Supramolecular Polymers and Assemblies. Andreas Winter

= −100, −133, and −166 J mol⁻¹ K⁻¹, respectively) are shown; in all cases, the initial volume fraction of the monomers has been set to 0.1. Source: Modified from Dudowicz et al. [50]; Douglas et al. [51].Figure 1.9 Schematic representation of the generalized mechanism of a ring‐chain‐mediated supramolecular polymerization. The intermolecular binding constants (K_inter) are related to the intermolecular association of molecules, whereas the intramolecular binding constant K_{intra(n‐mer)} is assigned to the ring closure of monomers, oligomers, and polymers. Source: Winter et al. [39]. © 2012 Elsevier B.V. Figure 1.10 (a) Schematic representation of Kuhn's concept of effective concentration (c_eff) for a heteroditopic oligomer (i.e. having two different end groups, A and B) [74]. In solution, the end group A will experience an effective concentration of B, if the latter one cannot escape from the sphere of radius l, which is identical to the length of the stretched chain. Thus, the intramolecular association between the termini becomes favored for c_eff values higher than the actual concentration of B end groups. (b) Illustration of how the equilibrium concentration of chains and macrocycles can be correlated to the total concentration (c_t) of a ditopic monomer in dilute solution; such a ring‐chain supramolecular polymerization typically features a critical concentration. Source: de Greef et al. [26]. © 2009 American Chemical Society.Figure 1.11 (a) Illustration of the fraction of polymerized monomer as a function of K_inter·c_t for three different EM₁ values and a fixed value of K_inter (10⁶ M⁻¹). (b) Illustration of the evolution of <DP>_N as a function of K_inter·c_t for various EM₁ values. Source: Flory and Suter [91].Figure 1.12 Schematic representation of the formation of a poly(pseudorotaxane) via a ring‐chain equilibrium. Source: Cantrill et al. [95]. © 2001 American Chemical Society.Figure 1.13 Schematic representation of a typical cooperative supramolecular polymerization reaction (nucleation‐elongation mechanism). K_n and K_e represent the association constants for the nucleation and the elongation phase, respectively (K_n < K_e). Source: Winter et al. [39]. © 2012 Elsevier B.V.Figure 1.14 Schematic illustration of the energy diagrams of a cooperative nucleated (a) and a cooperative downhill supramolecular polymerization (b). In both plots, the axis of abscissae represents the oligomer's size (i), whereas the ordinate measures the ΔG⁰ in arbitrary units. In diagram (a), the size of the nucleus is 2 (i.e. dimeric nucleus); in diagram (b), a tetrameric nucleus is depicted. Source: de Greef et al. [26]. © 2009 American Chemical Society.Figure 1.15 Illustration of the various thermodynamic states in supramolecular polymerizations on Gibbs free energy landscape. Source: Sorrenti et al. [40]. Licenced under CC BY 3.0.

      2 Chapter 2Figure 2.1 Schematic representation of the basic guanidinium–carboxylate interaction as well as of several guanidinium receptor. Source: Dietrich et al. [11]; Linton and Hamilton [12].Figure 2.2 Schematic representation of the binding of N‐acetyl‐protected α‐amino carboxylates to the receptor 6. Source: Schmuck [14].Figure 2.3 (a) Schematic representation of the dimerization of the self‐complementary guanidinium derivative 7[16]. (b) Schematic representation of the supramolecular self‐assembly of the heteroditopic derivatives 8. Source: Schmuck et al. [17]. Figure reproduced with kind permission. © 1999 Wiley‐VCH and 2000 American Chemical Society, respectively.Figure 2.4 (a) Schematic representation of the self‐assembly of two complementary components in a Vernier‐type fashion (the most straightforward case, i.e. combining a ditopic and a tritopic building block is depicted). (b) Schematic representation of the self‐assembly of 9 and 10 into a molecular [2×3]‐Vernier motif. Source: Kelly et al. [21].Figure 2.5 Schematic representation of the template‐driven self‐assembly of 11 and 12 into a supramolecular rectangle. Source: Terfort and von Kiedrowski [22].Figure 2.6 Schematic representation of star‐shaped assembly 13 and the corresponding X‐ray single crystal structure (R = CF₃). Source: Kraft and Fröhlich [23]. © 1998 Royal Chemical Society.Figure 2.7 Schematic representation of the regioselective intramolecular photolysis reaction in the ion‐paired derivative 14. Source: Breslow et al. [24].Figure 2.8 (a) Schematic representation of the bowl‐shaped triple‐ions 15–18; (b) schematic representation (left) and space‐filling model of the ion pair 16 × 18 (right). Source: Grawe et al. [27]. Figure reproduced with kind permission. © 2002 American Chemical Society.Figure 2.9 (a) Schematic representation of metalloporphyrin 19 and calix[4]arene 20, as building blocks for supramolecular capsule formation. (b) Illustration of the simulated structure of the capsule (CHARMn 24.0). Source: Rehm and Schmuck [7]. © 2010 Royal society of chemistry.Figure 2.10 Schematic representation of cavitand 21 and its anion‐supported self‐assembly into a (21₂X₄) capsule (X denotes as monovalent anion). Source: Oshovsky et al. [31]. © 2006 American Chemical Society.Figure 2.11 Proposed phase diagram for the supramolecular polymer formed by HOOC–PαMS–COOH (M_W = 10 kDa) and H₂N–PI–NH₂PIP (M_W = 18 kDa). The constituent blocks phase separated at the UCST. ODT denotes the regime for the order–disorder transition of the block copolymer structure. T_g and T_i define the glass transition and dissociation temperature, respectively. Microphase separation can be observed in the left‐to‐right diagonally hatched area; the mixture of telechelic polymers is macroscopically phase separated in the right‐to‐left diagonally hatched area. In the stippled regime, the copolymer is disordered phase, and finally, the clear area represents a homogeneous mixture of the two constituent polymers. The dashed lines represent the proposed continuations of the curves, which were experimentally not accessible due to ionic aggregation and/or cleavage of the supramolecular bonds. Source: Russell et al. [47]. © 1988 American Chemical Society.Figure 2.12 (a) Scheme representation of the vesicles formed by the self‐assembly of PS‐COOH and PNIPAM‐NH₂ in aq. dioxane. (b) Representative TEM image of the thusly obtained vesicles. Source: Qian and Wu [64]. Figure reproduced with kind permission. © 2008 American Chemical Society.Figure 2.13 Transmission electron microscopy (TEM) images of ionically end‐capped PS‐b‐PI: (a) Me₃N⁺‐PS‐b‐PI; (b) Me₃N⁺ ‐ PS ‐ b ‐ PI ‐ SO₃⁻. Source: Schädler et al. [67]. Figure reproduced with kind permission. © American Chemical Society.Figure 2.14 Pictures of an “intelligent” supramolecular rubber, which exhibited (a) self‐healing and (b) shape‐memory properties. Source: Wang et al. [68]. Figure reproduced with kind permission. © 2015 The Royal Chemical Society.Figure

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