Junction zones formation models

Figure 4.12 Schematic representation of the egg-box model depicting alginate junction zone formation.

Substantial research efforts have been made to relate molecular properties to the structures of the junction zones and provide mechanisms for gel formation. Thus we have models for the formation and alignment of double helices for kappa-carrageenan, formation of triple helices for gelatin and egg box models for calcium induced gelation of alginate and pectin to mention a few examples (Morris 1986 Djabourov... 

Fig. 184. Young s modulus as a function of relative conversion a/a (finrni optical rotation) for aqueous gelatin solutions (in tripio) i eing temperature 26.9 °C. Solid lines theoretical predictions based on the cascade theory of network formation for various crosslink functionalities and maximum number of potoitial junction zones curve C, which gives the best fit, f = 6 and maximum number potential juiK tion zones = 8 [17,489j. Broken lines (a, b, c) results of calculaticms with the network model [39-44] for crosslink functionalities f = 4,6 and 8, plotted vs y/f i...

Fig. 202. Model for agarose network formation crosslinks involve both double helix formation and substantial association of double helices to form microcrystalline junction zones. Refnoduced from AdvPolym Sci [Ref. 1] by the courtesy the authors and of SteinkopffPublishers Darmstadt, FRG...

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