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Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

ABSTRACT: Tunable and durable photochromic materials are a rapidly expanding area of interest, with applications ranging from biomedical devices to industrial-fields. Here we examine electrospun poly (methacrylic acid) PMAA nanofibers covalently modified with the highly photochromic molecule, spiropyran (SP) or a derivate SP which is firstly coupled to a cyclodextrin molecule (?CDSP). The photochromic properties of the starting materials and of the nanofibers were investigated. ?CDSP, PMAASP and PMAA-?CDSP polymers exhibited a reverse photochromism. The kinetic results revealed a faster isomerization process for the ?CDSP molecule, than that for the PMAA-?CDSP and for the PMAASP, the slowest one. The fastest isomerization is attributed to the presence of a large number of hydroxyl groups of the ?CD which stabilizes the merocyanine form via hydrogen bonding, and the slowest isomerization is related to the PMAA chain structure that stabilizes the spiropyran form. Thus, combining the PMAA and ?CD properties the photo-isomerization can be modulated. The photoreversibility of this material was verified by UV-visible measurements cycling visible and UV light. Infrared spectroscopy and water contact angle were used for the nanofiber surface characterization, demonstrating the presence of the spiropyran on the mats surface and also showing a minimal effect on nanofiber size and shape when compared to PMAA fiber.

SUBMITTER: De Sousa FB

PROVIDER: S-EPMC5307972 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

De Sousa Frederico B FB Guerreiro João D T JD Ma Minglin M Anderson Daniel G DG Drum Chester L CL Sinisterra Rubén D RD Langer Robert R

Journal of materials chemistry 20100928 44

Tunable and durable photochromic materials are a rapidly expanding area of interest, with applications ranging from biomedical devices to industrial-fields. Here we examine electrospun poly (methacrylic acid) PMAA nanofibers covalently modified with the highly photochromic molecule, spiropyran (SP) or a derivate SP which is firstly coupled to a cyclodextrin molecule (βCD<sub>SP</sub>). The photochromic properties of the starting materials and of the nanofibers were investigated. βCD<sub>SP</sub> ...[more]

PMID: 28210069

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Dataset Information

Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

Publications

Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

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