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A novel polymer network with NIR induced shape memory behaviour and plasticity.

Inspired by life assembly systems, the construction of transient assembly systems with spatiotemporal control is crucial for developing intelligent materials. A widely adopted strategy is to couple the self-assembly with chemical reaction networks. However, orchestrating the kinetics of multiple reactions and assembly/disassembly processes without crosstalk in homogeneous solutions is not an easy task. To address this challenge, we propose a generic strategy by separating components into different phases, therefore, the evolution process of the system could be easily regulated by controlling the transport of components through different phases. Interference of multiple components that are troublesome in homogeneous systems could be diminished. Meanwhile, limited experimental parameters are involved in tuning the mass transfer instead of the complex kinetic matching and harsh reaction selectivity requirements. As a proof of concept, a transient metallo-supramolecular polymer (MSP) with dynamic luminescent color was constructed in an oil-water biphasic system by controlling the diffusion of the deactivator (water molecules) from the water phase into the oil phase. The lifetime of transient MSP could be precisely regulated not only by the content of chemical fuel, but also factors that affect the efficiency of mass transfer in between phases, such as the volume of the water phase, the stirring rate, and the temperature. We believe this strategy can be further extended to multi-compartment systems with passive diffusion or active transport of components, towards life-like complex assembly systems.

Kinetic control over structures and functions of complex assembly systems has aroused widespread interest. Understanding the complex pathway and transient intermediates is helpful to decipher how multiple components evolve into complex assemblies. However, for supramolecular polymerizations, thorough and quantitative kinetic analysis is often overlooked. Challenges remain in collecting the information of structure and content of transient intermediates

Molecular face-rotating polyhedra (FRP) exhibit complex stereochemistry, rendering it challenging to manipulate their assembly in a stereoselective manner. In our previous work, stereocontrolled FRP were gained at the cost of losing the confined inner space, which hampers their host–guest interactions and potential applications. Through a rational design approach, herein we demonstrate the successful construction of hollow FRP with high diastereoselectivity. Whereas the [4 + 4] imine condensation of meta-formyl substituted C3h-symmetric TAT-m and C3-symmetric Tri-NH2 led to the formation of all feasible FRP-12 diastereoisomers; the para-substituted constitutional isomer, TAT-p, exclusively assembled into a pair of homo-directional enantiomeric FRP-13-CCCC/AAAA with a cavity size larger than 600 Å3. Detailed structural characterizations and theoretical investigations revealed the thermodynamic landscape of FRP assembly can be effectively shaped by modulating the van der Waals repulsive forces among the facial building blocks. Our work provided a novel strategy towards stereospecific assembly of pure organic cages, opening up new opportunities for further applications of these chiral materials., The rationally engineered facial units, TAT-m and TAT-p, resulted in distinct diastereoselectivity of face-rotating polyhedra (FRP).

This communication describes the fabrication of supramonomers based on supramolecular complexation between cucurbit[8]uril and the tetrapeptide Phe-Gly-Gly-Cys. The supramolecular polymers are obtained by thiol–ene click polymerization of the supramonomers with maleimide-terminated poly(ethylene glycol). Benefiting from the green and pH dependent nature of thiol–ene click reaction, it is expected that this line of research will enrich the methodology for fabricating supramolecular polymers with controlled compositions and structures.

Materials responsive to reactive oxygen species (ROS) at a physiological level are of great significance in diagnostic and therapeutic applications. We have synthesized a water-soluble tellurium-containing hyperbranched polymer and demonstrated that it forms a kind of ROS-responsive aggregate. In aqueous environment, the polymer aggregates can swell under biologically relevant concentration of H2O2, which could be expected to find applications in fields such as elimination of excess ROS.

This communication describes the fabrication of diselenide-containing supramolecular polymers. The diselenide-containing supramolecular polymers were fabricated by equimolarly mixing (FGGC11Se)2 and CB[8] in aqueous solution driven by host–guest interactions between cucurbit[8]uril (CB[8]) and Phe-Gly-Gly. The amphiphilic diselenide-containing supramolecular polymers could further form aggregates for loading hydrophobic small molecules such as Nile Red and releasing them upon addition of oxidants or reductants. This line of research not only expands the library of selenium-containing polymers, but also offers a new strategy to develop functional supramolecular polymers for drug delivery.

This communication describes a new method of fabricating supramolecular polymers through supramolecular polymerization of supramonomers. To mix building blocks of Phe-Gly-Gly linked with an azobenzene group and cucurbit[8]uril (CB[8]) in a molar ratio of 2 : 1 in aqueous solutions, supramonomers were obtained by host–guest interaction between tripeptide and CB[8]. Then supramolecular polymers were formed spontaneously by mixing the supramonomers with bis-β-cyclodextrins in a molar ratio of 1 : 1 in an aqueous solution through noncovalent host–guest complexation of the azobenzene group and β-cyclodextrin. Considering that various noncovalent interactions can be used to drive the formation of supramonomers and the supramolecular polymerization of the supramonomers, this study can enrich the methodology of fabricating supramolecular polymers.

In contrast with macromonomer in traditional polymer science, supramonomer refers to a monomer that is fabricated by noncovalent interactions, but is able to polymerize using conventional methods of polymerization. This communication describes the fabrication of a supramonomer based on supramolecular complexation between cucurbit[8]uril and the tripeptide Phe-Gly-Gly derivative. The supramolecular polymer is obtained by click polymerization of the supramonomer. It is expected that this line of research will provide a new method for fabricating supramolecular polymers.

Cucurbit[7]uril (CB[7]) as a "protective agent" can effectively inhibit the [4+4] photochemical reaction of 1,1'-(butane-1,4-diyl)bis(2-aminopyridine)bromide (DPAD) by host-guest interaction between CB[7] and DPAD. In addition, the host-guest complex DPAD-CB[7] as a supramolecular sensor can detect the concentration of 1-adamantanamine with good sensitivity and selectivity because of the guest competitive complexation.