as dye 1 with n being 1 dye 1 shown above is a photochromic backbone polymer that contains 7 8 repeat units degree of polymerization dp 7 8 while dye 2 shown above is a photochromic molecule with a specifically chosen end group stellacci f bertarelli c toscano f gallazzi m c zerbi g chem phys lett 302 5 6 563 570 1999 u201c stellacci u201d dye 3 is the same chemical formula as dye 1 with n being 1 to prepare the electrospun fibers pmma and either dye1 or dye2 are dissolved in chcl 3 using the specific concentrations shown in table 1 the resultant dye1 or dye2 pmma solution is then electrospun using established processing protocols the specific parameters used for the first set of experiments described below are summarized in table 1 in table 1 the conditions used for the electrospinning of the photochromic fibers are as follows concentration is in wt voltage is the potential of the syringe nozzle relative to the grounded target speed rate is the amount of solution provided to the syringe nozzle h t is the relative humidity and temperature at the time the electrospun fibers were produced as a result of electrospinning the dye pmma solutions fibers whose diameters range between 1 and 10 microns are produced depending on the concentration of pmma in chcl 3 under other conditions fibers smaller and bigger than this range have been produced by the electrospinning process as described in megelski u201c stephens u201d j s stephens j f rabolt.