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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

Strain sensing in Magpol.(A) Color change due to plastic deformation observed under UV light @ 377 nm. Deformed regions are deep blue , undeformed material is bluish green. (B) Photoluminescent spectra of Magpol shows the change in the relative heights of the peaks at 425 and 515 nm, which indicate the original colour and colour after straining respectively; The peak at 515 nm becoming more pronounced with increasing strain. (C) Sensitivity of Magpol to a range of strain values measured by the relative change in intensity of 425 and 515 nm peaks as a function of % strain.
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f3: Strain sensing in Magpol.(A) Color change due to plastic deformation observed under UV light @ 377 nm. Deformed regions are deep blue , undeformed material is bluish green. (B) Photoluminescent spectra of Magpol shows the change in the relative heights of the peaks at 425 and 515 nm, which indicate the original colour and colour after straining respectively; The peak at 515 nm becoming more pronounced with increasing strain. (C) Sensitivity of Magpol to a range of strain values measured by the relative change in intensity of 425 and 515 nm peaks as a function of % strain.

Mentions: Photoluminescent (PL) measurements were conducted to investigate the correlation between the shape memory effect and the chromic properties of Magpol. The 20 wt% Magpol was deformed at room temperature until failure (Fig. 3). The emission spectrum in the center of the deformation region was measured for each strain value. Upon plastic deformation the chromophore aggregates (IE) (515 nm) exhibited distinct changes in the absorption band compared to the monomeric species (IM) (475 nm). There is an almost linear decrease in the IE/IM ratio up to 150% strain, followed by a slower decrease until failure.


Magnetic Field Triggered Multicycle Damage Sensing and Self Healing.

Ahmed AS, Ramanujan RV - Sci Rep (2015)

Strain sensing in Magpol.(A) Color change due to plastic deformation observed under UV light @ 377 nm. Deformed regions are deep blue , undeformed material is bluish green. (B) Photoluminescent spectra of Magpol shows the change in the relative heights of the peaks at 425 and 515 nm, which indicate the original colour and colour after straining respectively; The peak at 515 nm becoming more pronounced with increasing strain. (C) Sensitivity of Magpol to a range of strain values measured by the relative change in intensity of 425 and 515 nm peaks as a function of % strain.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f3: Strain sensing in Magpol.(A) Color change due to plastic deformation observed under UV light @ 377 nm. Deformed regions are deep blue , undeformed material is bluish green. (B) Photoluminescent spectra of Magpol shows the change in the relative heights of the peaks at 425 and 515 nm, which indicate the original colour and colour after straining respectively; The peak at 515 nm becoming more pronounced with increasing strain. (C) Sensitivity of Magpol to a range of strain values measured by the relative change in intensity of 425 and 515 nm peaks as a function of % strain.
Mentions: Photoluminescent (PL) measurements were conducted to investigate the correlation between the shape memory effect and the chromic properties of Magpol. The 20 wt% Magpol was deformed at room temperature until failure (Fig. 3). The emission spectrum in the center of the deformation region was measured for each strain value. Upon plastic deformation the chromophore aggregates (IE) (515 nm) exhibited distinct changes in the absorption band compared to the monomeric species (IM) (475 nm). There is an almost linear decrease in the IE/IM ratio up to 150% strain, followed by a slower decrease until failure.

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