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Effect of end group content on photochromic behavior of spiropyran in polycaprolactone–poly(ethylene succinate) blends

“…The equilibrium between the spiropyran and the merocyanine is shifted toward the colored species with increasing the solvent polarity. 28,29 Similar behavior has also been reported by using 11 and polycaprolactone (PCL) instead of polystyrene (PS). 19 The more polar substrate shifts the absorbance to the red wavelength region.…”

“…9 The use of applicable polymers that are effective in protecting spiropyrans and provide stability against degradation without reducing their photochromic activity is a crucial factor. The photochromic behavior of spiropyrans in polymer films is of increasing interest [10][11][12][13][14][15][16] despite the fact that their photocoloration rate decreases compared with that of liquid solutions, after the dispersion into the polymer matrix. Also, the number of cycles in which the photochromic systems undergo a reversible transformation is limited because of photodegradation processes.…”

Photo‐Responsive Polymeric Structures Based on Spiropyran

“…Since their discovery, photochromic spiropyrans have been incorporated into various materials i.e. surface bound monolayers [7,[11][12][13] , Langmuir monolayers [14] , Langmuir Blodgett films [14] , polymeric brushes [9,[15][16][17] , photocontrollable surfactants [18] , liquid crystalline materials [19] , polymeric matrices [8,15,16,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] , organic/inorganic hybrid systems [37] , colloidal particles [17,38] , ionic liquids [39][40][41][42][43] and initiators for radical polymerisations [44] .…”

Fabrication and photochromic properties of Forcespinning® fibers based on spiropyran-doped poly(methyl methacrylate)

“…The maximum absorbance of the PMC-form in lms based on non-polar matrices appears at 600 nm, whereas the maximum absorbance in lms based on polar matrices (such as PMMA) is with the absorption peak normally seen in PMMA lms. 24 In polar matrices, the PMCform is predominantly comprised of charge-localized zwitterionic structures that are stabilized in such matrices. Nadolski et al have suggested that the singlet ground state is more polar than the singlet excited state, 25 therefore, the PMC-form is stabilized against external heating in polar matrices, which results in a short-wavelength shi (that is, a hypsochromic shi).…”