Interchain order

NanoPQT dispersion, with n-n stacking reflection (d) XRD of annealed PQT-12 film, with reflections for interchain ordering only at 26= 5.1°, 10.1°, 15.2° (e) electron micrograph of annealed film showing n-n stack reflection and (f) schematic representation of PQT-12 lamellar n-n stacking structure [46]. 

Hydrochloric acid as well as camphor sulfonic acid doped polyaniline prepared in chloroform often have [59] log a proportional to T as expected for quasi-one-dimensional variable range hopping, Equations (3) and (4). Generally, the higher conductivity samples have a weaker temperature dependence at low temperatures (Tq 700-1000 K for T<80 K), and lower conductivity samples a stronger temperature dependence (To 4000 K). The smaller Tq for the more highly conducting samples has been associated with weaker localization due to improved intrachain and interchain order. 

Structure models based on the data obtained from diffraction studies are now starting to make their contribution to the development of quantitative and more chemically specific theoretical descriptions of conjugated polymers. A more precise knowledge of the actual chain geometry and interchain ordering ( packing ) will help these theories advance beyond the onedimensional isolated-chain approximation. 

Yet another advantage of higher-MW materials over small molecules is their smaller polaron relaxation energies [99], so that the turn-over from polaron-like to band-Uke transport should, in principle, occur at a lower degree of interchain order. This provides an additional explanation of the higher mobilities in higher-MW polymers, as compared to more crystalline, but lower-MW materials longer chains tolerate more disorder. 

True metals in which the carrier mean free path is at least a few lattice constants This only becomes relevant for those polymers in which the electrical conductivities are in excess of several hundred S/cm. In such systems, the molecular weight is sufficiently high, interchain order is sufficiently good, and... 

The theoretical simulations we have reviewed here are consistent with the changes in optical absorption observed experimentally when the degree of interchain order is improved in alkyl-substituted polythiophene derivatives [60,61]. The CMS spectrum of RR-P3HT exhibits a pronounced charge-induced... 

Improving the overall extent of structural order to a level approximating that seen in crystalline PA or PPV films has had very limited success [111,112]. Notwithstanding this result, PANi may still be processed and oriented, even in a fully amorphous state [84], and then doped to conductivities in excess of 100 cm Even higher levels are seen in partially crystalline films [83]. Achieving substantially larger values probably will require improved interchain ordering, but there are many applications that are perfectly acceptable at this lower level. 

Silva, C., et al. 2002. Exciton and polaron dynamics in a step-ladder polymeric semiconductor The influence of interchain order. J Phys Cond Mat 14 9803. 

Yoda O, Kuriyama 1, Odajima A. Interchain ordering in amorphous sohd polyethylene. Appl Phys Lett 1978 32 18-20. 

Chain Stretching, Salt Effects and Interchain Ordering... 

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