Interactions inter-chain

These types of polar monomer provide sites for hydrogen bonding which increase the cohesive strength of the PSA because of strong inter-chain interaction, and they can also allow for hydrogen bonding or other polar interactions with some substrates. 

Now we assume that the inter and the intrapart are additive in a way that the inter chain interaction is given by the pairwise overlap of the ellipsoids of the different chain. Since each mass tensor corresponds to a density distribution we can describe the interchain free energy contribution of the pair ij ... 

This refinement of the constrained-junction model is based on re-examination of the constraint problem and evaluation of some neutron-scattering estimates of actual junction fluctuations [158, 159]. It was concluded that the suppression of the fluctuations was over-estimated in the theory, presumably because the entire effect of the inter-chain interactions was arbitrarily placed on the junctions. The theory was therefore revised to make it more realistic by placing the effects of the constraints along the network-chain contours, specifically at their mass centers [4, 160, 161]. This is illustrated in the second portion of Figure 2. Relocating the constraints in this more realistic way provided improved agreement between theory and experiment. 

Most of the studies on polymers such as polyamides in solution are limited because the insolubility of these polymers in common solvents. This fact makes their characterization very difficult [87] The degree of order or crystallinity shown by these polymers caused by intra- and inter- chain interactions affect their solubility and their general properties. 

Finally, it should be stressed that photoluminescence has usually a larger quantum yield in solution than in the solid state27. In the latter case, inter-chain interactions appear to quench the luminescence properties through a mechanism that is not fully understood yet. In this context, it is, however, useful to note that the possibility that the polaron-excitons evolve into excimers28 is ruled out by the absence of Stokes shifts in good-quality PPV oligomer and polymer samples14. 

Static H 2D NOE spectroscopy was applied in a first experiment showing that the technique can be used to measure inter-chain interactions [44], This work was then continued by applying the technique under MAS to investigate the inter-molecular interactions responsible for the miscibility in polybutadiene/polyisoprene blends above the Tg [45]. It was shown that intermolecular association can be probed by this technique and the results reveal the existence of weak intermolecular interactions between the polyisoprene methyl group and the vinyl side chain of the polybutadiene. 

Zimm s approximation [5] assumes that inter-chain interactions occur only through single contacts. Given two monomers i and j that belong to two different chains (say, called 1 and 2), the two-chain distribution function is ... 

The M-I transition in doped CPs is mainly governed by the extent of disorder, inter-chain interaction and doping level.88 89 It is well known that disorder potentials can localize the electronic states. If the random component of the disorder potential is large with respect to the bandwidth, then the localization of electronic wave functions can occur. In the presence of strong disorder, the overlap of the wave functions drops off exponentially and the system moves towards the insulating regime. 

A straightforward consequence of such strong interactions (in the absence of inter-chain interactions, such as in very dilute solutions) would be aggregation (or clustering) of these segments, a situation that can be termed self-association. Such a... 

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