| This work is composed of two parts: the first is about doping and conductive properties of polydienes and the second is about synthesis and property studies of polypyrrole's copolymer. In the first part, the high trans-1,4-polybutadienes were prepared by lanthanum naphthenate, dibutyl magnesium and THF catalytic system (La(naph)3-(n-Bu)2Mg-THF). The polymer's trans-1,4-content is over 96 %, the molecular weight is about 5000-15000, the distribution of molecular weight is 1.2 and the melt point is 80癈. When La(naph),:(n-Bu):Mg:THF is 1:10:12, temperature is 50癈 and solvent is hydrocarbon, the activity of polymerization is the best.The conductivity of trans-1,4-polybutadiene prepared by rare earth catalyst can be enhanced about 10 orders of magnitude via doped with iodine and reaches 10" S.cm"1. This value is 2 orders of magnitude more than the values reported |311. The relationship between conductivity and temperature indicates that the transport of charge in polydiene is fit on three-dimension variable-range hopping. Moreover, the studies showed that molecular weight of polydiene has no effect on conductivity. According to the FTIR and ultraviolet/ visible spectrum, the conjugated sequence formed in chain of polydiene during I2-doping.The electrochemical properties of I2-doped polydienes were studied for the first time and the results showed they have good and reversible electrochemical activities. When the range of potential is from 0 to 1 V in 1 M NaCl aqueous solution, the cyclic voltammetry indicates that there are two groups of redox peaks, which represent doping-undoping process of Cl~ and iodine's redox respectively. The doping-undoping process of Cl~ is controlled by polymer electrode/solution diffusion and iodine's redox is controlled by kinetics, according to AC impedance measurement. Some physical parameters (Cdl -. Rcl) and general impedance behaviors were discussed too.In the second part, the studies focused on syntheses and properties of polypyrrole's copolymer. The pyrrole (Py) and vinyl n-butyl ether (VBE) copolymer is prepared by electrochemical polymerization for the first time and the content of VBE in copolymer can reach 40 % (molar percent). The higherpotential of synthesis is, the copolymer contains more pyrrole units and vice versa. Moreover, the cyclic voltammetry shows that the copolymer has no reversible electrochemical activity.The pyrrole (Py) and propylcne oxide (PO) copolymer is prepared by electrochemical polymerization for the first time. The composition of copolymer varies from 0 to 60 % (molar percent) at different synthesis conditions. The ITO working electrode is better than Pt electrode for preparing higher PO content copolymer. The polar and weakly nucleophilic solvents, such as Nitromethane, 1.2-dichloroethane, are in favor of Py and PO copolymerization. At potential range from -1 V to 1.5 V, in nitromethane containing 0.05 M Bu4NBF_,. the cyclic voltammetry of Py-PO copolymer indicates that there is a pair of redox peak, which represents doping-undoping process of BF4~ in copolymer. With the technology of impedance measurement, charge transfer resistance (RJ, double layer capacitance (Cdl) and general impedance behavior of Py-PO copolymer were also discussed.Copolymer of pyrrole-(e-caprolactone) were synthesized by electrochemical methods for the first time. The molar percent of s-caprolactone in copolymer varies from 0 to 40 % under different reaction conditions. When the content of e-caprolactone reaches 40 %, the conductivity of copolymer is 0.6 S/cm. This result implies that the copolymer may have graft or block structure. The cyclic voltammetry indicates that the copolymer has reversible electrochemical activity, which is similar to that of Py-PO copolymer.Copolymer of pyrrole-siloxane has been synthesised for the first time, using direct electrochemical methods. When the content of polysiloxane reaches 42 %\\t. the conductivity is 2.0 S/cm. Moreover, the mechanism of pyrrole copolymerization and the effect of solvent and electrode materials were d...
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