We report on the thermoelectric properties of the polyaniline hydrochloride as a function of the temperature. In order to stress the influences of both the synthesis and the samples preparation on the thermoelectric efficiency, we have systematically measured the electrical conductivity, the thermopower, and the thermal conductivity. We show that several parameters such as the polymerization temperature and the pressure used to compress powders are crucial in order to optimize the thermoelectric performance. The microscopic origins of the transport coefficients are also discussed. In particular, the overall dataset of the measured electrical conductivity is found to scale onto a master curve involving a unique microscopic length, which coincides with the total bond length of the repeating unit of the polymeric chain. We believe that the drawn conclusions can hold for most of the conducting polymers and are thus potentially generic.

We report on both the electrical and thermoelectric transport properties as a function of temperature in polyaniline doped with camphor sulfonic acid (CSA) for a wide range of CSA doping. A transport crossovers diagram illustrating metallic and insulating like behaviors is proposed and seems to result from the interplay between charge doping and disorder. In particular, the one half doping not only leads to an optimal electrical conductivity reaching 120 S/cm at 300 K but also the lowest thermopower slope. The measured thermopower appears closely related to the metallic onset in agreement with a metallic origin of its linear temperature dependence.

In order to improve the permanence of the plasticizer in a poly(vinylch1oride) (PVC) compound we have studied the free radical polymerization and grafting of decyl methacrylate (DMA) onto PVC in the presence of a lead stabilizer. The influence of different parameters has been investigated and homogeneous PVC-g-PDMA copolymers have been obtained. Their molecular weights and the glass transition temperatures were consistent with the grafted nature of the copolymers. ZUSAMMENFASSUNGUm die Weichmacherpermanenz in PVC zu verbessern, wurde Decylmethacrylat (DMA) in Gegenwart eines Bleistabilisators (LS) mittels radikalischer Polymerisation auf PVC gepfropft. Die Molekulargewichte und Glastemperaturen der erhaltenen Produkte bestltigten, d& homogene PVC-g-PDMA-Copolymere entstanden waren.

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