Chameleonic materials

Chromism is the ability of a material to change its colour according to a stimulus. Chromic materials might also be called chameleonic materials , due to their ability to adapt to their environment [34]. The types of chromism are defined after the different stimuli that cause their change, such as ... 

Additionally, the film formation properties and outstanding mechanical properties of aramids make these polymers suitable for the production of organic light emitting diodes (OLEDs), and specifically polymer hght emitting diodes (PLEDs). Despite this, classical condensation polymers are rarely studied for these applications. Moreover, some luminescence materials also show electrochromism (EC), a phenomenon in which materials exhibit a reversible change in optical properties when they are oxidized and reduced. Electrochromic materials are now been exploited in diverse applications such as mirrors, displays, windows, and earth-tone chameleon materials [95]. 

Chromic materials are the general term referring to materials, which their eolor changes by the external stimulus. Due to color changing properties, chromic materials are also ealled chameleon materials. This eolor ehanging phenomenon is caused by the external stimulus and... 

We called this material the chameleon TPE. This material represents a new concept in material science entropy-driven TPE (ETPE). 

Whereas in L Air du Temps it is the woody-iris character of the methyl ionone that develops in combination with the vetiveryl acetate, in Paris it forms the basis of a violet accord, with Iso E Super as the woody note. Iso E Super, one of the most important of the newer synthetics, is another chameleon-type product combining woody and amber aspects with some of the character of methyl ionone. Used in Paris as part of the L Air du Temps structure, it forms a natural link between the other materials and the violet accord. 

Although ceramics, as processed inorganic materials, are widely used today by humankind, there are only a half-dozen specific ceramic materials that dominate the different applications. Among similar materials, the perovskites take special place since, with some skilled chemical manipulation, they are able to produce an incredibly wide array of phases with totally different functions. Infact, the perovskites have been dubbed inorganic chameleons, as they display a rich diversity of chemical compositions and properties. 

Greer, A. Lindsay and Mathur, N. (2005). Materials science Changing face of the chameleon. Nature, 437(7063) 1246-1247. 

Only several of the chromogenic phenomena cited in Figure 1 will be briefly discussed below because of space limitation. Recent advances in nearly all of these areas can be foimd in the following chapters of this book. Thermochromism, for example, occurs widely in many n- and o-conjugated polymers and thermochromic polymers are discussed in some prior reviews (1-3, 8). We conclude from our review of the literature that die development of chameleon-like intelligent materials is feasible and can be facilitated by further advances in multifunctional chromogenic polymers. 

Aggregation behavior has also been reported for a number of lizard species (for review see Mason 1992). During the breeding season male chameleons (Chameleo chameleo) aggregate but still appear to maintain territories (Ogilvie 1966). These territories may be maintained by chemical cues rubbed onto the substrate from a temporal pouch. These glands secrete an odoriferous material. 

Special-effect powders can be achieved through the blending of different materials and using different apphcation techniques (38). Powder effects can range from translucents, wrinkles and veins, and multiple colors, to chameleon finishes that appear to change color. Through the use of controlled incompatibil-... 

Indeed, what is considered today to be a key advantage of such plastics was originally seen as a serious drawback. While each different natural substance seemed to be suited to only one or at most a few uses, Bakelite could serve many different purposes, and was used to make combs, hair slides, collars, buttons, telephones and radios, to cite only a few of its better-known applications. Furthermore, the possibility of dyeing Bakelite meant that it could be given the appearance of a variety of different materials, such as tortoiseshell, amber, coral, marble, jade or onyx. Like its polyvalence, its chameleon-like ability to take on different colours devalued Bakelite in the eyes of the public, as it was perceived as a clear indication of the radical inferiority of the artificial substitute with respect to original, natural materials. 

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