Cross-linking Of Polymer Chains Research Articles

Frontier and hot topics in the application of hydrogel in the biomedical field: a bibliometric analysis based on CiteSpace

Hydrogels are formed of crosslinked polymer chains arranged in three-dimensional (3D) networks. These chains have good water-containing capacity and are soft and malleable. Hydrogels have good biocompatibility due to their significant water content, flexible structure, and numerous holes. These characteristics make them analogous to biological tissues. Despite the publication of 8700 literature related to hydrogel biomedical applications in the past 52 years (1973 ~ 2024), studies on the use of hydrogels in biomedicine are few. To gain a comprehensive understanding of their current development status, research trends, and prospects in the biomedical application field, it is imperative to conduct a thorough retrospective analysis. In this study, we employ bibliometric analysis and CiteSpace software to quantitatively and visually analyze articles published in this field. Firstly, we provide a quantitative analysis of authorship and institutional publications over the past 52 years to elucidate the fundamental development status regarding hydrogel biomedical applications. Secondly, we did visual studies on terms that are high-frequency, explosive, keyword clustering, and so on, to understand the directionality and evolution of the main research hotspots during each period. Notably, our findings emphasize that fabricating hydrogels into wound healing-promoting dressings emerges as a prominent hotspot within the application field. We anticipate that this paper will inspire researchers with novel ideas for advancing hydrogel applications in biomedicine.

Efficiently tuning the electrical performance of PBTTT-C14 thin film via in situ controllable multiple precursors (Al2O3:ZnO) vapor phase infiltration

Conjugated polymer-based organic/inorganic hybrid materials become the current research frontier and show great potential to integrate flexible polymers and rigid solid materials, which have been widely used in the field of various flexible electronics and optical devices. In this study, based on the multiple vapor phase infiltration (VPI) process, various precursor molecules (diethylzinc DEZ, trimethylaluminum TMA, H2O) are applied for the in situ modification of PBTTT-C14 films. The conductivity of the PBTTT-C14/Al2O3:ZnO (AZO) film is significantly enhanced, and the maximum value of conductivity is 1.16 S cm−1, which is eight orders of magnitude higher than the undoped PBTTT-C14 thin film. Here, the change of morphologies and crystalline states are analyzed via SEM, AFM, and XRD. And the chemical changes during the VPI process of PBTTT-C14 are characterized through Raman, XPS, and UV–vis. During the AZO VPI process, the formation of new ZnS matrix in the polymer subsurface can generate new additional electron conduction pathways through the crosslinking of polymer chains with inorganic materials, and the addition of Al2O3 can bring about the increase of average grain size of ZnO crystals, which is also benefit to the conductivity increase of PBTTT-C14 thin film. Generally, the synergistic effect between the inorganic and polymer constituents results in the significantly enhancement of the conductivity of PBTTT-C14/AZO thin films.

Cholesterol-Bearing Polysaccharide-Based Nanogels for Development of Novel Immunotherapy and Regenerative Medicine.

Novel functional biomaterials are expected to bring about breakthroughs in developing immunotherapy and regenerative medicine through their application as drug delivery systems and scaffolds. Nanogels are defined as nanoparticles with a particle size of 100 nm or less and as having a gel structure. Nanogels have a three-dimensional network structure of cross-linked polymer chains, which have a high water content, a volume phase transition much faster than that of a macrogel, and a quick response to external stimuli. As it is possible to transmit substances according to the three-dimensional mesh size of the gel, a major feature is that relatively large substances, such as proteins and nucleic acids, can be taken into the gel. Furthermore, by organizing nanogels as a building block, they can be applied as a scaffold material for tissue regeneration. This review provides a brief overview of the current developments in nanogels in general, especially drug delivery, therapeutic applications, and tissue engineering. In particular, polysaccharide-based nanogels are interesting because they have excellent complexation properties and are highly biocompatible.

Hydrogen bonding regulation on phase change in stimuli responsive copolymer aqueous solution

Hydrogen bonding (HB) is vital for the phase transition and physical properties of stimuli responsive copolymers. However, the governing mechanism remains unclear. Herein, we investigated the HB dynamics in a representative thermo-responsive copolymer (PNIPAM-AM) aqueous solution. Three types of HB were identified: polymer-polymer chain (CO:H–N), polymer chain-water molecule (CO:H–O) and water-water molecules (H–O:H–O) by vibrational spectroscopy. Increasing polymer concentration, the H–O:H–O softened and CO:H–O stiffened, leading to the destruction of HB network in water-water clusters. Upon increasing solution temperature, CO:H–O softened while CO:H–N stiffened, resolving the dehydration and cross-linking of polymer chains. Confinement of water molecules in the “cages” (∼ tens to hundreds of micrometers) after sol-gel phase transition was visualized, disclosing the mechanism of water holding capacity of PNIPAM-AM. The correlation of molecule vibration and copolymer microscopic structure was established, contributing to the fundamental understanding of phase behavior and physical properties regulations in stimuli responsive copolymer aqueous solution.

Multi-role conductive hydrogels for flexible transducers regulated by MOFs for monitoring human activities and electronic skin functions.

Metal organic frameworks (MOFs) have garnered significant attention in the development of stretchable and wearable conductive hydrogels for flexible transducers. However, MOFs used in hydrogel networks have been hampered by low mechanical performance and poor dispersibility in aqueous solutions, which affect the performance of hydrogels, including low toughness, limited self-recovery, short working ranges, low conductivity, and prolonged response-recovery times. To address these shortcomings, a novel approach was adopted in which micelle co-polymerization was used for the ex situ synthesis of Zn-MOF-based hydrogels with exceptional stretchability, robust toughness, anti-fatigue properties, and commendable conductivity. This breakthrough involved the ex situ integration of Zn-MOFs into hydrophobically cross-linked polymer chains. Here the micelles of EHDDAB had two functions, first they uniformly dispersed the Zn-MOFs and secondly they dynamically cross-linked the polymer chains, profoundly influencing the mechanical characteristics of the hydrogels. The non-covalent synergistic interactions introduced by Zn-MOFs endowed the hydrogels with the capacity for high stretchability, high stress, rapid self-recovery, anti-fatigue properties, and conductivity, all achieved without external stimuli. Furthermore, hydrogels based on Zn-MOFs can serve as durable and highly sensitive flexible transducers, adept at detecting diverse mechanical deformations with swift response-recovery times and high gauge factor values. Consequently, these hydrogels can be tailored to function as wearable strain sensors capable of sensing significant human joint movements, such as wrist bending, and motions involving the wrist, fingers, and elbows. Similarly, they excel at monitoring subtle human motions, such as speech pronunciation, distinguishing between different words, as well as detecting swallowing and larynx vibrations during various activities. Beyond these applications, the hydrogels exhibit proficiency in distinguishing and reproducing various written words with reliability. The Zn-MOF-based hydrogels hold promising potential for development in electronic skin, medical monitoring, soft robotics, and flexible touch panels.

Einzelkettennanopartikel in der Katalyse

AbstractIn den letzten sechs Jahrzehnten haben sich gefaltete Polymerketten, sogenannte Einzelketten‐Nanopartikel (EKNPs), von dem bloßen Konzept intramolekular vernetzter Polymerketten zu maßgeschneiderten Nanoreaktoren entwickelt. Diese Entwicklung wurde durch eine Vielzahl von Techniken und chemischen Verfahren zur Anpassung und Analyse ihrer Morphologie und Funktion unterstützt. Diese monomolekularen Polymere bieten in einer breiten Palette von Anwendungen ein vielversprechendes Potenzial. In diesem Beitrag diskutieren wir die faszinierenden Fortschritte, die in den letzten Jahren im Bereich der katalytisch aktiven EKNPs erzielt wurden.

Single Chain Nanoparticles in Catalysis.

Over the last six decades folded polymer chains-so-called Single Chain Nanoparticles (SCNPs)-have evolved from the mere concept of intramolecularly crosslinked polymer chains to tailored nanoreactors, underpinned by a plethora of techniques and chemistries to tailor and analyze their morphology and function. These monomolecular polymer entities hold critical promise in a wide range of applications. Herein, we highlight the exciting progress that has been made in the field of catalytically active SCNPs in recent years.

Investigation into the gel substrate fabrication of a novel ammonium amine explosive and its generic properties exploration

Gels from crosslinked polymer chains are promising soft matters which are attracting enormous research interests in applications such as biomedical, sensing, antibiofouling, intelligence and advanced manufacturing. In this work, gels composed of polymer network are used for components stabilization in a novel water-resistant explosive, termed as ammonium amine explosive. The ammonium amine explosive is endowed with water resistance taking advantages of the swelling property of polymer network. Moreover, this ammonium amine explosive is featured by its facile, mild, intrinsically safe and energy saving fabrication method compared to universal explosives’ manufacturing technique which generally includes high temperature or high-speed shearing process. The density and microstructure of the explosive gel substrates is found to be pH dependent. This phenomenon is chemically explained by the crosslinking and foaming reactions of the explosive gel substrates, and further confirmed by water resistance experiments performed on the ammonium amine explosive and the mechanical tests performed on the gel substrates. This work presents a unique application of polymer gel network in a novel engineering explosive, gives a chemical viewpoint into the explosive characterization, and provides a prospective perspective to investigate the other performances and structure of this water-resistant explosives in the future.

Crosslinked polymer-in-salt solid electrolyte with multiple ion transport paths for solid-state lithium metal batteries

Low ionic conductivity and unsatisfactory mechanical properties of the solid polymer electrolytes hinder their applications of in solid-state lithium metal batteries. Herein, we design a polymer-in-salt solid electrolyte (PISSE) with multiple Li+ transport paths and crosslinked polymer chain networks, endowing the PISSE with both high mechanical strength and high ionic conductivity. The optimized PISSE can therefore reach ionic conductivity of 3.03×10−4 S cm−1 (25 °C) and the mechanical strength of 0.811MPa. The percolation model explains that the salt-rich clusters account for the extra fast ion transfer paths; whereas, the crosslinking structure compensates the loss of mechanical strength at high salt concentration. Finally, the in situ polymerization of PISSE promotes the electrode-electrolyte interface compatibility, resulting in the Li//PISSE60%@LiFePO4 cells with 71% (initial capacity: 111.8 mAh g−1) of capacity retention after 800 cycles at 0.5 C. Moreover, the PISSE also exhibits compatibility with high voltage cathode LiFe0.2Mn0.8PO4 cells up to 4.3V. Therefore, this work provides a practical strategy to fabricate stable solid electrolytes for next-generation lithium metal batteries.

Investigating the effect of methacrylic acid on the properties of waterborne epoxy-acrylate core-shell emulsion, film and coating

Waterborne coating has recently become a trend in research, with extensive studies focusing on waterborne epoxy-acrylate (WEA) emulsion. However, the understanding of the role of methacrylic acid (MAA) in the core-shell structure, affecting film and coating performance, is still limited. Here, we investigate the effect of MAA addition on the properties of the WEA core-shell emulsion, film and coating. The WEA core-shell emulsion was synthesized through semi-continuous emulsion polymerization and subsequently cast into WEA film. Two types of crosslinking systems were established by introducing MAA to either the shell layer (interlayer crosslinking) or the core layer (intralayer crosslinking). The interlayer crosslinking provides a high crosslinking density (7.01 × 10−4 mol cm−3), involving the crosslinking of polymer chains between the core and shell layers. Consequently, the film has a compact structure and high modulus (489 MPa) but low elongation at break (3.20 %). Conversely, the intralayer crosslinking has a low crosslinking density (1.59 × 10−4 mol cm−3). Hence, the film has a loose structure and low modulus (0.38 MPa) but high elongation at break (225 %). This occurs because it involves crosslinking with the polymer chains within the same layer, resulting in reduced compatibility between the layers. The inclusion of MAA enhances the clarity in discerning two glass transition temperatures (Tg). Lastly, the stability (shelf-life) of the WEA emulsion remains unaffected by the MAA, with the decisive factor being the presence of the oxirane ring in the Epoxy (EP). We believe that this finding can significantly contribute to a better understanding of the role of MAA in crosslinking systems within WEA core-shell coatings for researchers.

Organosilicon copolymers containing triazole and triethoxysilyl groups as the basis for promising functional hydrophobic materials

New functional heat-resistant poly (1-vinyl-1,2,4-triazole-co-triethoxyvinylsilane) (poly (VT-co-TEVS)) copolymers of various compositions containing triazole and triethoxysilyl groups in the side chains were synthesized by radical copolymerization. Elemental analysis, Fourier transform infrared spectroscopy, NMR spectroscopy, gel permeation chromatography, dynamic light scattering, scanning electron microscopy, thermogravimetric analysis, and differential scanning calorimetry were used to study the composition and structure of poly (VT-co-TEVS) copolymers. The weight average molecular weight of the copolymers varies from 21 to 174 kDa. The reactivity ratios of comonomers in copolymerization (rVT = 4.004 and rTEVS = 0.227) indicate the high reactivity of VT. The resulting copolymers exhibit high thermal stability up to 270 °C. Modification of flexible chain poly (VT-co-TEVS) copolymers was carried out using hydrolytic polycondensation of triethoxysilyl groups. Monitoring of the hydrodynamic diameters of the synthesized copolymers showed intermacromolecular crosslinking of polymer chains due to the formation of Si–O–Si siloxane bonds. Based on spatially cross-linked polyorganosiloxanes containing a functional 1,2,4-triazole fragment, hydrophobic heat-resistant polymeric materials were obtained.

Effect of polymer molecular weight on the long-term process stability of crosslinked polybenzimidazole organic solvent nanofiltration (OSN) membranes

The importance of polymer molecular weight on the long-term performance of polybenzimidazole (PBI) membranes in organic solvents was investigated. PBI membranes were manufactured from two different polymer molecular weights: the standard molecular weight of PBI polymer, used almost universally across literature for organic solvent stable membranes (∼27,000 g mol-1), and an untested ∼ two-fold higher molecular weight (∼60,000 g mol-1). After crosslinking, all PBI membranes were chemically and mechanically stable. However, during continuous long-term pressurised filtration in DMF, the standard molecular weight PBI membranes suffered slow permeance decline over time. This was attributed to rearrangement of the crosslinked polymer chains. Increasing the extent of crosslinking reduced the rate of membrane permeance decline but did not provide a fully process stable membrane. Using a higher molecular weight PBI, and a similar extent of crosslinking, resulted in a membrane with constant permeance and excellent process stability, even during continuous DMF filtration at 120 °C. This was attributed to the increased interchain interactions and entanglement in the high molecular weight polymer, which reduced the rate of chain rearrangement and compaction. This work demonstrates the importance of polymer molecular weight for reducing membrane compaction and providing process stability in organic solvents.

Design and preparation of novel silicon rubber with homogeneous crosslinking network and its application in high-performance SR/EPDM blend

Due to the low intermolecular force, silicone rubber (SR) processes weak mechanical properties and it’s difficult to blend with other conventional rubbers, which limits its application. Herein, a series of novel SRs with evenly distributed and different types of crosslinking groups were synthesized and cured to SR blends. The novel SRs promote the uniform distribution of crosslinking points during vulcanization, which contributes to the increase in both tensile strength and elongation at break. Besides, the introduction of different types of crosslinking groups decreases vulcanization speed as well as increases the flexibility of the bridge between two crosslinked polymer chains, resulting in the elongation at break as high as 1143%, which is twice higher than commercial SR. The novel SRs were subsequently blended with ethylene-propylene-diene rubber (EPDM) to prepare high-performance blends. Compared with the commercial SR/EPDM blend, the matching vulcanization resulted in an increase in the tensile stress and elongation at break by 27.6% and 35.3%, respectively. In addition, dielectric strength increases from 34.2 to 40.8 kV/mm for SEP-VCH. Our work provides a new strategy to prepare SR with high mechanical properties and improve the properties of SR/EPDM blend without the addition of a compatibilizer, thus extending the application of SR.

Theoretical study on the pyrolysis process of POSS nanocomposites based on the molecular vibration frequency

Identifying the factors that determine the thermal stability of polymer nanocomposites with inorganic fillers is vital. This study investigates how the modulation of polyhedral oligomeric silsesquioxanes (POSSs) affects the polymer-chain thermodynamics, using a multiscale analysis that integrates reactive molecular dynamics, first-principles calculations, and classical vibrational dynamics. The intramolecular energy transfer mechanism depending on the polymer-chain vibration frequency and covalent structure was analyzed for the entire pyrolysis process. The results revealed that the low-frequency vibration of POSS is key for the superior nanocomposite thermal stability. The dual frequency of the C–Si stretching mode directly contributes to the collection and dissipation of the thermal energy contained in the crosslinked polymer chain. The ability to block exothermic reaction pathways under pyrolysis conditions was also identified. This result elucidates the mechanism by which inorganic fillers perturb the thermodynamics and thermochemistry of polymer matrices as energy transfer within molecular chains.

Polymer-Based Hydrogel Loaded with Honey in Drug Delivery System for Wound Healing Applications.

Excellent wound dressings should have crucial components, including high porosity, non-toxicity, high water absorption, and the ability to retain a humid environment in the wound area and facilitate wound healing. Unfortunately, current wound dressings hamper the healing process, with poor antibacterial, anti-inflammatory, and antioxidant activity, frequent dressing changes, low biodegradability, and poor mechanical properties. Hydrogels are crosslinked polymer chains with three-dimensional (3D) networks that have been applicable as wound dressings. They could retain a humid environment on the wound site, provide a protective barrier against pathogenic infections, and provide pain relief. Hydrogel can be obtained from natural, synthetic, or hybrid polymers. Honey is a natural substance that has demonstrated several therapeutic efficacies, including anti-inflammatory, antibacterial, and antioxidant activity, which makes it beneficial for wound treatment. Honey-based hydrogel wound dressings demonstrated excellent characteristics, including good biodegradability and biocompatibility, stimulated cell proliferation and reepithelization, inhibited bacterial growth, and accelerated wound healing. This review aimed to demonstrate the potential of honey-based hydrogel in wound healing applications and complement the studies accessible regarding implementing honey-based hydrogel dressing for wound healing.

Neutron Reflectometry Analysis of Condensed Water Layer Formation at a Solid Interface of Epoxy Resins Under High Humidity.

Water absorbed by epoxy resins from a humid atmosphere considerably influences their structure and properties. Examining the effects of absorbed water on epoxy resins at their interfaces with solid substrates is crucial because of their adhesive applications in various fields. The spatial distribution of absorbed water in epoxy resin thin films under high humidity was investigated in this study by neutron reflectometry. Water molecules were found to accumulate at the SiO2/epoxy resin interface after exposure at a relative humidity of 85% for 8 h. The formation of an ∼1-nm-thick condensed water layer was observed, and the thickness of this layer varied with curing conditions of epoxy systems. Furthermore, water accumulation at the interface was noted to be affected by high-temperature and high-humidity environments. The formation of the condensed water layer is presumed to be related to the features of the polymer layer near the interface. The construction of the interface layer of epoxy resin would be affected by the interface constraint effect on the cross-linked polymer chain during the curing reaction. This study provides essential information for understanding the factors influencing the accumulation of water at the interface in epoxy resins. In practical applications, the process of improving the construction of epoxy resins near the interface would be a reasonable solution to resist water accumulation in the interface.

Thermoresponsive Dendronized Microgels through In Situ Cross-Linking Polymerization to Exhibit Enhanced Confinement for Solvatochromic Dyes

Polymeric microgels form a class of promising materials for various applications based on their highly tunable swelling and cooperative interactions between the cross-linked polymer chains. Here, we report on a convenient route for the fabrication of polymeric microgels through in situ cross-linking polymerization of thermally collapsed macromonomers carrying 3-fold dendritic oligoethylene glycol (OEG) pendants, affording thermoresponsive dendronized microgels with intriguing microconfinement. This methodology has been proven to be versatile and can be used to prepare intelligent microgels through homopolymerization of thermoresponsive dendronized macromonomers, or via copolymerization with either hydrophobic or hydrophilic, and dendronized or nondendronized comonomers. The thermoresponsive microgels of uniform sizes undergo shrinking or swelling by changing the temperature above or below their phase transition temperatures and thus exhibit tunable microconfinement to encapsulated solvatochromic dye molecules. This outstanding capacity for confinement by the microgels is compared to linear copolymers with or without dendritic architectures and is proposed to originate from both dendritic crowding effects and cooperative interactions between polymer chains within the network. This remarkable feature of microconfinement opens a new era for microgels to reversibly encapsulate and protect guest molecules and provides a platform to manipulate the functions of the encapsulated guests through external stimuli.

Generalized section–section interaction potentials in the geometrically exact beam theory: Modeling of intermolecular forces, asymptotic limit as strain-energy function, and formulation of rotational constraints

The present contribution proposes a universal framework to formulate generalized section–section interaction potentials (SSIP) within the geometrically exact beam theory. By exploiting the fundamental kinematic assumption of undeformable cross-sections, an objective (i.e., frame-invariant) description of SSIPs via a minimal set of six (translational and rotational) relative coordinates, either in spatial or in material form, is proposed. Based on work-pairing, work-conjugated section–section interaction forces and moments, either in spatial or in material form, are identified that can be consistently derived from a variational principle. Interestingly, it is shown that hyperelastic stored-energy functions relating the deformation measures and stress-resultants of the well-known geometrically exact Simo–Reissner beam theory can also be identified as SSIPs when considering the asymptotic limit of small relative distances and rotations between the interacting cross-sections. Moreover, the proposed variational problem formulation is demonstrated to be of a very general nature, thus allowing for the formulation of translational and rotational constraints between arbitrarily oriented cross-sections based on either a penalty or a Lagrange multiplier potential. Possible applications include fiber-based structures and materials in technical and biological systems, where the proposed approach allows to model short- or long-ranged inter-molecular (e.g., electrostatic, van der Waals or repulsive steric) interactions between fibers in geometrically complex arrangements and to formulate translational and rotational coupling constraints between different fibers (e.g., cross-linked polymer chains) or between fibers and a matrix phase (e.g., fiber-reinforced composites).

Main approaches of biofilm formation in composite resins: a concise systematic review

Introduction: Composite resins are widely used in clinical dental practice to restore the structure lost by caries and dental defects, achieving aesthetic and functional results. Failures in the photoactivation process can cause problems in the mechanical resistance to wear in regions of direct occlusal contact on the restorative material. This occurs due to the reduction in the degree of conversion of monomers into polymers, compromising the clinical performance of the composite resin. Polymerization shrinkage leads to microleakage of the restoration, leading to staining and the development of bacterial biofilms. Objective: It was to carry out a systematic review of the main scientific evidence of biofilm formation on composite resin veneers, identifying potential predictors, as well as proposals to mitigate this problem. Methods: The systematic review rules of the PRISMA Platform were followed. The search was carried out from December 2022 to March 2023 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases, using articles from 2015 to 2022. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed accordingly, according to the Cochrane instrument. Results and Conclusion: A total of 125 articles were found, 25 articles were evaluated and 20 were included and developed in this systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 10 studies with a high risk of bias and 70 studies that did not meet GRADE. It was concluded that the surface properties of resin-based composite materials, as well as surface treatments, can strongly affect bacterial adhesion and biofilm formation. In addition, scientific evidence highlights that cariogenic biofilm formation can alter the surface properties of materials, thus stimulating bacterial adhesion and biofilm formation. Photoactivation allows the curing and crosslinking of polymer chains, essential for the clinical longevity of the composite resin. Insufficient photoactivation culminates in marginal microleakage in restorations and biofilm accumulation on surfaces exposed to the oral environment.

Commercial Gel-Type Ion Exchange Resin Enables Large-Scale Production of Ultrasmall Nanoparticles for Highly Efficient Water Decontamination

• Gel-type anion exchange resin enables large-scale production of sub-5 nm particles. • The nanocomposites are millimetric beads applicable in flow-through systems. • Sub-5 nm HFO exhibit >3 times As(III/V) adsorption capacities than 17 nm HFO. • Adsorption capability is fully refreshed for cyclic use by using NaOH-NaCl solution. • The nanocomposite column produces 4800 BV clean water from simulated groundwater. Nanotechnology presents innovative solutions in advanced water treatment; however, its application is limited by the challenging large-scale production of ultrasmall (< 5 nm) nanoparticles (NPs) with extraordinary decontamination reactivity and the difficulty of handling such tiny NPs in engineering. To address these challenges, we propose a straightforward route for synthesizing ultrasmall NPs using the commercial gel-type anion exchange resin N201 as the host. N201 is a millimeter-scale poly(styrene- co -divinylbenzene) bead modified with quaternary ammonium groups. Nanoparticles of hydrated ferric oxide (HFO), hydrated manganese oxide (HMO), cadmium sulfide (CdS), and zero-valent iron (ZVI) were obtained through simple impregnation-precipitation in N201, and all of the NPs possessed an ultrasmall size of sub-5 nm. A pilot-scale production assay indicated that the synthetic system could be enlarged proportionally to prepare massive sub-5 nm HFO. Regarding the underlying mechanism, each N201 bead contained a continuous water phase, allowing the rapid diffusion of the reactants (7 s for diffusion from the bead surface to the center), resulting in burst nucleation to produce ultrasmall NPs with a narrow size distribution. Moreover, the crosslinked polymer chains provided a confined space (< 5 nm diameter) to prevent the excessive growth of the formed NPs. Owing to the millimetric N201 host, the resultant nanocomposite can be applied in flow-through systems. The batch and column adsorption assays demonstrate the dramatically enhanced adsorption performance of the ultrasmall HFO toward As(III/V) than the ∼17 nm analogs. This study can advance the widespread use of nanotechnology in practical water treatment.