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PEDOT-TMA
Poly(3,4-ethylenedioxythiophene)-tetramethacrylate or PEDOT-TMA is a p-type conducting polymer based on 3,4-ethylenedioxylthiophene or the EDOT monomer. It is a modification of the PEDOT structure. Advantages of this polymer relative to PEDOT (or PEDOT:PSS) are that it is dispersible in organic solvents, and it is non-corrosive. PEDOT-TMA was developed under a contract with the National Science Foundation, and it was first announced publicly on April 12, 2004. The trade name for PEDOT-TMA is Oligotron. PEDOT-TMA was featured in an article entitled "Next Stretch for Plastic Electronics" that appeared in Scientific American in 2004. The U.S. Patent office issued a patent protecting PEDOT-TMA on April 22, 2008. PEDOT-TMA differs from the parent polymer PEDOT in that it is capped on both ends of the polymer. This limits the chain-length of the polymer, making it more soluble in organic solvents than PEDOT. The methacrylate groups on the two end-caps allow further chemistry to o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PEDOT
Poly(3,4-ethylenedioxythiophene) (PEDOT or PEDT; ''IUPAC'' name poly(2,3-dihydrothieno ,4-''b''1,4]dioxane-5,7-diyl)) is a conducting polymer based on 3,4-ethylenedioxythiophene or EDOT. It was first reported by Bayer AG in 1989. Polymer PEDOT possesses many advantageous properties compared to earlier conducting polythiophenes like 3-alkylthiophenes. For example, the polymer is optically transparent in its conducting state and has high stability, moderate band gap, and low redox potential. Its major disadvantage is its poor solubility, which is partly circumvented by use of composite materials such as PEDOT:PSS and PEDOT-TMA. The polymer is generated by oxidation. The process begins with production of the radical cation of EDOT monomer, 2H4O2C4H2Ssup>+. This cation adds to a neutral EDOT followed by deprotonation. The idealized conversion using peroxydisulfate is shown: :n C2H4O2C4H2S + n (OSO3)22− → 2H4O2C4Ssub>n + 2n HOSO3− Polymerization is usually conduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. This organic layer is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, and portable systems such as smartphones and handheld game consoles. A major area of research is the development of white OLED devices for use in solid-state lighting applications. There are two main families of OLED: those based on small molecules and those employing polymers. Adding mobile ions to an OLED creates a light-emitting electrochemical cell (LEC) which has a slightly different mode of operation. An OLED display can be driven with a passive-matrix (PMOLED) or active-matri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conducting Polymer
Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The biggest advantage of conductive polymers is their processability, mainly by dispersion. Conductive polymers are generally not thermoplastics, ''i.e.'', they are not thermoformable. But, like insulating polymers, they are organic materials. They can offer high electrical conductivity but do not show similar mechanical properties to other commercially available polymers. The electrical properties can be fine-tuned using the methods of organic synthesis and by advanced dispersion techniques. History Polyaniline was first described in the mid-19th century by Henry Letheby, who investigated the electrochemical and chemical oxidation products of aniline in acidic media. He noted that reduced form was colourless but the oxidized forms were deep blue. The first highly-conductive org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphene Oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry (the measurable relationship between reactants and chemical equations of a equation or reaction) Oxides are extraordinarily diverse in terms of stoichiometries and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnshaw, A. (1997). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylate Esters
In organic chemistry, a carboxylate is the conjugate base of a carboxylic acid, (or ). It is an ion with negative charge. Carboxylate salts are salts that have the general formula , where M is a metal and ''n'' is 1, 2,...; ''carboxylate esters'' have the general formula (or ). R and R′ are organic groups; R′ ≠ H. Synthesis Carboxylate ions can be formed by deprotonation of carboxylic acids. Such acids typically have p''K''a of less than 5, meaning that they can be deprotonated by many bases, such as sodium hydroxide or sodium bicarbonate. :RCOOH + NaOH -> RCOONa + H2O Resonance stabilization of the carboxylate ion Carboxylic acids easily dissociate into a carboxylate anion and a positively charged hydrogen ion (proton), much more readily than alcohols do (into an alkoxide ion and a proton), because the carboxylate ion is stabilized by resonance. The negative charge that is left after deprotonation of the carboxyl group is delocalized between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensors
A sensor is a device that produces an output signal for the purpose of sensing a physical phenomenon. In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends the information to other electronics, frequently a computer processor. Sensors are always used with other electronics. Sensors are used in everyday objects such as touch-sensitive elevator buttons ( tactile sensor) and lamps which dim or brighten by touching the base, and in innumerable applications of which most people are never aware. With advances in micromachinery and easy-to-use microcontroller platforms, the uses of sensors have expanded beyond the traditional fields of temperature, pressure and flow measurement, for example into MARG sensors. Analog sensors such as potentiometers and force-sensing resistors are still widely used. Their applications include manufacturing and machinery, airplanes and aerospace, cars, medicine, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transparent Electrodes
Transparency, transparence or transparent most often refer to: * Transparency (optics), the physical property of allowing the transmission of light through a material They may also refer to: Literal uses * Transparency (photography), a still, positive image created on a transparent base using photochemical means * Transparency (projection), a thin sheet of transparent material for use with an overhead projector * Electromagnetically induced transparency, an effect in which a medium that is normally opaque is caused to become temporarily transparent * Pentimento, an alteration in a painting, often revealed with growing transparency in paints with age Animals and plants * Transparent goby, a fish species of the family Gobiidae * White Transparent, a cultivar of apple which is usually used for cooking due to its sharp taste Arts, entertainment, and media Music Groups and labels * Transparency (record label), a North American music publisher * Transparent (band), a rock band from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conductive Polymers
Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The biggest advantage of conductive polymers is their processability, mainly by dispersion. Conductive polymers are generally not thermoplastics, ''i.e.'', they are not thermoformable. But, like insulating polymers, they are organic materials. They can offer high electrical conductivity but do not show similar mechanical properties to other commercially available polymers. The electrical properties can be fine-tuned using the methods of organic synthesis and by advanced dispersion techniques. History Polyaniline was first described in the mid-19th century by Henry Letheby, who investigated the electrochemical and chemical oxidation products of aniline in acidic media. He noted that reduced form was colourless but the oxidized forms were deep blue. The first highly-conductive organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Semiconductors
Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation. General properties In molecular crystals the energetic separation between the top of the valence band and the bottom conduction band, i.e. the band gap, is typically 2.5–4 eV, while in inorganic semiconductors the band gaps are typically 1–2 eV. This implies that they are, in fact, insulators rather than semiconductors in the conventional sense. They become semiconducting only when charge carriers are either injected from the electrodes or generated by intentional or unintentional doping. Charge carriers can also be generated in the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Polymers
A polymer (; Greek ''poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meaning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(methyl Methacrylate)
Poly(methyl methacrylate) (PMMA) belongs to a group of materials called engineering plastics. It is a transparent thermoplastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Plexiglas, Acrylite, Astariglas, Lucite, Perclax, and Perspex, among several others ( see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to glass. It can also be used as a casting resin, in inks and coatings, and for many other purposes. Although not a type of familiar silica-based glass, the substance, like many thermoplastics, is often technically classified as a type of glass, in that it is a non-crystalline vitreous substance—hence its occasional historic designation as ''acrylic glass''. Chemically, it is the synthetic polymer of methyl methacrylate. It was developed in 1928 in several different laboratories by many chemists, such as William Chalmers, Otto Röhm, and Walter Bauer, and first brou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
