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Monodispersed hairy nanocomposites with typical 2 nm (isophthalic acid)24Cu24 metal–organic polyhedra (MOP) as a core protected by 24 polymer chains with controlled narrow molecular weight distribution has been probed by imaging and scattering studies for the heterogeneity of polymers in the nanocomposites and the confinement effect the MOPs imposing on anchored polymers. Typical confined‐extending surrounded by one entanglement area is proposed to describe the physical states of the polymer chains. This model dictates the counterintuitive thermal and rheological properties and prohibited solvent exchange properties of the nanocomposites, whilst those polymer chain states are tunable and deterministic based on their component inputs. From the relationship between the structure and behavior of the MOP nanocomposites, a MOP‐composited thermoplastic elastomer was obtained, providing practical solutions to improve mechanical/rheological performances and processabilities of inorganic MOPs. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomers (TPEs) have found use in a wide range of applications, such as adhesives, elastomers, coatings, fibers, and in additive manufacturing techniques such as 3D printing. Despite their omnipresence, the need for advanced TPEs with adaptive properties is continuously growing. Along with a brief historical introduction, this review presents an overview of typical structure-property relationships for various TPEs and discusses the design principles of TPEs from a synthetic chemistry perspective. Recent advances in TPEs with different macromolecular architectures, including linear ABA triblock copolymers, ABC triblock terpolymers, multiblock copolymers, star copolymers, graft copolymers, bottlebrush polymers, and hyperbranched polymers are reviewed. Service temperatures and mechanical properties of the different materials are compared in each section. Incorporating various supramolecular interactions into different macromolecular architectures as a means to further extend the range of TPE applications is also discussed. Future opportunities for TPE research in both academia and industry are addressed as perspectives. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomers (TPEs) have been widely studied because of their recyclability, good processibility, low production cost, and unique performance. The building of graft-type architectures can greatly improve mechanical properties of TPEs. This review focuses on the advances in different approaches to synthesize multigraft copolymer TPEs. Anionic polymerization techniques allow for the synthesis of well-defined macromolecular structures and compositions, with great control over the molecular weight, polydispersity, branch spacing, number of branch points, and branch point functionality. Progress in emulsion polymerization offers potential approaches to commercialize these types of materials with low production cost via simple operations. Moreover, the use of multigraft architectures provides a solution to the limited elongational properties of all-acrylic TPEs, which can greatly expand their potential application range. The combination of different polymerization techniques, the introduction of new chemical compositions, and the incorporation of sustainable sources are expected to be further investigated in this area in coming years. [ABSTRACT FROM AUTHOR]

Polybenzofulvene (PBF) is a polydiene with a very high glass transition temperature (T g), which makes it a potential candidate for use as the hard block for high-temperature thermoplastic elastomer applications. The T g s of polydienes are known to be related to chain flexibility. However, no studies have been reported that correlate the chain flexibility to the microstructure of PBF. Herein, we present a study of solution properties of linear PBFs with narrow molacular weight dispersity and having 1,2-addition ranging from 23% to 99%. The materials were prepared by living anionic polymerization under different conditions. Specifically, the chain flexibility as defined by the Flory's characteristic ratio, C ∞ , and dependence of chain flexibility on microstructure by combined measurements of intrinsic viscosity and molecular weight using triple-detector size exclusion chromatography (SEC) is studied. The persistence lengths (l p) and chain diameters (d B) were also estimated using the touched-bead wormlike chain model. To the best of our knowledge, the characteristic ratio of PBF is found to be the highest of all polydienes that have been reported so far. Image 1 • The effect of microstructure on chain flexibility and glass transition temperature of polybenzofulvene (PBF) was studied. • The solution properties of PBF were investigated by using SEC with triple-detector. • Characteristic ratio, glass transition temperature, and persistence length of the PBF increase with 1,2-microstructures. • The characteristic ratio of PBF is found to be the highest of all polydienes that have been reported so far. [ABSTRACT FROM AUTHOR]