Physical chemistry of supramolecular polymer networks

Abstract

Supramolecular polymer networks are three-dimensional structures of crosslinked macromolecules connected by transient, non-covalent bonds; they are a fascinating class of soft materials, exhibiting properties such as stimuli-responsiveness, self-healing, and shape-memory. This critical review summarizes the current state of the art in the physical-chemical characterization of supramolecular networks and relates this knowledge to that about classical, covalently jointed and crosslinked networks. We present a separate focus on the formation, the structure, the dynamics, and the mechanics of both permanent chemical and transient supramolecular networks. Particular emphasis is placed on features such as the formation and the effect of network inhomogeneities, the manifestation of the crosslink relaxation dynamics in the macroscopic sample behavior, and the applicability of concepts developed for classical polymer melts, solutions, and networks such as the reptation model and the principle of time-temperature superposition (263 references).

A toolbox of oligopeptide-modified polymers for tailored elastomers

“…To this end, we investigate a series of novel supramolecular materials from mixtures of oligopeptide-modified and unmodified poly(isobutylene)s (PIBs). Extending on previous examples of supramolecular networks [32][33][34][35][36][37][38][39] , these materials show an additional formation of defined nanostructures. The length-dependent aggregation of the oligopeptides results in the formation of either small hydrogenbonded aggregates that serve as physical cross-links in the material, or mixtures of single b-sheet tapes and stacked b-sheet nanofibrils that provide a secondary network and serve as a reinforcement (Fig.…”

“…However, the thermomechanical properties of the corresponding bulk materials have rarely been studied in much detail [29][30][31] . Supramolecular materials from polymers with other types of hydrogen-bonded end groups have frequently been used to obtain thermoplastic elastomers with superior processing behaviour at elevated temperatures [32][33][34][35][36][37][38][39] . In these materials, network formation by non-covalent interactions allows for dynamic reorganization processes, which is relevant for selfhealing or thermoresponsive materials 40,41 .…”

Properties and Customization of Sensor Materials for Biomedical Applications

“…The combination of ILs with block polymers is particularly appealing as it should allow better control at the nanoscale, which may improve control over phase transitions, and mechanical and chemical properties (332). In addition, research into supramolecular polymers networks may help in obtaining intelligent sensors by means of noncovalent interactions via a bottom-up approach (333,334). For example, rubbery-metallo supramolecular polymers have shown self-healing by exposure to UV light, which may be an interesting feature for biosensing materials capable of self-regeneration or repair (333).…”

“…In addition, research into supramolecular polymers networks may help in obtaining intelligent sensors by means of noncovalent interactions via a bottom-up approach (333,334). For example, rubbery-metallo supramolecular polymers have shown self-healing by exposure to UV light, which may be an interesting feature for biosensing materials capable of self-regeneration or repair (333). Research is ongoing into skin-like gel behavior, wherein the signal is amplified throughout the system in response to an environmental stress or chemical input.…”

Dendronized Polymers with Ureidopyrimidinone Groups: An Efficient Strategy To Tailor Intermolecular Interactions, Rheology, and Fracture

“…[1][2][3] The versatility of their properties, which can vary from solid-like (for example, gels) to liquid-like, gives them a central role in several technological advances, including self-healing 4 and reinforced materials [5][6][7] , sensors 8,9 , cosmetics 10 , and drug delivery. 11,12 Despite the large body of literature on the dynamics of transient networks from associating polymers, tailoring the molecular features of polymers in order to achieve optimal properties, e.g.…”