Lattice model studies of the effect of chain flexibility on the nematic‐isotropic transition. IV. Semiflexible chain solutes in solvent molecules composed of rigid cores and semiflexible tails

1978 ◽  
Vol 69 (9) ◽  
pp. 4012-4021 ◽  
Author(s):  
F. Dowell
Keyword(s):  
Lattice Model ◽  
Chain Flexibility ◽  
Model Studies ◽  
Solvent Molecules

scholarly journals Electrochemically Obtained Polysulfonates Doped Poly(3,4-ethylenedioxythiophene) Films—Effects of the Dopant’s Chain Flexibility and Molecular Weight Studied by Electrochemical, Microgravimetric and XPS Methods

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2438
Author(s):  
Vladimir Lyutov ◽  
Varvara Kabanova ◽  
Oxana Gribkova ◽  
Alexander Nekrasov ◽  
Vessela Tsakova
Keyword(s):  
Molecular Weight ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Quartz Crystal Microbalance ◽  
Point Of View ◽  
Acid Form ◽  
Salt Form ◽  
Flexible Chain ◽  
Chain Flexibility ◽  
Redox Transitions ◽  
Solvent Molecules

Electrochemically synthesized poly(3,4,-ethylenedioxythiophene) (PEDOT) films obtained in the presence of eight different polysulfonate dopants are comparatively studied by means of electrochemical quartz crystal microbalance (EQCM) and X-ray Photoelectron Spectroscopy (XPS). Differences with respect to oxidation and doping levels (OL and DL), polymerization efficiency and redox behavior are revealed based on the interplay of three factors: the type of the dopant (acid or salt form), flexibility of the polysulfonate chains and molecular weight of the polysulfonate species. For the rigid- and semi-rigid-chain dopants, use of the salt form results in higher OL and DL values and substantial involvement of solvent molecules in the course of polymerization and redox transitions whereas in the presence of their acid form compact PEDOT films with minor ionic-solvent fluxes upon redox transitions are formed. In contrast, use of the salt form of the flexible chain polysulfonates results in PEDOT with lower OL and DL in comparison to the corresponding acid form. Significant effects are observed when comparing flexible chain dopants with different molecular weights. From a practical point of view the present investigations demonstrate the large scope of possibilities to influence some basic properties of PEDOT (Ol and DL, intensity and type of the ionic and solvent fluxes upon redox transition) depending on the used polysulfonate dopants.

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