9 Stimuli-responsive smart and functional textiles

The definition of stimuli as per biology is an external source of energy or some means that force to react to an organ or part of an organ. Cold or hot sensation, any external mechanical force applied upon, mosquito bites, smell, touch, etc. are a few examples of stimuli, and our body instantly reacts when any of these stimuli are acted upon. Similarly, any smart polymeric materials which can react, sense, and respond to the applied external stimuli such as temperature, light, presence of any chemical agent, moisture, pH, or presence of electric and magnetic fields, etc. are called stimuli-responsive polymeric materials. They are also called smart materials. Any textile structure made using the stimuli-responsive polymer or above-mentioned smart material is called stimuli- responsive textile. As the name suggests, it is the new addition of smart textiles and one of the most emerging areas, and they are gaining much scientific interest among the research community and industry to improve or impart smart functionalities into textiles. Photochromic, solvatochromic, aesthetic appeal, comfort, electrochromic, ionochromic, piezochromic, textile soft display, smart controlled drug release, pH-responsive, chemichromic, mechanochromic, fantasy design with colour changing, wound monitoring, smart wetting properties, and protection against extreme variations in environmental conditions, phase change, etc. are few to name with of various smart functionalities which can be imparted by using stimuli-responsive textiles. Dyeing, printing, finishing (coating or lamination) and dope dyeing (inherent properties), and composite structures are a few methods available for imparting stimuli-responsive properties into textiles.