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http://dx.doi.org/10.1080/10587259708036145

has been cited by the following article:

• TITLE: Characterization of Spirooxazine and Spiropyran Hosted in Poly(Methyl Methacrylate) for Germicidal UV Source Indicator Application

  AUTHORS: Julien Bonefacino, Ming-Leung Vincent Tse, Chi-Fung Jeff Pun, Xin Cheng, Wing Kin Edward Chan, Arjen Boersma, Hwa-Yaw Tam

  KEYWORDS: UV Indicator; Water Disinfection; Photochromism; Polymer

  JOURNAL NAME: Optics and Photonics Journal, Vol.3 No.7A, November 27, 2013

  ABSTRACT: A characterization of photophysical properties of 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3’-[3H]naphtha[2,1-b] [1,4]oxazine] (spirooxazine) and1’,3’-dihydro-1’,3’,3’-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2’-(2H)-indole] (spiropyran) compounds hosted in poly(methyl methacrylate) (PMMA) was carried out. The parameters which influenced the photochromic behavior of both compounds were investigated. After ultraviolet (UV) irradiation, it was demonstrated that the temperature was the dominant factor which influenced the deactivation of both materials. For spiropyran, it was demonstrated that the process could be photo-induced with a certain wavelength which we have specified in this manuscript. It was also found that X-Ray did not affect the photo physical properties of spirooxazine and spiropyran. Finally, both materials could be used as low-cost germicidal UV indicators.