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Abstract: As an external stimulus for stimuli‐responsive chromic materials, a magnetic field has the benefits of contactless control, instant action, and ease of integration into electronic devices. Hence, the development of a magnetically responsive photonic crystal provides a new platform for color displays. However, magnetically controlled display systems have been primarily limited to liquid systems of colloidal crystals; their application to solid chromic systems has been difficult because the ordered array structure is fixed by a polymer network. A novel solid magnetochromic photonic hydrogel is developed that enables colorimetric responses to an alternating magnetic field (AMF). This notable magnetochromic performance is attributed to the superior magnetothermal effect of 1D aggregates of magnetic chains fixed in a thermosensitive hydrogel. The AMF‐responsive magnetic hydrogel exhibits excellent stability for repeated use. This study presents a basis for the development of responsive solid materials with new optical effects for future chromatic applications. [ABSTRACT FROM AUTHOR]

ABSTRACT The layer-by-layer (LBL) assembly technique is an attractive method to make functional multilayer thin films and has been applied to fabricate a wide range of materials. LBL materials could improve optical transmittance and mechanical properties if the film components were covalently bonded. Covalently bonded nanocomposite multilayer films were prepared by employing hydrophilic aliphatic polyisocyanate (HAPI) as the reactive component, to react with Laponite and polyvinyl alcohol (PVA). FT-IR spectra suggested that HAPI reacted with Laponite and PVA at ambient temperature rapidly. Ellipsometry measurement showed that the film thickness was in linear growth. The influences of HAPI on the optical, mechanical and thermal properties of the films were investigated by UV-Vis spectroscopy, tensile stress measurement, DSC and TGA. The obtained results showed that the optical transmittance and mechanical strength were enhanced when the film components were covalently bonded by HAPI. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 545-551 [ABSTRACT FROM AUTHOR]