 2) show that there is not much change in Tg with increased filler loading. The Tg ranges between −25 °C for 0 wt% loading to −20 °C for 20 wt% loading. At −80 °C, there is an increase in the storage modulus with loading. The storage modulus was found to be 1.5 GPa, 1.8 GPa, 2 GPa and 2.6 GPa for 0 wt%, 12 wt%, 16 wt% and 20 wt% loading respectively (supplementary information). The shape memory properties were measured by unconstrained strain recovery. It was observed that, with increased filler loading, increasing stress was required to achieve the same strain, while shape recovery improved with increased loading. Complete shape recovery can be observed when Magpol is heated above 86 °C. However, due to increased sample slippage at the grips at higher temperature, the maximum recovery temperature was fixed at 70 °C. At 70 °C there is a small difference in the shape recovery properties of Magpol; increasing loading enables higher shape recovery, EVA 0 wt% filler shows the least recovery.


Magnetic Field Triggered Multicycle Damage Sensing and Self Healing.

Ahmed AS, Ramanujan RV - Sci Rep (2015)

DMA measurement of the Shape memory properties of Magpol with filler concentrations of 0, 12, 16, and 20 wt% over two cycles of unconstrained strain and recovery.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4562241&req=5

f2: DMA measurement of the Shape memory properties of Magpol with filler concentrations of 0, 12, 16, and 20 wt% over two cycles of unconstrained strain and recovery.
Mentions: DMA results (Fig. 2) show that there is not much change in Tg with increased filler loading. The Tg ranges between −25 °C for 0 wt% loading to −20 °C for 20 wt% loading. At −80 °C, there is an increase in the storage modulus with loading. The storage modulus was found to be 1.5 GPa, 1.8 GPa, 2 GPa and 2.6 GPa for 0 wt%, 12 wt%, 16 wt% and 20 wt% loading respectively (supplementary information). The shape memory properties were measured by unconstrained strain recovery. It was observed that, with increased filler loading, increasing stress was required to achieve the same strain, while shape recovery improved with increased loading. Complete shape recovery can be observed when Magpol is heated above 86 °C. However, due to increased sample slippage at the grips at higher temperature, the maximum recovery temperature was fixed at 70 °C. At 70 °C there is a small difference in the shape recovery properties of Magpol; increasing loading enables higher shape recovery, EVA 0 wt% filler shows the least recovery.

Bottom Line: Magpol exhibited a linear strain response upto 150% strain and complete recovery after healing.We have demonstrated the use of this concept in a reusable biomedical device i.e., coated guidewires.Our findings offer a new synergistic method to bestow multifunctionality for applications ranging from medical device coatings to adaptive wing structures.

View Article: PubMed Central - PubMed

Affiliation: School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore.

ABSTRACT
Multifunctional materials inspired by biological structures have attracted great interest, e.g. for wearable/ flexible "skin" and smart coatings. A current challenge in this area is to develop an artificial material which mimics biological skin by simultaneously displaying color change on damage as well as self healing of the damaged region. Here we report, for the first time, the development of a damage sensing and self healing magnet-polymer composite (Magpol), which actively responds to an external magnetic field. We incorporated reversible sensing using mechanochromic molecules in a shape memory thermoplastic matrix. Exposure to an alternating magnetic field (AMF) triggers shape recovery and facilitates damage repair. Magpol exhibited a linear strain response upto 150% strain and complete recovery after healing. We have demonstrated the use of this concept in a reusable biomedical device i.e., coated guidewires. Our findings offer a new synergistic method to bestow multifunctionality for applications ranging from medical device coatings to adaptive wing structures.

No MeSH data available.


Related in: MedlinePlus