Study of chemical synthesis conditions of conducting polymer polypyrrole

Abstract

U radu je provedeno ispitivanje uvjeta sinteze vodljivog polimera polipirola s ciljem da se postigne odgovarajuća struktura koja je fotoosjetljiva u širem dijelu vidljivog dijela sunčeva spektra. Tijekom sinteze polipirola (PPy) uzorcima je mijenjan udio oksidansa (FeCl3) u odnsou na udio monomera pirola, odnos monomer : oksidans bio je: 1:1; 1:1,5; 1:2; 1:5; vrijeme sinteze bilo je 90 i 180 min, dok je tempratura održavana konstantnom, 5 °C. Za svaki sintetiziran uzorak određen je stupanj konverzije monomera, a potom su uzorci karakterizirani infracrvenom spektroskopijom s Fourierovom transformacijom (FTIR). Provedena je također njihova fotokatalitička validacija UV/VIS spektrofotometrom, pomoću kojeg se mjerila efikasnost razgradnje organskog azo bojila (Reactive Red 45) kao onečišćivaća vode. Iz rezultata istraživanja uvjeta sinteze vodljivog polimera polipirola se može zaključiti da promjena uvjeta sinteze znatno utječe na stupanj konverzije i strukturu molekula pirola, kao i na veličinu molekulskih masa što je vidljivo iz različitog fotokatalitičkog djelovanja. Iz rezultata fotokatalitičke razgradnje može se zaključiti da s vremenom fotokatalitičke razgradnje obezbojenje sporo raste kad je proces kataliziran s čistim PPy. Rezultati također ukazuju da je proces adsorpcije bojila na PPy katalizatore značajan.In this work research of synthesis conditions of polypyrrole conductive polymer was carried out in order to achieve an appropriate structure, which is photosensitive in the wider part of the visible solar spectrum. During the synthesis of polypyrrole (PPY) samples fraction of oxidant (FeCl3) was altered in comparison to fraction of pyrrole monomer, the ratio of monomer: oxidant was: 1: 1; 1: 1.5; 1: 2; 1: 5, the time of synthesis was 90 and 180 min, while the temperature was maintained constant at 5 ° C. For each synthesized sample degree of conversion of the monomer was determined, and then the samples were further characterized by infrared spectroscopy with Fourier transform (FTIR). The validation of their photocatalytic activity was carried out by UV / VIS spectrophotometer, by measuring the efficiency of decomposition of the organic azo dyes (Reactive Red 45) that were used as water pollutant. From the results of the synthesised conducting polymer polypyrrole can be concluded that the change in the conditions of synthesis greatly affect the degree of conversion and the structure of the molecule is pyrrole, as well as the size of the molecular weight, which is demonstrated by the different photocatalytic activity. From the results of photocatalytic degradation of RR45 can be concluded that with time of photocatalytic degradation discoloration is growing slow when PPy was used as photocatalyst, but the process of adsorption of dyes on PPy photocatalysts was significant