Thermochromic transition analysis of elastomer prepared from azo dye-siloxane blend

• Published in: Materials chemistry and physics 2020-01, Vol.240, p.122297, Article 122297
• Main Authors: Soreño, Zhander Vohr, Puguan, John Marc C., Kim, Hern
• Format: Article
• Language: English
• Subjects: Azobenzene; Commercialization; Dye; Dyes; Elastomer; Elastomers; Iodine; Methyl red; pH-indicator; Polydimethylsiloxane; Room temperature; Solid-state; Spin coating; Thermochromism; Vulcanization
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2019.122297

In the search for portable thermochromic material, this work presented a simple preparation of a thermochromic elastomer using a commercialized dye indicator. The material was prepared using polydimethylsiloxane as a polymer matrix and methyl red as a thermochromic dye via room-temperature vulcanization of spin-coated glass slides. A sample was heated at 10 °C interval and was shown to have a reversible visual thermochromic behavior (orange ↔ yellow). The presence of saturated iodine to the system improved the thermochromic behavior (gray ↔ olive green ↔ yellow) at ≈50 °C and ≈80 °C. Furthermore, this work used graphical and L*a*b* analysis in aiming to correct the imperfection of the naked eye in defining colors. Thermochromic properties of methyl red – siloxane elastomer containing (a) 0 mM and (b) 5 mM iodine concentration. [Display omitted] •A thermochromic elastomer was successfully prepared by simple blending of methyl red dye and polydimethylsiloxane prepolymer.•Thermochromic material exhibiting reversible color switching.•Least visual-dependent thermochromic transition time.•Iodine improves thermochromic transition property.•Thermochromic transition using graphical analysis supported by L*a*b* analysis.