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Conducting polymers by ankit gupta

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Polyacetylene  Organic polymers that conduct electricity are called conducting polymers.  Such compounds may have metallic conductivity or can be semiconductors.  The biggest advantage of conductive polymers is their processability, mainly by dispersion.  In 1970 H.shirakawa reported high molecular weight polyacetylene film by passing dry acetylene gas over Ziegler- Natta catalyst of titanium tetrabutoxide triethyl aluminium in toluene at -78℃.  It was obtained on the surface of the catalyst.  And also in the two forms known as cis and trans. (1) Is cis polyacetylene. (2) Is trans polyacetylene.  The role of a dopant is to either add or remove electrons to the polymer.  It is of two kinds:  (1) Oxidative or p-doping. (2) Reductive or n-doping.  The oxidizing agents for P-doping are like iodine vapours,I dissolved in CCl , ₂ ₄ HBF , HClO , Br etc.₄ ₄ ₂  (CH) n (CH)→ n I⁺ ₃⁻  The conduction in this type of doping increases up to 10⁵ s/cm.  The reducing agents for n-doping are like Na metal ,FeCl , lithium metal ₂ ,sodium naphthalide etc.  (CH) n → (CH) Na⁻ ⁺  Negative charge resonates throughout the chain and transferred to neighbouring chains through Na ⁺ during conduction.  For making rechargeable batteries.  Used as sensors for phenol , O etc at ₂ low concentrations.  For manufacture of transistors ,LEDs, lasers and solar cells.  In telecommunication systems  In the construction of photovoltaic cells. Solar cell Light-emitting diodes Shield for computer screen against electromagnetic "smart" windows radiation . Polyacetylene  Organic polymers that conduct electricity are called conducting polymers.  Such compounds may have metallic conductivity or can be semiconductors.  The biggest advantage of conductive polymers. conductive polymers is their processability, mainly by dispersion.  In 1970 H.shirakawa reported high molecular weight polyacetylene film by passing dry acetylene gas over Ziegler- Natta catalyst

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