Macromolecules

Abstract Polyurethane (PU) is the sixth largest class of polymers by utilization, and thermoset PUs (including foams and elastomers) account for over 97% of all PUs. Unfortunately, traditional thermoset PUs are non-recyclable due to their cross-linked structure, leading to over 90% of these plastics being incinerated or deposited in landfills. To tackle end-of-life challenges of thermoset PUs, re…

Abstract Chemical recycling of polyesters to re-form the constituent monomers is essential for a circular plastic economy. The ring-opening copolymerization (ROCOP) of epoxides and cyclic anhydrides represents an important route to polyesters and has received considerable attention over the past decades. In contrast, the chemical recycling of such polyesters has been only sporadically investigate…

Abstract Polyurethane elastomers are favored for damping applications owing to their tunable structure and effective vibration attenuation. However, conventional systems, which rely primarily on segmental mobility within the glass transition region, often struggle to achieve high damping performance over a broad frequency range. To overcome this limitation, we developed a novel polyurethane elast…

Abstract Blending block copolymers (BCPs) with polymeric additives provides a direct route to controlling microphase separation, yet how such additives alter composition fluctuations remains incompletely understood. Here, we examine the order–disorder transition (ODT) in symmetric AB diblock copolymers mixed with either neutral random copolymers (RCPs) or symmetric pairs of A and B homopolymers (…

Abstract Polylactic acid (PLA) components fabricated by fused filament fabrication (FFF) typically suffer from poor interlayer bond strength. Owing to PLA's intrinsically weak crystallization ability, the role of crystallization in interlayer bonding has rarely been investigated, limiting the development of interfacial enhancement strategies. To address this, we designed a PLA printing material w…

Abstract The nozzle geometries associated with extrusion-based 3D printing impart significant spatial heterogeneities in both the type (shear vs extension) and rate of the flows applied during extrusion. For polymeric and nanostructured inks, these heterogeneous flow histories influence the underlying structure at the nano- to microscale. We previously demonstrated that HOT-DIW 3D printing can or…

Abstract Identifying the structural precursors that govern plastic deformation in amorphous polymers remains a longstanding challenge due to the absence of well-defined defect structures common in crystalline solids. In this study, we investigate the molecular origins of stage transitions in amorphous polycarbonate by integrating coarse-grained molecular dynamics with persistent homology, a topol…

Abstract Easy construction of rhodamine spiro rings and diversity of naphthalenediol enable various isomers of the naphthalene-fused double rhodamine structure and provide the possibility to study the structure–performance relationship of double-spiro mechanophores. Herein, we for the first time report the isomer effect of double-spiro mechanophores in polymer mechanochemistry. Three double rhoda…

Abstract Boric acid groups, containing CO2-philic hydroxyl functionalities that exhibit strong affinity toward CO2 molecules, play a pivotal role in enhancing the selective CO2 adsorption and separation performance of microporous organic polymers. However, their electron-withdrawing character and existing synthetic limitations have hindered the straightforward incorporation of boric acid moieties…

Abstract We extend the microscopic self-consistent cooperative hopping theory (SCCHT) of activated ion dynamics in polymerized ionic liquids (PolyILs) and glasses based on a trained polymer physics model to provide an understanding of the effect of cation size on the physical barrier and ion relaxation time as a function of temperature. Speeding up of ion hopping with increasing cation size due t…

Abstract Polyamide-6 (PA6) fibers are widely used owing to their excellent mechanical properties, outstanding processability, and superior resistance to abrasion and wear. However, PA6 fibers with high tensile strength remains in urgent demand to meet the requirements of emerging application environments. Herein, we present a strategy of reinforcing PA6 fibers by incorporating a small amount (0.5…

Abstract The fabrication of high-strength and super-tough polylactide (PLA) products without the addition of any foreign toughening agents remains a significant challenge, particularly in building up the quantitative relationship between crystalline microfibrillar superstructures and impact toughness. In this work, an exceptional combination of both high notched Izod impact strength and tensile s…

Abstract Earth-abundant nickel-catalyzed carbonylative polymerization of olefins offers a cost-effective alternative to conventional precious palladium catalysis, but the homogeneous nature of this catalyst causes severe reactor fouling that precludes industrial application. Herein, we report the first heterogeneous nickel-catalyzed carbonylative polymerization based on immobilization of a phosph…

Abstract Depolymerization, the complete degradation of a polymer into its monomers, is of great interest for the development of circular materials. But current depolymerizations require high temperatures, suffer from low monomer recovery, and/or require a separate repolymerization step. Herein, unsubstituted 1,2-dithiolane, which is unstable in pure form, was successfully prepared, stored, and po…

Abstract Thermally latent curing agents are essential for one-component epoxy systems, enabling long pot life while maintaining high reactivity upon activation. However, strategies for imparting thermal latency to highly reactive tertiary amines remain limited. Herein, we propose a simple and novel approach based on betaine formation between tertiary amines and acrylic acid. This strategy effecti…

Abstract To develop highly thermally stable thermoset materials and achieve a deep understanding of the chemical structure–physical property relationship of polybenzoxazines, a series of chalcogen-containing bis-benzoxazine monomers (PH-O, PH-S, PH-Se, and PH-Te) were designed and synthesized in the current work. The chemical structures of chalcogen-containing bis-benzoxazines were characterized …

Abstract Compared to natural rubber (NR), petroleum-derived synthetic rubbers (SR) generally exhibit greater structural diversity and thermal stability. However, due to the lack of nonrubber components such as phospholipids and proteins, the mechanical properties of SR, such as strength and toughness, are far inferior to those of NR. It is reasonable to assume that the mechanical properties of ru…

Abstract In thermal iron-catalyzed atom transfer radical polymerization, arylphosphines primarily serve as sacrificial reducing agents consumed during activator generation, thereby requiring excess phosphine (≥1.5 equiv) and high catalyst loadings (≥5000 ppm) at elevated temperatures. Here, we report that green-light irradiation (λ ≈ 525 nm) transforms phosphines from consumable reagents into reg…

Abstract This work systematically investigates the bulk self-assembly behavior of binary and ternary blends of discrete giant polymer chains, focusing on the impact of chain-length asymmetry (γ), number fraction of long chains (nA), and regio-configuration. In binary blends with large chain-length disparity at low nA (0.1–0.17), a nanoscale phase coexistence with fixed domain spacings emerges, ma…

Abstract Herein we describe a synthetic route to poly(α-aminoketones) based on the Pd-catalyzed C(sp3)–C(sp3) bond cleavage of N-protected 3-azetidinol monomers containing a haloaryl group. The reactivity of the azetidinols was sensitive to the nature of the N-protecting group. Thus, substrates with N-tert-butyloxycarbonyl or N-phenyl polymerized in the presence of catalytic amounts of Pd(OAc)2 a…