Multistage open association

Figure 2. Theoretical relationship between the association constant Ka and DP, using a simple isodesmic association function, or multistage open association model.

Fig. 2 Growth mechanisms. Schematic theoretical variation of DP (or length) with unimer concentration for linear supramolecular polymerization according to (a) multistage open association (b) helical growth (c) growth-coupled-to-orientation. C and C are eritieal eoneentrations coiresponding to (b) and (c). Occurrenee of liquid-eiystalline phases (N. H, L) is indicated. From Ref. [1]. Copyright 2002 Wiley-VCH.

The scheme of supramolecular association of n monomeric units (unimers) M into a linear sequence (multistage open association (MSOA)) is [35-41]... 

Figures (a) Plots of DPn and DPw as functions of KCq for isodesmic polymerization without byproduct. (From D. Zhao and J.S, Moore. Org. Biomol. Chem. 2003. Copyright 2003 RCS.) (b) Theoretical relationship between the association constant Kan6 DP according to the multistage open association model. (From L. Brunsveld, B.J.B. Folmer, E.W. Meijer, and R.R Sijbesma. Chem. Rev. 101 4071, 2001. Copyright 2001 ACS.)...

Equilibrium polymers (EPs). Apparently the most common type of supramolecular polymer, in which all the monomers present in the system are active, that is, are able to bond with each other and form polymeric assemblies. Examples are given in Figure 2. In single-component EPs aU bonded interactions are plausibly equivalent, a case sometimes also referred to as the isodesmic equilibrium polymerization, or, in Chapter 2, as the multistage open association (MSOA). 

The scheme of multistage open association (MSOA) of s monomeric units ( un-imers ) Mj into a linear sequence Mj is [6,97-100]... 

Sugihara, S., Kanaoka, S. and Aoshima, S. (2004) Stimuli-responsive ABC triblock copolymers by sequential living cationic copolymerization multistage self-assemblies through micelliza-tion to open association. /. Polym. Sci. Part A, Polym. Chem., 42,2601-2611. 

Let us discuss open multistage association in diluted polymer solutions. It might be modeled as follows ... 

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