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Dynamic structure factors flexible polymers

This EVB model was employed to the systematic study of model pores or channels. Taking a simphstic view, the polymer was regarded as a rigid framework in which slab or cylinder pores of constant thickness or radius, respectively, are formed. Within this approach, proton transport in pores has been studied as a function of a variety of generic structural and dynamical features of the polymer and operational parameters of the working fuel cell (such as temperature and humidity). These studies revealed a number of factors determining the proton mobihty, such as the width of the channel, distance between the sidechains, and their flexibility. The main lessons of the simulations and the theoretical analysis were ... [Pg.38]

For the tyrosine-derived polycarbonates tested, the enthalpy relaxation process was not sensitive to the length of the pendent chain. This obser ation suggests that structural relaxation in these polymers is limited by backbone flexibility, and that the fraction of free volume in these polymers is not the limiting factor for polymer mobility. Furthermore, since the enthalpy relaxation time is short at aging temperatures of Tg-15°C, a few hours of storage at that temperature will be sufficient to bring the physical aging process to completion. The results obtained by dynamic... [Pg.268]

Let us consider the stracture factor for a binary polymer blend of flexible chains based on the RPA discussed in Section 2.10.2.1.3 and drflusive dynamics in Section 2.10.2.2.3. All essential information has already been given, except for the unperturbed structure factors. These are given by eqn [25]... [Pg.324]

The resolution of the available methods depends on several factors, such as the type of nuclei studied, chain dynamics, sample concentration, solvent, and temperature. Another important variable, linewidth, is related to the spin-spin relaxation time and hence, to the correlation time. Thus, large rigid molecules are expected to have broad lines. However, the flexibility of the polymer chains in solution allows high-resolution structures to be observed. Especially for the side chains, less constrained than the main ones, sharper resonances are obtained. [Pg.215]


See other pages where Dynamic structure factors flexible polymers is mentioned: [Pg.24]    [Pg.207]    [Pg.17]    [Pg.11]    [Pg.201]    [Pg.1652]    [Pg.322]   


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Dynamic structure factor

Dynamical structure factor

Flexibility, structural

Flexible polymer

Flexible structures

Polymers factors

Structural dynamics

Structural factors

Structure dynamics

Structure factor

Structure flexibility

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