Polymer chain mobility deformability

Decreased mobility of adsorbed chains has been observed and proved in many cases both in the melt and in the solid state [52-54] and changes in composite properties are very often explained by it [52,54]. Overall properties of the interphase, however, are not completely clear. Based on model calculations the formation of a soft interphase is claimed [51], while in most cases the increased stiffness of the composite is explained by the presence of a rigid interphase [55,56]. The contradiction obviously stems from two opposing effects. Imperfection of the crystallites and decreased crystallinity of the interphase should lead to lower modulus and strength and larger deformability. Adhesion and hindered mobility of adsorbed polymer chains, on the other hand, decrease deformability and increase the strength of the interlayer. 

The end result is the same with both oxidative and reductive doping, however, because it is not the sodium or iodide ion formed that is mobile, but the deformation of the polymer chain itself that results in a flow of current through the molecule. 

Rubber materials are soft, elastic solids, made of mobile, flexible polymer chains (with a glass transition temperature (Tg) typically lower than 0 °C) which are linked together to form a three-dimensional network. They are characterised by a low, frequency independent elastic modulus (of the order 105 to 106 Pa) and usually by a large maximum reversible deformation (up to a few hundred per cent). Rubber elasticity is based on the properties of crosslinked polymer chains at large spatial scales, the presence of crosslinks ensures the reversibility of the deformation, while at short scales, mobile polymer chains behave as molecular, entropic springs. 

The disadvantage, however, of stiffer polymer chains is reduced mobility. This has as a consequence a higher resistance to deformation processes in the bulk and therefore processing should be carried out at a temperature higher... 

These ionic crosslinks decrease chain mobility, less energy is dissipated and less plastic deformation takes place. Also, as we will describe, the ionomers with low ion content show poorer fatigue performance with increasing ion content. Evidently, the loss of chain mobility causes embrittlement of glassy polymers, and this is probably responsible for the observed effects seen here in ionomer samples with low ion content. 

The theory of relaxation spectra in polarized luminescence for various dynamic models of a flexible polymer chain has been developed by several groups of workers. Wahl has proposed a theory for the model of Gaussian subchains. The authors and coworkers used dynamic chain models consisting of rigid or deformable elements with continuous visco-elastic mechanism of mobility and rotational-isomeric lattice chain... 

High static and dynamic flexibility of the polysiloxane chain, associated with a very low energy barrier to rotation around their skeletal bonds and a low energy of deformation of the SiOSi bond angle, make the polymer soluble in many solvents. The catalyst attached to such a mobile polymer chain, which can adopt many conformations, is available for the interaction with reactants in a... 

An extra electron put on a polymer chain deforms the chain and forms a SWAP (Solitary Wave Acoustic Polaron). The SWAP dynamics and energy dissipation are such that the smallest field causes it to move at approximately the sound velocity its mobility is ultra high, higher than that of any conventional semiconductor. Increasing field changes the shape of the SWAP, but does not increase the speed. 

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