Recent advances in understanding kinetically controlled pathway complexity have greatly promoted the precision control of supramolecular polymerization. Among them, seeded living supramolecular polymerization (LSP) has proven highly effective for constructing supramolecular polymers with tailored lengths, dispersities, and sequence-defined structures. However, conventional noncovalent interactions often suffer from intrinsic environmental sensitivity, which compromises the kinetic stabilization of metastable species by prematurely activating dormant conformations, thereby undermining the fidelity and stability of the LSP process. Herein, we report a cation–π interaction–dominated strategy for active control of supramolecular polymerization, in which distinct binding modes are dynamically switched and modulated by reversible photoisomerization of azobenzene. This design enables efficient capture and stabilization of metastable states, offering integrated control over both polymerization kinetics and structural outcome. A model monomer, Trans-M1, was designed with a trans-azobenzene core bearing aromatic cationic and π-units at its termini. Trans-M1 undergoes spontaneous 2D supramolecular polymerization via alternating intermolecular cation–π interactions to form ordered nanosheets (Pathway A). Upon 365 nm light irradiation, the monomer folds into a dormant conformation stabilized by intramolecular cation–π interactions (Pathway B). Subsequent 460 nm irradiation triggers unfolding of the dormant species into active monomers, which bypass the nucleation barrier and initiate rapid LSP when exposed to 2D nanosheet seeds (Pathway C). Additionally, rapid quenching of the Trans-M1 monomer leads to the formation of deeply kinetically trapped one-dimensional (1D) nanofiber aggregates with considerable stability, which do not spontaneously convert into the thermodynamic product over time (Pathway D). This work demonstrates that integrating photoresponsive conformational switching with tunable cation–π binding enables full-pathway regulation of supramolecular polymerization across multiple energy landscapes. The approach establishes a generalizable framework for metastable species control and dynamic structural modulation in functional supramolecular materials.

Efficient hydrolysis of lignocellulosic biomass to monosaccharides is a challenging step and the primary obstacle for the large scale production of cellulosic biofuels and chemical feedstock for polymer applications [1]. Ionic liquids are well known for their ability to dissolve cellulose. 

Our interest in the search for efficient catalytic methods for saccharification of polysaccharides has led us to develop -SO₃H group functionalized Brönsted acidic ionic liquids (BAILs) as solvents as well as catalysts [2], [3]. Later we found that these sulfuric acid derivatives can be used as catalysts in aqueous phase as well. For example, BAIL 1-(1-propylsulfonic)-3-methylimidazolium chloride aqueous solution was shown to be a better catalyst than H₂SO₄ of the same [H⁺] for the degradation of cellulose [4]. This observation is an important lead for the development of a BAIL based cellulase mimic type catalyst for the depolymerization of cellulose. Furthermore, we have investigated the effects of selected metal ions on 1-(1-propylsulfonic)-3-methylimidazolium chloride BAIL catalyzed hydrolysis of cellulose in water at 140-170 °C. These results show that cellulose samples heated with Mn²⁺, Fe³⁺, Co²⁺ as co-catalysts produce significantly higher TRS yields compared to the sample heated without the metal ions. 

This talk will present the development of BAIL based artificial cellulase type catalysts in aqueous, alcohol and acetone mediums, QSAR studies, catalyst immobilizations, applications on lignocellulosic biomass materials such as corn stover, switchgrass and poplar as well as catalyst recycling studies.

The global plastic waste crisis persists as a pressing environmental challenge, with conventional degradation methods revealing fundamental technical constraints. Current industrial-scale recycling approaches suffer from downcycling effect, restricted applicability, and concomitant microplastic generation, [1,2] which underscores the urgent demand for transformative recycling paradigms that harmonize operational simplicity, economic feasibility, and minimal resource expenditure.

Sunlight-drive decomposition represents a revolutionary paradigm, which operates under ambient conditions with near-zero energy input, positioning a scalable and environmentally benign management solution. [3] However, achieving complete decomposition while maintaining essential material performance constitutes a critical technological hurdle.

we present a transformative materials design strategy as a potential solution to the problem. This design philosophy stems from our previous discovery that a polydiacetylene containing short carboxylic acid side groups undergoes complete degradation into small molecules under sunlight in either air or aqueous environments, primarily through the cleavage of its C=C and C≡C bonds in the backbone. [4] Intriguingly, the topochemical polymerization mechanism inherent to polydiacetylenes is particularly advantageous for crystalline engineering plastics with regularly aligned polymer strands. Using industrial crystalline engineering plastic polyamide 6/10 (nylon 6/10, or PA610) as a model system, our design introduces diacetylene moieties within the strands of PA610 while maintaining the commercial-grade properties of the materials in terms of mechanical properties and transparency. When exposed to sunlight, the inter-chain topochemical polymerization among adjacent diacetylene units occurs, creating a crosslinked network embedding photodegradable elements in both crosslinkers and polymer strands. The derived material then completely degrades in natural environment within 5 months. 

This sunlight-responsive switching mechanism elegantly reconciles the conflicting requirements of structural robustness during service life and controlled degradability at end-of-life, establishing a new paradigm for sustainable materials engineering.

Biomacromolecules such as DNA, proteins, and polysaccharides possess unique helical structures, which are closely related to various biological activities involving recognition, catalysis, replication, genetic information storage, etc.^[1-3] To date, many artificial foldamers have been designed because they can act as the ideal systems to simulate the structures and functions of biomacromolecules.^[4] Herein, we have synthesized a water-soluble poly(m-phenylene ethynylene)-based foldamer bearing L-alanine sodium pendants, whose solvent-driven helix inversion can be visualized with the aid of a tetraphenylethene-functionalized hemicyanine dye based on the restriction of intramolecular motions (RIM) and intramolecular charge transfer (ICT) mechanisms. In addition, another foldamer bearing L-alanine hexyl ester pendants is synthesized, showing a weak circularly polarized luminescence (CPL) signal in solution, but has a significant blue-colored negative CPL signal with a dissymmetry factor (g_lum) of -0.01 in film.  A benzothiadiazole dye-based achiral fluorescent film is prepared. Then, the two films are arranged side by side. When the foldamer film is close to the excitation light, a yellow-colored negative CPL signal with a glum value of -0.005 is observed due to the circularly polarized light excitation. Interestingly, the change of the position of the foldamer film leads to an opposite CPL signal with a glum value of +0.028 because the left-handed CPL is absorbed by the foldamer film. The present investigation is crucial in deepening our understanding of the foldamer conformations and promoting the development of novel CPL materials. 

Protein-polymer conjugates are an important class of long-acting proteins, and they have been applied in the diagnosis and treatment of various serious diseases. However, due to the shortcomings of non-specificity, low yield, and potential immunogenicity in current PEGylation method, exploring new, efficient, and mild methods for preparing protein-polymer conjugates with well-defined structures and controllable functions is an important scientific issue in this field. In recent years, our research group and colleagues integrated the two technologies of “site-selective protein modification” and “in situ controlled polymerization”, proposing the concept of “site-selective in situ controlled polymerization (SICP)” to replace traditional PEGylation technology, and made great progress in biomedical applications. The research progress of SICP method is introduced in detail in this talk, which mainly focuses on the background of developing SICP methods, site-selective protein modification, in situ controlled polymerization, and the potential application of novel protein-polymer conjugates synthesized by SICP in the biomedical fields. 

MilliporeSigma (The life science business of Merck KGaA, Darmstadt, Germany) developed and launched DOZN™2.0 in 2017, a unique web-based greener alternative scoring matrix. This quantitative green chemistry evaluator is based on the 12 principles of green chemistry for customers to evaluate their relative greenness of their processes which provide a framework for learning about green chemistry and designing or improving materials, products, processes, and systems. DOZN™2.0 scores products based on metrics for each principle and aggregates the principle scores to derive a final aggregate score. Through the system it is possible to calculate a green score for each substance based on manufacturing inputs, GHS, and SDS data. DOZN™2.0 is flexible enough to encompass a diverse portfolio of products and it has been verified and validated by a third party to ensure best practices are applied. Based on customer feedback, an upgraded version of the tool, DOZN™3.0, launched in December 2024. Through DOZN™3.0, customers now have access to calculate the green scores of their processes and products. DOZN™3.0 keeps data privacy top of mind - allowing customers to score their processes/products in a safe and secure manner. Come learn how to make your science greener using this free, web-based tool provides users with more data so that they are properly equipped to improve their sustainability.

Nanopatterned interfaces enable precise control over surface morphology and chemistry at the nanoscale, offering advanced capabilities in biosensing, molecular capture, and adaptive surface engineering. Their high-aspect-ratio structures enhance film integrity and allow spatially discrete functional domains. When combined with stimuli-responsive polymers, these surfaces can respond dynamically to environmental cues[1]. However, most existing systems incorporate only one type of responsive polymer, limiting their functionality and versatility[2]. Challenges in fabrication and chemical compatibility have hindered the integration of multiple responsive components into a single nanoscale interface. Recent advances in nanolithographic templating and surface-initiated photoinduced electron transfer-reversible addition–fragmentation chain transfer (SI-PET-RAFT) polymerization have enabled the creation of binary-patterned surfaces with independent spatial and chemical control[3]. We constructed a dual-responsive nanopatterned interface by integrating photothermal polypyrrole (PPy) with thermoresponsive poly(EGMEA-co-PEGMEA) brushes[4]. Nanoporous PPy films were prepared via colloidal templating and electrochemical deposition, followed by selective brush growth through SI-PET-RAFT polymerization. This binary system demonstrates the synergistic potential of combining multiple responsive elements within confined nanostructures. It offers a modular platform for multifunctional surfaces with applications in biosensing, targeted capture, and smart biointerfaces.

Adhesives are essential synthetic polymer materials with increasing demand in advanced sectors including renewable energy, consumer electronics, intelligent manufacturing, and sustainable packaging. Traditionally, the adhesion performance of these materials has been enhanced by manipulating intermolecular interactions, such as hydrogen bonding, ion-dipole interactions, coordination bonds, and hydrophobic aggregation, which improve energy dissipation under applied stress. However, these non-covalent interactions are dynamic and sensitive to variables like temperature and strain rate, limiting their effectiveness to specific conditions, and current performance enhancements are reaching a plateau.

In contrast to these intermolecular interactions, the inherent chain and network structures of polymers remain mechanically stable barring degradation, offering a consistent contribution to material performance. Leveraging this characteristic, our research group has concentrated on optimizing polymer topology to create high-performance adhesives. We have developed strategies such as blending polymers with tailored molecular weights, introducing trapped entanglements within polymer networks, and synthesizing hyperbranched polymer architectures to significantly enhance adhesive strength. Our innovative approaches to macromolecular topology aim to overcome the limitations of traditional methods and pave the way for advanced adhesion technologies.

Dynamic covalent chemistry (DCC), exemplified by imine chemistry, has unlocked unprecedented opportunities for designing polymeric materials with tunable structures and multifunctionality. Building upon this foundation, our recent work leverages imine-based dynamic covalent systems to address two critical challenges in materials science: (1) Quaternary Nanocomposites: By incorporating cleavable dynamic covalent bonds at the “root” of polymer-grafted nanoparticles, we achieved repeated grafting, degrafting, and regrafting of polymer brushes on nanoparticle surfaces. This strategy enables the fabrication of nanocomposites with multiple chemically distinct polymer grafts while avoiding phase separation—a breakthrough for modular and adaptive hybrid materials[1]. (2) Water-Degradable Networks: Utilizing a guanidine-mediated Mannich-type reaction[2], we constructed dynamic polymer networks (films and hydrogels) from low-cost reactants (guanidine hydrochloride, aldehydes, and diamines)[3]. These materials exhibit stimuli-responsiveness, autonomous self-healing, and complete degradation in room-temperature water within 30 days—a rare combination of robustness and degradability. The inherent reversibility of dynamic covalent bonds not only facilitates reprocessability but also provides a pathway toward a sustainable future. Our findings highlight how DCC principles can bridge the gap between performance-driven engineering and sustainability. Looking ahead, these works opens avenues for designing “programmable” materials with on-demand degradation kinetics, particularly for transient electronics, eco-friendly packaging, and biomedical devices. By integrating molecular-level dynamism with macroscopic functionality, we envision a new paradigm where advanced materials coexist harmoniously with circular economy principles.

Controlled radical polymerization (CRP) is typically performed under inert conditions, requiring rigorous deoxygenation procedures such as inert gas purging or freeze–pump–thaw cycles, as oxygen acts as an inhibitor by quenching free radicals. To overcome oxygen inhibition, strategies such as enzymatic cascade catalysis have been explored, where molecular oxygen is converted into radicals to initiate polymerization. However, the reliance on enzymes increases system complexity and limits compatibility with hydrophobic monomers due to the aqueous medium requirement. In this work, we present a novel strategy that utilizes oxygen to initiate and regulate polymerization. By leveraging the homolytic substitution reactions between oxygen and trialkylboranes, carbon-based radicals are generated, serving as effective initiators for radical processes. We have successfully applied this oxygen-initiated system to RAFT polymerization and ATRP. Furthermore, we exploit the side reaction where radicals react with oxygen to form peroxy radicals, directly incorporating oxygen as a monomer into the polymer backbone. This approach enables the design of polyperoxides as novel polymers that can act as biological prodrugs, generating reactive oxygen species (ROS) for potential applications such as cancer therapy. This work demonstrates a versatile and innovative use of oxygen in CRP, expanding its utility in both polymerization control and functional material design. 

Advanced smart polymer materials capable of reversible deformation under external stimuli hold significant promise in robotics, soft machines, and flexible electronics. However, their further development is often hindered by complex fabrication processes, low efficiency, and limited functionality of existing actuators. In this work, we present an efficient and mild catalyst-free thiol-yne click polymerization method to fabricate photosensitive polyimide (PI) films. Fluorescent, robust photoactuators with a single-layered Janus structure were then directly obtained via UV-assisted photo-crosslinking of these films. These actuators exhibit reversible responses driven by a pronounced mismatch in expansion between the front and back sides of the films.

By achieving a selective, non-uniform spatial distribution within the PI films, these actuators demonstrate rapid and reversible complex morphing behaviors. Furthermore, the system enables straightforward fluorescent information encryption, reading, and erasure—all using a single UV light source. With robust mechanical properties and strong driving capabilities, the actuators effectively convert light energy into visible motion, even under heavy loads. They also exhibit dynamic leaping through energy storage and release, underscoring their potential for practical applications requiring durability, reliability, and versatility.

Hydrogen atom transfer (HAT) chemistry has emerged as a powerful tool for selective molecular functionalization, finding increasing applications in polymer chemistry to control polymer properties and enable degradation. This study explores the versatility of HAT in two distinct areas of polymer science. First, we investigate the use of photocatalyzed HAT for the synthesis of reversible addition–fragmentation chain transfer (RAFT) agents (CTAs) by modifying various substrates, and evaluate the resulting CTAs in both thermal and photoinduced electron transfer (PET)-RAFT polymerization for controlled polymerization and copolymer synthesis. This approach is then extended to functionalize polycaprolactone (PCL) and polyvinyl acetate (PVAc), enabling the synthesis of graft copolymers. Second, we present a novel strategy to enhance the depolymerization of non-functionalized poly(methyl methacrylate) (PMMA) by enabling in situ activation of the polymer backbone using photoinduced HAT. We demonstrate that disulfide-based RAFT agents, particularly bis(dodecylsulfanylthiocarbonyl) disulfide, can effectively promote depolymerization under mild conditions to generate monomers. In both applications, photocatalysts, including iron(III) chloride (FeCl3), are investigated to promote HAT, leveraging the advantages of mild and efficient radical generation under light irradiation compared to conventional thermal HAT systems. This work highlights the broad potential of HAT chemistry in developing advanced polymer synthesis and degradation strategies

Thin film processing is an emerging technology where the liquid is subjected to centrifugal forces/shear stress or mechanical energy within dynamic thin films on a surface. The vortex fluidic device (VFD) as a paradigm shifts in flow processing, with scalability factored in under the continuous-flow mode of operation of the device, along with its utility for tuning the size, morphology, and properties of materials at the nanoscale dimension. The VFD delivers high shear as a constant form of mechanical energy, with tunable control over the processing. This talk delivers information about the significance of utilizing the VFD to control material structure-property relationships of polymer composites at the nanoscale with emphasis on its high green chemistry metrics [1]. A few case studies have been highlighted in this talk including (1) hyperbranched polymers tune properties of alginate hydrogels [2], (2) fabrication of PVA hydrogel with tunable surface morphologies and enhanced self-healing properties [3, 4], (3) fluorescent hyperbranched polymers [5] and (4) enhancement of mechanical properties and microstructure of biomass-based biodegradable films [6]. 

The intrinsic dynamic feature of mechanically interlocked molecules (MIMs) has attracted great interest from polymer chemists, allowing them to explore various types of mechanically interlocked polymers (MIPs), such as polyrotaxanes and polycatenanes. However, almost all the previously reported methods to afford polyrotaxanes are uncontrolled and therefore unable to deliver materials with well-defined structures and narrow dispersity. Our group has recently developed a new method to synthesize polyrotaxanes in a controlled manner. Through ring-opening metathesis polymerization (ROMP) using a catenane as the selected monomer, we can produce polyrotaxanes with controlled molecular weights and narrow dispersity. The ratio of the threaded rings can also be regulated by the copolymerization of other norbornene-based monomers on account of the broad substrate scope of ROMP. Furthermore, we aim to harness this newly developed method to afford slide-ring networks (by crosslinking movable rings covalently) with a precisely controlled density of crosslinks, which is the key factor in modulating network performance and mechanical properties. This approach will provide access to various polymer networks formed by ROMP that are both tough and stretchable and, most importantly, shed light on the structure-property relationship between movable crosslinks and bulk materials. 

In this talk, recent advances from our group regarding the controlled synthesis of MIPs and our foray into slide-ring materials will be covered. 

The synthesis of sustainable polymers is a hot topic but a challenging issue in the field of polymer chemistry. In this report, we report on the synthesis of polyesters from cationic copolymerization of aldehydes (and acetals)[1-2] with cyclic anhydrides through using a series of catalyst/initiator. Aldehydes and cyclic anhydrides are two important types of oxygen-rich compounds that can also be derived from biomass, and acetals can be derived from diol and formaldehyde. This report presents a new family of alternating aldehydes and cyclic anhydrides through cationic mechanism, including aldehyde (acetal)/cyclic anhydride copolymers with fully alternated sequence, especially, sea water degradable the formaldehyde/cyclic anhydride copolymers with AB/ABB sequence[3], and flame-retardant chloral/cyclic anhydride copolymers [4] will be highlighted. The cationic polymerization is versatile and has successfully synthesized polyesters with new structures, which can potentially be used in the manufacture of plastics and rubbers. At high temperatures, these polymers could be degraded to the initial aldehydes and cyclic anhydrides, and the recovery rate exceeds 90%, thus achieving efficient closed-loop recovery of the monomers. The oxygen-rich polyester synthesized from biomass demonstrates the concept of low-carbon polymers.

Mechanochemistry has emerged as a pivotal strategy for advancing sustainable and green polymer synthesis, addressing critical challenges in reducing solvent waste, energy consumption, and environmental toxicity. At its core lies the fundamental scientific challenge of efficiently coupling mechanical force with controlled radical polymerization mechanisms while developing synergistic strategies to overcome kinetic and thermodynamic limitations. This presentation introduces a groundbreaking approach centered on tandem mechanoactivation, designed to achieve high-efficiency mechanical energy transfer and precise spatiotemporal regulation of multi-component controlled radical polymerization. First, we will elucidate a novel radical generation mechanism driven by tandem mechanoactivation. This process leverages sequential mechanical energy inputs to initiate polymerization at significantly reduced activation energies, establishing a low-energy mechanochemical platform. Remarkably, this system operates efficiently under solvent-free conditions and is inherently air-tolerant, enabling the precise synthesis of well-defined polymers with tailored molecular weights and narrow dispersities—without the need for volatile organic solvents or inert atmospheres.Second, we will present a solventless mechanochemical strategy for controlled copolymerization, specifically resolving persistent kinetic challenges such as component immiscibility and diffusion limitations that plague conventional solution-based reactions. By eliminating solvent-mediated barriers, this approach facilitates the controlled synthesis of functional polymer nanocomposites, integrating nanomaterials (e.g., graphene, cellulose nanocrystals) directly into the polymer matrix. The resulting composites exhibit enhanced functional properties—including mechanical and electromagnetic performance—while aligning with green chemistry principles.

The development of new polymerization methods for preparing functional polymer materials with unique structures and attractive properties is of great significance in both polymer chemistry and materials science. As an important group of functional polymer materials, fused heterocyclic polymers have received extensive attention in different fields. However, traditional synthetic methods toward such polymers normally require limited and expensive fused aromatic substrates, elaborate reaction control, complicated operation procedures, and painful isolation. These synthesis difficulties greatly restrict their accessibility. When it is necessary to introduce multiple functional substituents in complex heterocyclic structure units, the polymer synthesis would be even be more challenging. In contrast, transition metal-catalyzed C-H-activation/annulation polymerizations based on acetylenic monomers offer a facile and efficient way for the synthesis of fused heterocyclic polymers by utilizing inert C-H as potential functional groups. With this strategy, complex fused heterocycles can be generated in-situ in polymer backbones from simple and readily available reactants, showing the advantages of simple operation, high efficiency, high atom economy, etc. The resulting fused heterocyclic polymers generally possess multiple aromatic substituents, which can endow the polymers with good solubility and excellent aggregate-state luminescence properties. This report will introduce our recent work progress on the development of novel C‒H activation/annulation polymerization reactions for the synthesis of multifunctional fluorescent fused heterocyclic polymers, including the stoichiometric two-component polyannulations of internal diynes and aromatics, non-stoichiometric two-component polyannulations of internal diynes and monofunctional aromatics, and cascade C‒H activation/annulation polymerizations. The properties and functionalities of the obtained fused (hetero)cyclic polymers will also be introduced.[1-4] A brief outlook on the future development directions of this field will also be briefly discussed.