CONDUCTING POLYMERS (CPS) HAVE BECOME ONE OF THE MOST ATTRACTIVE SUBJECTS OF INVESTIGATION IN LAST DECADES. POLYMERIC ANTIMICROBIAL AGENTS HAVE THE ADVANTAGES THAT THEY ARE NONVOLATILE, CHEMICALLY STABLE, AND FIND IT DIFFICULT TO PERMEATE THROUGH THE SKIN OF MAN.CONDUCTING POLYMERS HAVE BECOME ONE OF THE MOST ATTRACTIVE SUBJECTS OF ANTIMICROBIAL POLYMERS INVESTIGATION IN RECENT YEARS.PPY WAS SYNTHESIZED BY CHEMICAL OXIDATIVE POLYMERIZATION OF MONOMER IN THE PRESENCE OF HYDROXYPROPYLCELLULOSE (HPC) AS A STABILIZER AND FECL AS AN OXIDANT. IN FIGURE &NBSP;SEM MICROGRAPH OF PPY IS DEPICTED. AS IT IS EXPECTED PPY SHOWS AN AMORPHOUS MORPHOLOGY WITH UNIFORMLY DISPERSED SPHERICAL PARTICLES WITH AVERAGE DIAMETER OF 50-100 NM AND MAJORITY OF THE PARTICLES ARE <60NM IN DIAMETER. THE ANTIBACTERIAL PROPERTIES WERE MEASURED BY DISK DIFFUSION TECHNIQUE AGAINST GRAM-NEGATIVE BACTERIA; E. COLI (PTCC 1398). FOR DISK DIFFUSION TECHNIQUE, STERILE FILTER PAPER DISKS WITH DIAMETER OF B MM THAT WERE SATURATED WITH PPY SUSPENSION WERE PUT ON THE CENTER OF AGAR PLATES WHICH HAD 200 ML INOCULUMS FAIRLY WELLDISTRIBUTED.THE INHIBITION ZONE WAS MEASURED AFTER 24' H INCUBATION AT 370OC. THE PICTURE DISPLAYED IN FIGURE 2 INDICATE THAT THE ZONES OF INHIBITION FOR THE PPY VERSUS E. COLI IS SIGNIFICANTLY OUTLINED (11-13 MM). THE RESULT SHOWED CLEARLY THAT, PPY STRONGLY INHIBIT THE GROWTH OF WILD-TYPE E. COLI BACTERIA.

THE CONJUGATED POLYMER–METAL COMPOSITES HAVE ATTRACTED MUCH ATTENTION BECAUSE OF THEIR APPLICATIONS IN CHEMICAL, PHYSICAL, MICROELECTRONICS, SUCH AS BIOMEDICINE, ELECTROMAGNETIC SHIELDING. THE PROPERTIES OF THESE SYSTEMS CAN BE EXPECTED TO BE DIFFERENT FROM THOSE OF THE CONJUGATED POLYMERS OR METAL SPECIES, BASED ON THE FACT THAT THE SMALL SIZED PARTICLES ENHANCE THE PROPERTIES WHILE THE POLYMER MATRIX OFFERS FLEXIBLE FUNCTIONALITIES. AMONG THE CONJUGATE POLYMERS, Polypyrrole (PPY) HAS BEEN OF PARTICULAR INTEREST BECAUSE OF ITS ENVIRONMENTAL STABILITY, CONTROLLABLE ELECTRICAL CONDUCTIVITY, AND INTERESTING REDOX PROPERTIES [6]. SILVER NANOPARTICLES HAVE APPLICATIONS IN CONDUCTIVE INKS, CATALYSIS, PHOTONICS, PHOTOGRAPHY, THICK FILM PASTES AND ADHESIVES FOR VARIOUS ELECTRONIC COMPONENTS. IN A TYPICAL EXPERIMENT (1 ML) PYRROLE MONOMER WAS ADDED TO STIRRED AQUEOUS SOLUTION (100 ML) CONTAINING 5G OF FECL3 AND 0.5G OF AG NANOPARTICLES (10-50 NM). AFTER 5HOURS, THE POLYMER WAS FILTERED, AND IN ORDER TO SEPARATE THE OLIGOMERS AND IMPURITIES, THE PRODUCT WAS WASHED SEVERAL TIMES WITH DEIONIZED WATER. IT WAS THEN DRIED AT ROOM TEMPERATURE.A NUMBER OF TECHNIQUES WERE USED TO CHARACTERIZE THE PPY/AG NANOCOMPOSITE INCLUDING FOURIER TRANSFORM INFRARED (FTIR) AND SCANNING ELECTRON MICROSCOPY (SEM). THE FIGURE 1 SHOWS OF SCANNING ELECTRON MICROGRAPH OF PPY/AG. THE FTIR SPECTRA OF PPY/AG NANOCOMPOSITE ARE COMPARATIVELY SHOWN IN FIGURE 2.AS SHOWN IN SEM IMAGE (FIGURE 1), THE SILVER PARTICLES (WHITE SPOTS) ARE WELL ADHERED ON THE PPY SUBSTRATE DUE TO STRONG AFFINITY OF SILVER FOR NITROGEN OF PPY STRUCTURE.

INTRODUCTION: CONDUCTIVE ELECTROACTIVE POLYMERS SUCH AS Polypyrrole (PPY) POSSESS SOME UNIQUE CHEMICAL AND ELECTROCHEMICAL PROPERTIES. THE INSOLUBILITY IN COMMON SOLVENTS AND INFUSIBILITY OF CONDUCTING POLYMERS, IN GENERAL, MAKE THEM POORLY PROCESSABLE EITHER BY SOLUTION TECHNIQUE OR BY MELT PROCESSING METHODS [1, 2]. IMPROVEMENT OF THESE MATERIAL PROPERTIES CAN BE ACHIEVED EITHER BY FORMING COPOLYMERS, COMPOSITES OR BLENDS WITH COMMERCIALLY AVAILABLE POLYMERS OR INORGANIC MATERIALS WHICH OFFER BETTER MECHANICAL AND OPTICAL PROPERTIES, STABILITY AND PROCESSABILITY [3-5].THUS, IN THIS STUDY Polypyrrole/CHITOSANNANOCOMPOSITE WAS PREPARED IN AQUEOUS MEDIA BY USING FERRIC CHLORIDE AS AN OXIDANT.

AN ELECTROCHROMIC MATERIAL IS THE ONE THAT CHANGES COLOR IN A PERSISTENT BUT REVERSIBLE MANNER BY AN ELECTROCHEMICAL REACTION AND THE PHENOMENON IS CALLED ELECTROCHROMISM. CONDUCTING POLYMERS (CPS) ARE FINDING INCREASING USE IN ELECTROCHROMIC APPLICATIONS BECAUSE OF THEIR CATHODIC, ANODIC AND MULTICOLOR CONTROL, EASE IN PROCESSABILITY, FLEXIBILITY, RAPID REDOX SWITCHING, HIGH OPTICAL CONTRAST, AND LONG-TERM STABILITY [1]. THE PHYSICAL MATERIAL PROPERTIES SUCH AS COLOR, CONDUCTIVITY, AND SURFACE ENERGY CAN BE CONTROLLED BY ELECTROCHEMICAL DOPING IN A CP. BY DOPING A CP, NEW ENERGY LEVELS ARE CREATED WITHIN THE BAND GAP DUE TO GENERATION OF POLARONS AND BIPOLARONS IN THE POLYMER BULK [2]. THE ELECTROCHROMIC PROPERTIES OF CPS HAVE BECAME OF GREAT IMPORTANCE IN MODERN REVERSIBLE ELECTRO-SWITCHING OPTICAL DESIGN OF POLYMER BASED OPTICAL SENSORS AND DEVICES. IN THIS PAPER, WE REPORT ON THE ELECTROCHEMICAL PREPARATION OF THE CONDUCTING Polypyrrole (PPY) SYNTHESIZED WITH ENTRAPPED HEPARIN (HEP) ANIONS. HEPARIN, A WIDELY USED ANTICOAGULANT, IS A HIGHLY SULFATED LINEAR NATURAL POLYSACCHARIDE [3]. THE ELECTROCHROMIC PROPERTIES OF Polypyrrole FILM ARE DIFFICULT TO EXPLOIT DUE TO THE DISSATISFACTORY STABILITY. WE HAVE CHOSEN HEP AS THE DOPING ANION SINCE ITS POLYANIONIC NATURE PREDICTS THAT IT WOULD INCREASE THE STABILITY OF PPY FILM. THE HEP-DOPED PPY WAS ELECTROCHEMICALLY SYNTHESIZED ON A FLUORINE DOPED TIN OXIDE FTO/GLASS ELECTRODE IN AQUEOUS SOLUTION. THE RESULTANT POLYMER WAS CHARACTERIZED VIA ELECTROCHEMICAL AND SPECTROELECTROCHEMICAL METHODS. THE SPECTROELECTROCHEMICAL ANALYSIS REVEALED THE PPY-HEP HAS DISTINCT ELECTROCHROMIC PROPERTIES WITH RESPECT TO THE PPY. POLYANIONDOPED POLYMER EXHIBITED A SWITCHING TIME OF LESS THAN 1.5 S AND THE MAXIMUM TRANSMITTANCE CONTRAST (DT%) IS 48% AT 800 NM. IN ADDITION PRESENCE OF HEP CAUSES DRASTIC ENHANCEMENT OF ELECTRO-OPTICAL STABILITY OF PPY. THE INTRODUCTION OF HEP POLYANION CAN LEAD TO ENHANCE THE FORMATION OF AN ORDERED PPY-BASED FILM WHICH CAN BE REASON FOR IMPROVEMENT OF STABILITY.