{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T06:46:02Z","timestamp":1768718762608,"version":"3.49.0"},"reference-count":23,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,6,15]],"date-time":"2017-06-15T00:00:00Z","timestamp":1497484800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, thermochromic photonic gels were fabricated using 2-hydroxyethyl methacrylate (HEMA) as a hydrogel building block, and 4-Acryloyl morpholine (ACMO) and N-isopropylacrylamide (NIPAAM) as thermoresponsive monomers with different critical solution temperature behaviors. Rapid photopolymerization of opal-templated monomer mixtures of varying ACMO contents formed five individual thermochromic inverse opal photonic gels integrated on a single substrate. With temperature variation from 10 \u00b0C to 80 \u00b0C, the changes in reflective colors and reflectance spectra of the respective thermochromic gels were noted, and \u03bbpeak changes were plotted. Because NIPAAM exhibits a lower critical solution temperature (LCST) at 33 \u00b0C, the NIPAAM-only gel showed a steep slope for d\u03bbpeak\/dT below 40 \u00b0C, whereas the slope became flatter at high temperatures. As the ACMO content increased in the thermochromic gel, the curve of d\u03bbpeak\/dT turned out to be gradual within the investigated temperature range, exhibiting the entire visible range of colors. The incorporation of ACMO in NIPAAM-based thermochromic gels therefore enabled a better control of color changes at a relatively high-temperature regime compared to a NIPAAM-only gel. In addition, ACMO-containing thermochromic gels exhibited a smaller hysteresis of \u03bbpeak for the heating and cooling cycle.<\/jats:p>","DOI":"10.3390\/s17061398","type":"journal-article","created":{"date-parts":[[2017,6,15]],"date-time":"2017-06-15T10:07:33Z","timestamp":1497521253000},"page":"1398","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Tunable Temperature Response of a Thermochromic Photonic Gel Sensor Containing N-Isopropylacrylamide and 4-Acryloyilmorpholine"],"prefix":"10.3390","volume":"17","author":[{"given":"Hwanam","family":"Kye","sequence":"first","affiliation":[{"name":"Department of Chemistry, Sejong University, 209 Neungdong-ro, Gwngjin-gu, Seoul 05006, Korea"}]},{"given":"Young","family":"Koh","sequence":"additional","affiliation":[{"name":"Engain Co. Ltd. Korea Bio Park BLD C-201, Seongnam 13488, korea"}]},{"given":"Youkyung","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Sejong University, 209 Neungdong-ro, Gwngjin-gu, Seoul 05006, Korea"}]},{"given":"Sung","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Sejong University, 209 Neungdong-ro, Gwngjin-gu, Seoul 05006, Korea"}]},{"given":"Hyunjung","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Advanced Materials Engineering, Kookmin University, 77 Jeongneung-ro, Seongbuk-gu, Seoul 02707, Korea"}]},{"given":"Wonmok","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Sejong University, 209 Neungdong-ro, Gwngjin-gu, Seoul 05006, Korea"},{"name":"Engain Co. Ltd. Korea Bio Park BLD C-201, Seongnam 13488, korea"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,15]]},"reference":[{"key":"ref_1","unstructured":"Sanchez, I.C., and Stone, M.T. 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