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Smart Machining Processes
6. Electrochromic materials are an imperative part of today’s liquid crystal
display units. Such a material changes its optical properties when an electric current is passed through it.
7. Fullerenes are allotropes of carbon made up of hexagons and pentagons
connected by single and double bonds forming a caged sphere with carbon
atoms at its nodes. Due to its shape, fullerene is highly stable and versatile
in nature.
8. Biomimetic materials are inspired by nature. Their geometric shapes are
very simple yet effective in terms of purposes like strength, camouflage,
water proofing, and mobility. Examples of such materials can be honeycomb structures, coconut tree leaves, bird’s flight, beehive, spider web,
water repellency of fish skin, etc. Their applications range from self-sensing
to self-repairing in buildings.
Hu (2016) characterizes a number of active materials for textile coating, namely
smart and polymeric hydrogels, memory polymers, phase-change materials, colorchange materials, and functional nanomaterials.
Smart or polymeric hydrogels belong to a group of hydrogels that display various
changes under specific external conditions such as temperature, pH, light, salt, and
stress. These materials respond with swelling/collapsing and hydrophilic/hydrophobic changes in shape. Among the hydrogels most commonly used in active coating
are temperature-active hydrogels, where transition temperature is adjusted by additives modifying monomer structure or copolymerization.
Memory polymers are smart materials that can sense thermal, mechanical, electric,
and magnetic stimuli and respond by changing their shape, position, stiffness, and other
static and dynamic characteristics. They have low costs and exhibit good processing
ability and controllable responses, making them even more suitable for industrial production than SMAs. Becoming the most widely applicable smart materials, this group
of memory polymers have developed rapidly in both academic and industrial areas.
Adaptive polymeric particles include nanoparticles and microcapsules of different
chemical and physical parameters, such as morphology, shape, size, light reflection/
diffraction, and solvent ability. Smart materials combined with particle materials
provide beneficial and unique properties to textile coating owing to their tiny forms
and responsive characteristics different from normal particles. The surface properties of nanoparticles are more essential than those of microcapsules and applications of active coating of these particles include self-cleaning textiles, phase-change
microencapsulation textiles, and hydrophilic/hydrophobic textiles (Hu, 2016).
Phase-change materials (PCMs) possess the ability to change their state within
a certain temperature range, absorbing energy during the heating process as phase
changes take place and transferring it to the environment in the phase change range
during a reverse cooling process. The insulation effect reached by the PCM takes
place only during the phase change in a certain temperature range and terminates
when the phase change in all of the PCMs is complete. Hence, this type of thermal insulation is temporary and can be referred to as dynamic thermal insulation
(Mondal, 2008).
Smart Machining Processes
6. Electrochromic materials are an imperative part of today’s liquid crystal
display units. Such a material changes its optical properties when an electric current is passed through it.
7. Fullerenes are allotropes of carbon made up of hexagons and pentagons
connected by single and double bonds forming a caged sphere with carbon
atoms at its nodes. Due to its shape, fullerene is highly stable and versatile
in nature.
8. Biomimetic materials are inspired by nature. Their geometric shapes are
very simple yet effective in terms of purposes like strength, camouflage,
water proofing, and mobility. Examples of such materials can be honeycomb structures, coconut tree leaves, bird’s flight, beehive, spider web,
water repellency of fish skin, etc. Their applications range from self-sensing
to self-repairing in buildings.
Hu (2016) characterizes a number of active materials for textile coating, namely
smart and polymeric hydrogels, memory polymers, phase-change materials, colorchange materials, and functional nanomaterials.
Smart or polymeric hydrogels belong to a group of hydrogels that display various
changes under specific external conditions such as temperature, pH, light, salt, and
stress. These materials respond with swelling/collapsing and hydrophilic/hydrophobic changes in shape. Among the hydrogels most commonly used in active coating
are temperature-active hydrogels, where transition temperature is adjusted by additives modifying monomer structure or copolymerization.
Memory polymers are smart materials that can sense thermal, mechanical, electric,
and magnetic stimuli and respond by changing their shape, position, stiffness, and other
static and dynamic characteristics. They have low costs and exhibit good processing
ability and controllable responses, making them even more suitable for industrial production than SMAs. Becoming the most widely applicable smart materials, this group
of memory polymers have developed rapidly in both academic and industrial areas.
Adaptive polymeric particles include nanoparticles and microcapsules of different
chemical and physical parameters, such as morphology, shape, size, light reflection/
diffraction, and solvent ability. Smart materials combined with particle materials
provide beneficial and unique properties to textile coating owing to their tiny forms
and responsive characteristics different from normal particles. The surface properties of nanoparticles are more essential than those of microcapsules and applications of active coating of these particles include self-cleaning textiles, phase-change
microencapsulation textiles, and hydrophilic/hydrophobic textiles (Hu, 2016).
Phase-change materials (PCMs) possess the ability to change their state within
a certain temperature range, absorbing energy during the heating process as phase
changes take place and transferring it to the environment in the phase change range
during a reverse cooling process. The insulation effect reached by the PCM takes
place only during the phase change in a certain temperature range and terminates
when the phase change in all of the PCMs is complete. Hence, this type of thermal insulation is temporary and can be referred to as dynamic thermal insulation
(Mondal, 2008).