A rational strategy for the realization of chain-growth supramolecular polymerization

Abstract

Over the past decade, major progress in supramolecular polymerization has had a substantial effect on the design of functional soft materials. However, despite recent advances, most studies are still based on a preconceived notion that supramolecular polymerization follows a step-growth mechanism, which precludes control over chain length, sequence, and stereochemical structure. Here we report the realization of chain-growth polymerization by designing metastable monomers with a shape-promoted intramolecular hydrogen-bonding network. The monomers are conformationally restricted from spontaneous polymerization at ambient temperatures but begin to polymerize with characteristics typical of a living mechanism upon mixing with tailored initiators. The chain growth occurs stereoselectively and therefore enables optical resolution of a racemic monomer.

Controlling supramolecular polymerization through multicomponent self‐assembly

“…21,22 Similar to covalent polymers, mechanistic investigations of supramolecular systems have highlighted the need to differentiate between the thermodynamically controlled cooperative nucleation-elongation mechanism, noncooperative isodesmic self-assembly or ringchain equilibria, 8,[23][24][25][26][27][28][29][30] and kinetically controlled self-assembly pathways. 22,[30][31][32][33][34][35][36][37][38][39][40][41][42] However, despite the large advances in elucidating mechanistic details, strategies to rationally manipulate mechanisms and self-assembly pathways in supramolecular polymerization remain scarce. While it is possible to use the toolbox of supramolecular and physical organic chemistry to tune the affinity of a monomer for itself, via molecular design or via concentration and temperature dependent selfassembly, precise engineering of molecular weight, shape, and size of the produced supramolecular polymer remains challenging.…”

“…These could be reduced by the addition of what the authors call a chain terminator, a monofunctional (N-methyl)imidazolyl Znporphyrin. In the light of recent developments in manipulating the kinetic stabilities and kinetic pathways in selfassembled supramolecular complexes [128][129][130][131][132][133][134][135][136] and supramolecular polymers, 22,[30][31][32][33][34][35][36][37][38][39][40][41][42]130,[137][138][139][140][141][142][143][144][145] it is interesting to note, that the addition of the chain stopper to the polymers did not lead to instantaneous disassembly. 127 The expected depolymerization and shortening of the polymers based on the comonomer feed ratio was only observed when the di-and monofunctional comonomers were premixed in a good FIGURE 3 (a) Chemical structures for the bi-and monofunctional phosphine ligands, P(Phe) 2 C 12 (Phe) 2 P and P(Phe) 2 C 12 , in order to prepare palladium(II)-based coordination polymers.…”

Monodisperse Cylindrical Micelles and Block Comicelles of Controlled Length in Aqueous Media

“…38, [49][50][51][52][53][54][55] These developments have also provided access to new building blocks that allow the construction of a variety of complex hierarchical superstructures. [56][57][58][59][60] Herein, in an attempt to tackle the above-mentioned limitations, we report the preparation of well-defined, water-soluble cylindrical micelles of controlled length over a broad range up to 1.10 µm, with the added advantage of having a readily functionalizable coronaforming block.…”

Supramolecular Interfacial Polymerization: A Controllable Method of Fabricating Supramolecular Polymeric Materials

“…Owing to the dynamic nature of the noncovalent interactions, supramolecular polymers exhibit unique properties such as reversibility, stimuli‐responsiveness, self‐healing, and good processability 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30. Over the past decades, significant advances have been made in developing methods of supramolecular polymerization, from spontaneous to controllable and living supramolecular polymerization 31, 32, 33, 34, 35, 36, 37, 38. Furthermore, supramolecular polymers have displayed potential applications in many interdisciplinary fields, such as molecular muscles,39, 40, 41 self‐healing materials,42, 43, 44 self‐healing organic electronics,45, 46 heterogeneous catalysis,47 degradable drug nanocarriers,48 and stimuli‐responsive supramolecular gels 49, 50, 51…”