Interactions intra-chain

The first term in right-hand side is the intrinsic intra-chain force constant given by equation (5), while the two terms within the brackets describe the contributions from interchain interactions between octahedra shifted by c/2 and a (parallel to Y in Fig. 3) along the corresponding crystal axes [25]. 

The problem of the second virial coeffident of flexible chain polymers has three phases. In the first place, there is the problem of interchain interactions in the second, the problem of the inteochain interactions and finally, the problem of the coupling of the inter- and intra-chain interactions. Different approximations are possible for each phase of the problem, various combinations of such approximations are also possible, and consequently we are confronted by a wide variety of possible theories. For example, the present development of a new excluded-volume equation for the intrachain problem almost doubles the variety of Az-theories, since most existing theories have been developed on the basis of the Flory expression for the excluded volume effect and the new theory can be combined, in prindple, with all of these theories. On the other hand, we have as yet no computational data for A2 and furthermore, the experimental accuracy of A2 measurements is still rather poor, as illustrated in Fig. 2. It is therefore unlikely that one particular combination of several approximations can be properly chosen from among the... 

If the coupling between inter- and intra-chain interactions were rigorously taken into account, the expression for h (z) would not be so simple. Different expansion factors would be needed for each term in Eq. (103). 

As a result of the same intra-chain rr-bonding and the relatively strong inter-chain electron transfer interaction, the mechanical properties (Young s modulus and tensile strength) of conjugated polymer are potentially superior to those of saturated polymers. Thus, metallic polymers offer the promise of truly high performance high conductivity plus superior mechanical properties. 

The behaviour of pectic substances in solutions involves both short and long range interactions among all the constituents of the macromolecule as well as interactions with the solvent molecules and the ions in the solutions. The calculations reported here explain the aggregation of PGA chains in acidic media as due to the formation of a network of inter-intra chain hydrogen bonds. Also the gel formation of Na- and Ca-Pectate is well reproduced. 

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