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The segmental dynamics of bottlebrush polymers with a stiff backbone and flexible side chains has been studied. The segmental relaxation time of side chains attached to a flexible backbone follows the same trend as linear polymers, an increase with the increasing molecular weight, but is slowed down compared to their linear counterparts. Theoretical work predicts a reversal of the molecular weight dependence of the relaxation time for stiff backbones. As a model for a stiff-g-flexible system, bottlebrushes with poly(norbornene) backbone and poly(propylene oxide) side chains, PNB-g-PPO, at a uniform grafting density have been synthesized and characterized with quasi-elastic neutron scattering. Indeed, the anticipated reversed dynamics was found. Increasing the side chain length decreases the segmental relaxation time. This indicates the importance of the characteristics of the grafting site beyond a simplified picture of an attached side chain. The mean square displacement shows a similar trend with longer side chains exhibiting a larger displacement. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are conducted to systematically investigate the insertion of spherical nanoparticles (NPs) in polymer brushes as a function of their size, strength of their interaction with the polymers, polymer grafting density, and polymer chain length. For attractive interactions between the NPs and the polymers, the depth of NPs' penetration in the brush results from a competition between the enthalpic gain due to the favorable polymer–NP interaction and the effect of osmotic pressure resulting from displaced polymers by the NP's volume. A large number of simulations show that the average depth of the NPs increases by increasing the strength of the interaction strength. However, it decreases by increasing the NPs' diameter or increasing the polymer grafting density. While the NPs' effect on the polymer density is local, their effect on their conformations is long-ranged and extends laterally over length scales larger than the NP's size. This effect is manifested by the emergence of laterally damped oscillations in the normal component of the chains' radius of gyration. Interestingly, we found that for high enough interaction strength, two NPs dimerize in the polymer brush. The dimer is parallel to the substrate if the NPs' depth in the brush is shallow. However, the dimer is perpendicular to the substrate if the NPs' are deep in the brush. These results imply that polymer brushes can be used as a tool to localize and self-assemble NPs in polymer brushes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Aluminum nanoparticles (Al NPs) have significant potential applications in various fields due to their unique LSPR. Significant advancements have been achieved in controlling the size and morphology of Al NPs. However, the efficient modification of Al NPs with polymers has not been implemented. Herein, we report a facile and efficient free‐radical polymerization induced grafting‐to (FRPIGt) method for grafting polymer chains onto Al NPs. By optimizing polymerization conditions, we were able to achieve a polymer brush layer with a weight loss fraction of up to 43.3%, which was higher than those of other polymers with carboxyl or primary amine end groups. Moreover, a broad range of vinyl monomers, including styrene, methacrylate, and methyl methacrylate, can be applied using the FRPIGt method to modify Al NPs. In addition, the FRPIGt method can be extended to photoinduced organocatalyzed atom‐transfer‐radical polymerization. This work paves a new path for the preparation of a wide range of polymer‐functionalized Al NPs and their polymer composites to be utilized in various fields. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Aluminum nanoparticles (Al NPs) have significant potential applications in various fields due to their unique LSPR. Significant advancements have been achieved in controlling the size and morphology of Al NPs. However, the efficient modification of Al NPs with polymers has not been implemented. Herein, we report a facile and efficient free‐radical polymerization induced grafting‐to (FRPIGt) method for grafting polymer chains onto Al NPs. By optimizing polymerization conditions, we were able to achieve a polymer brush layer with a weight loss fraction of up to 43.3%, which was higher than those of other polymers with carboxyl or primary amine end groups. Moreover, a broad range of vinyl monomers, including styrene, methacrylate, and methyl methacrylate, can be applied using the FRPIGt method to modify Al NPs. In addition, the FRPIGt method can be extended to photoinduced organocatalyzed atom‐transfer‐radical polymerization. This work paves a new path for the preparation of a wide range of polymer‐functionalized Al NPs and their polymer composites to be utilized in various fields. [ABSTRACT FROM AUTHOR]

The increasing water pollution problem poses a demand for oil–water separation materials, but preparing separation materials with high efficiency and excellent durability remains a great challenge. In this work, we use a diblock polymer brush of polydimethylsiloxane (PDMS) and poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA) based on cotton fabric to prepare oil–water separation membranes with high efficiency, good durability, and intelligent self‐repairing properties. Lubricating PDMS brushes reduces the fouling adhesion due to its low surface energy and high flexibility. pH‐responsive PDMAEMA brushes provide good hydrophobicity and an intelligent self‐repairing effect. The prepared Co‐PDMS‐PDMAEMA has high oil flux (>30,000 L m−2 h−1) and high separation efficiency (>99%) even after 10 cycles and its surface character can be recovered under acidic conditions. Overall, the modified cotton fabric made by such a versatile technique is promising in oil–water separation. [ABSTRACT FROM AUTHOR]

The current study utilized a green synthesis where microwave-assisted free radical technique was applied for economical synthesis of a novel biocompatible polymethyl methacrylate grafted moringa gum amphiphilic graft copolymer, focusing on optimization based on percentage yield, percentage grafting, and intrinsic viscosity was performed, and analytical characterizations confirmed successful grafting. The copolymer demonstrated surfactant-like properties, as evidenced by the determined critical micelle concentration (CMC). Evaluation of its impact on poorly water-soluble drugs, simvastatin, and metronidazole benzoate, revealed efficient release within 60 min. Safety assessments, including In vitro assessments like hemocompatibility, bactericidal activity, fish toxicity, and in vivo evaluations such as oral toxicity, and wound repair studies and cell toxicity studies indicated the safety profile of prepared graft copolymer and explored its potential as a biopolymer for pharmaceutical delivery and tissue regrowth platform. [ABSTRACT FROM AUTHOR]

The purpose of the current research study was to formulate and evaluate a fenugreek (FG) and agarose (AG) base hydrogel exploiting pH-responsive attributes and colon targeting of 5-fluorouracil (5-FU). A novel 5-FU loaded fenugreek (FG) and agarose (AG) base hydrogel was formulated via free radical polymerization by employing N', N'methylene bisacrylamide (MBA) as a crosslinker and methacrylic acid as a monomer. The influence of substrate concentrations (FG, AG, MBA, and MAA) was studied on the swelling index, sol–gel fraction, and drug release rate (%). It was also evaluated that as the concentration of fenugreek and agarose increases, drug release increases to 94.35 ± 0.34 (%) at pH 7.4 and 13.34 ± 0.34 (%) at pH 1.2. However, an increase in MAA concentration further leads to an increase in swelling, 95.87 ± 0.23 at pH 7.4 and 14.35 ± 0.74 at pH 1.2. Moreover, MBA concentration could significantly and directly influence the swelling of hydrogels owing to the variation of crosslinking density. An increase in MBA concentration results in a significant decrease in swelling. Fourier transform infrared spectroscopy (FTIR) depicted the grafting of polymers (FG and AG) and monomers (MAA). Thermal behavior showed that the formulated nexus protects the drug and substrate from degradation. The X-ray diffraction analysis (XRD) revealed that the entrapment of the drug within the nexus mimicked its crystalline behavior. The scanning electron microscope (SEM) elucidates the porous, rough, irregular, and asymmetric nature of the nexus. Toxicity studies showed that the best-selected optimized formulated nexus (F9) is biocompatible, non-toxic, and promising for targeted delivery of 5-FU for curing colorectal cancer. [ABSTRACT FROM AUTHOR]

Interface‐stabilizing polymers are frequently used in commercial applications to provide long‐lasting dispersions of colloids in liquid media. Dispersing high concentrations of pigments in aqueous solution can be particularly challenging. Here, we present a novel, fully hydrophilic dispersing agent system for carbon black (CB) pigments based on partially hydrolyzed poly(N‐vinylamides). These highly water‐soluble polymers adsorb onto CB through specific interactions between the polymer and surface‐bound moieties, rather than the hydrophobic effect. They participate in hydrogen bonding, ion–dipole interactions and can be partially positively charged to engage in ion pair formation, providing strong surface affinity. Dispersants are synthesized using free radical copolymerization of N‐vinylform‐ and ‐acetamide, acidic hydrolysis, and subsequent PEGylation. Molecular water solubility of the synthesized polymers is confirmed by using fluorescence spectroscopy. Highly concentrated CB dispersions are prepared in acidic, neutral, and basic media, which we identify to strongly affect the interactions between polymer and CB. The stability of CB dispersions is analyzed using ultracentrifugation and thermogravimetric analysis. The presented polymers are able to provide significantly more stable dispersions than a commercial reference product, showcasing the suitability of poly(N‐vinylamines) as potent CB dispersing agents. [ABSTRACT FROM AUTHOR]

Acrylamide polymers are typically used in industrial and healthcare sectors as thickening agents; however, their thickening capabilities rely mainly in their molecular mass. A versatile and simple strategy to improve their performance is the copolymerization with specific monomers or their chemical modification with structures like dendritic or hyperbranched molecules. This study introduces a novel acrylamide‐acrylic acid polymer grafted with minor proportions (≤4.0 wt%) of Boltorn H30, a hyperbranched polyester monomer. The incorporation of Boltorn H30 aims to exploit the hyperbranched architecture's impact on the viscosity and rheological behavior of polymer solutions. Polymers with 0.4 and 4.0 polyester wt% characterized by several analytical techniques displayed improved viscosity in aqueous solution compared against the parent poly(acrylamide‐co‐acrylic acid). Results revealed that while the molecular mass distribution changed between 20% and 94%, the thickening capabilities significantly improved with increments of 2.7 and 3.8 times compared to that of the original polymers. These findings demonstrate that even with a minimal incorporation of hyperbranched polyesters, the abundance of hydroxyl groups fosters extensive hydrogen bonding, resulting in enhanced viscosity properties of the polymer. [ABSTRACT FROM AUTHOR]

AbstractWax precipitation and deposition are challenging hurdles in pipeline transportation of waxy crude oil. This study focuses on transforming SiO2, Laponite, and montmorillonite particles into hydrophobic particles through polymer grafting. Chemical structure analysis and grafting ratio calculation were performed. Through thermogravimetric analyzer (TGA) test, Laponite showed the highest grafting ratio. The effects of adding nanocomposites, TDA-2024-22, and commercial pour point depressants on the rheological behavior and wax crystallization behavior of African crude oil were compared. Addition of the nanocomposite PDA-22@SiO2 to crude oil, reduced the viscosity by 85.6% at 20 °C and the thixotropy by 60.2%. Wax crystal size decreased in the order of PDA-22@SiO2, PDA-22@Laponite, KS-10, TDA2024-22, and PDA-22@MMT. The pour point decreased by 6 °C with PDA-22@ SiO2 particles but only 3 °C with Laponite and montmorillonite composites. Spherical nanocomposites are promising flow improvers for waxy crude oil. [ABSTRACT FROM AUTHOR]

Natural polysaccharides can serve as carriers of genes owing to their intrinsic biocompatibility, biodegradability, and low toxicity. Additionally, they can be easily chemically modified, e.g., through grafting, leading to hybrid synthetic–biological copolymers with additional functionalities. In this work we report on the electrostatic interaction between a chitosan-g-poly(N-isopropylacrylamide) (Chit-g-PNIPAM) copolymer and DNA macromolecules of different lengths (i.e., 50 and 2000 bp), towards the construction of polyplexes that can serve as potential gene delivery systems. At the basic science level, the work aims to elucidate the effects of DNA length on the structural and physicochemical properties of the thermoresponsive hybrid macromolecular assemblies. The protonated amino groups on the chitosan backbone enable electrostatic binding with the anionic phosphate groups of the DNA molecules, while the PNIPAM side chains are expected to impart thermoresponsive properties to the formed polyplexes. Different amino to phosphate group (N/P) mixing ratios were examined, aiming to produce stable dispersions. The physicochemical properties of the resulting polyplexes were investigated by dynamic and electrophoretic light scattering (DLS and ELS), while their morphology was studied by scanning-transmission electron microscopy (STEM). Moreover, their response to changes in temperature and ionic strength, as well as their stability against biological media, was also examined. Finally, the binding affinity of the copolymer towards DNA was evaluated through fluorescence spectroscopy, using ethidium bromide quenching assays, while infrared spectroscopy was used to investigate the structure of the incorporated DNA chains. [ABSTRACT FROM AUTHOR]

Research into sustainable packaging materials has gained increasing importance due to the pressing environmental concerns related to plastic waste. The present study focused on developing a sustainable paper coating based on modified natural rubber (NR) latex filled with gelatin (GT). The graft copolymer latex of NR and poly(vinylbenzyl chloride) bearing quaternary ammonium groups, abbreviated as NR-g-QPVBC, was first synthesized. GT was then incorporated into the latex, and the combination of these materials resulted in a heat-sealable film with good tensile properties and a water barrier. The ionic crosslinking of the latex film was achieved by the reaction with ethylenediaminetetraacetic acid (EDTA). Heat-sealing studies of the NR-g-QPVBC latex film filled with GT (NR-g-QPVBC/GT) revealed its heat-sealability at 160 °C. Scanning electron microscope (SEM) analysis further confirmed the diffusion of the chains across the interface during heat sealing. Dip coating was a method for depositing latex film on kraft paper. The paper coated with the NR-g-QPVBC/GT latex showed a significant increase in dry and wet-tensile strength compared to the uncoated paper. The sealing process was optimized to achieve a heat-seal strength of 755.31 N/m at a dwell time of 3 s and a temperature of 160 °C. The research's practical application was demonstrated by transforming the coated paper into various heat-sealable bags using a handheld bag sealer. [ABSTRACT FROM AUTHOR]

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The polymer grafted materials are frequently used in antifouling and oil–water separation, while the microscopic mechanism of liquid slippage on this surface remains unclear. This study uses molecular dynamics (MD) simulations to explore the structure and transport of oil (n‐hexadecane) on polydimethylsiloxane (PDMS) grafted surface as a function of grafting density. Simulation results indicate that PDMS chain structure undergoes a transition from liquid‐like to solid‐like structure when the grafting density increases. As a result, the entanglement between the PDMS and n‐hexadecane is also weakened. The direct consequence of this structural change is that the slip length of n‐hexadecane shows a non‐monotonic dependence on the grafting density, and a maximum slip length appears at intermediate grafting density. Further analysis indicate that the slip length also increases as the applied shear rate increases, which facilitates the transport of fluid at the grafted surface. These simulation results illustrate the subtle interplay between polymer–alkane interface structure and the transport property of the fluids, which are consistent with recent experimental studies, and will be helpful for rational design of polymer grafted materials in separation technologies. [ABSTRACT FROM AUTHOR]

The rewritable wearables based on photochromism have emerged as attractive candidates in inkless printing applications. Among various photochromic materials, polyoxometalates have great potential for rewritable wearables, with major advantages in fast response upon UV irradiation, long‐term photochemical stability, and excellent fatigue resistance. However, the development of rewritable wearables based on polyoxometalates is limited by low combining fastness, weak stability, and poor scalability. Here, a scalable strategy is reported to fabricate an ideal rewritable wearable based on fundamental charge balance mechanism. The pristine cotton substrate is grafted by cationic polymer brushes to incorporate photochromic phosphomolybdic acid (PMoA) anions through electrostatic attraction, and then the cationic surfactants with alkyl chains are introduced to encapsulate the PMoA anions to achieve charge balance subsequently. The resultant rewritable wearables display the long‐awaited properties, such as high color contrast, favorable reversibility (>10 cycles), long color retention (>15 days) and high stability against detergent and sweat (pH 6.5–8.0) during repeated washing (50 cycles) and wearing. As a demonstration, a rewritable T‐shirt is scalably fabricated, and excellent antibacterial activity and biocompatibility are demonstrated as well, which is expected to be a sustainable solution for regular fabric printing in household products and public display. [ABSTRACT FROM AUTHOR]

Post-traumatic tendon adhesions significantly affect patient prognosis and quality of life, primarily stemming from the absence of effective preventive and curative measures in clinical practice. Current treatment modalities, including surgical excision and non-steroidal anti-inflammatory drugs, frequently exhibit limited efficacy or result in severe side effects. Consequently, the use of anti-adhesive barriers for drug delivery and implantation at the injury site to address peritendinous adhesion (PA) has attracted considerable attention. Electrospun nanofiber membranes (ENMs) have been extensively employed as drug-delivery platforms. In this study, we fabricated a polylactic acid (PLA)–dipyridamole (DP)-graft copolymer ENM called PLC-DP. This membrane exhibits enzyme-sensitive features, allowing more controlled and sustained drug release compared with conventional drug-loaded ENMs. In experiments, PLC-DP implantation reduced tissue adhesion by 47 % relative to the control group while not adversely affecting tendon healing. Mechanistically, PLC-DP effectively activates the FXYD domain containing ion-transport regulator 2 (FXYD2) protein, thereby downregulating the fibroblast-transforming growth factor beta (TGF-β)/Smad3 signaling pathway. PLC-DP leverages the anti-adhesive properties of DP and the enzyme-sensitive characteristics of graft copolymers, providing a promising approach for the future clinical treatment and prevention of PA. Peritendinous adhesions (PA) are a common and disabling condition that seriously affects the prognosis and quality of life of post-trauma patients. Current treatments often have limited efficacy or severe side effects, leaving a serious gap in clinical practice. We developed a significant biomaterial, poly(lactic acid)-dipyridamole graft copolymer electrospun nanofibrous membrane (PLC-DP), specifically for PA inhibition. In addition, this study uniquely combines dipyridamole, an anti-adhesive agent, and enzyme-sensitive copolymers in electrospun nanofibrous membrane. Unlike conventional drug-loaded electrospun nanofibrous membranes, PLC-DPs have enzyme-sensitive drug properties that allow for sustained drug release on demand. Our experiments showed that implantation of PLC-DP was effective in reducing tissue adhesions by 47 % without affecting tendon healing. We elucidated the mechanism behind this phenomenon, suggesting that PCD activates FXYD2 to inhibit TGF-β-induced expression of Col III, which is a key factor in PA development. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose nanocrystal (CNC)‐reinforced composites are gaining commercial attention on account of their high strength and sustainable sourcing. Grafting polymers to the CNCs in these composites has the potential to improve their properties, but current solution‐based synthesis methods limit their production at scale. Utilizing dynamic hindered urea chemistry, a new method for the melt‐functionalization of cellulose nanocrystals has been developed. This method does not require toxic solvents during the grafting step and can achieve grafting densities competitive with state‐of‐the‐art solution‐based grafting methods. Using cotton‐sourced, TEMPO‐oxidized CNCs, multiple molecular weights of poly(ethylene glycol) (PEG) as well as dodecane, polycaprolactone, and poly(butyl acrylate) were grafted to the CNC surface. With PEG‐grafted nanoparticles, grafting densities of 0.47 chains nm−2 and 0.10 chains nm−2 were achieved with 2000 and 10,000 g mol−1 polymer chains respectively, both of which represent significant improvements over previous reports for solution‐based PEG grafting onto CNCs. [ABSTRACT FROM AUTHOR]

The use of graft copolymers as surfactants offers a promising approach to enhance the interfacial properties of polymer blends or fluid blends. The effectiveness of these copolymers is closely related to their topologies. In this study, we employed dissipative particle dynamics (DPD) simulations to investigate the interfaces in incompatible A/B homopolymer blends with graft copolymer AB. In particular, we kept the molecular weights of the "A4B4 series" and "A8B8 series" copolymers constant but varied their architecture. The results show that the "A4B4 series" copolymers exhibit greater efficacy in reinforcing the interface (reduce interfacial tension), as compared to the "A8B8 series". The reduction in interfacial tension achieved by the diblock copolymer is comparatively lower than that achieved by the graft copolymer. Among the various graft copolymers studied, it has been observed that A1A1[B2]A2[B2]/a-S3 graft copolymers exhibit the highest efficiency in reducing interfacial tension. As the graft copolymer A1A1[B2]A2[B2]/a-S3 concentration varies from 0.05 to 0.15, a notable inverse relationship between the degree of copolymer enrichment at the central region of the interface and the corresponding interfacial tension was observed. Specifically, an increase in the concentration of A1A1[B2]A2[B2]/a-S3 graft copolymers led to a discernible decrease in interfacial tension. Due to the saturation of the interface at ccp = 0.15, upon increasing the concentration of the graft copolymers A1A1[B2]A2[B2]/a-S3 from 0.15 to 0.2, the added copolymers mainly enriched in the homopolymer phase. As a result, there is an absence of further reduction in interfacial tension. These studies allow us to predict the reduction in interfacial tension produced by a wide variety of copolymers and thereby permit a rational design of effective compatibilizers. [ABSTRACT FROM AUTHOR]

Objective: Preparation of protein–polysaccharide complexes allows to modulate practically significant characteristics of both components, thereby increasing not only the practical potential of the resulting structures, but also contributing to our understanding of the features of their interactions. Thus, the aim of this work was to study the structural and functional features of the complexes of cysteine proteases (bromelain, papain and ficin) with a graft copolymer of chitosan with poly(N,N-dimethylaminoethyl methacrylate) (CTS–DMAEMA), and also assess the effect of complexation processes on the protease activity and stability of the enzymes in question. Methods: The CTS–DMAEMA graft copolymer was obtained by solution radical polymerization in 2% acetic acid. Protein–polysaccharide complexes were received in glycine buffer. The protein content in the obtained complexes was determined by the modified Lowry method and proteolytic activity of enzymes as part of complexes was assessed using azocasein as a substrate. Molecular docking was used to identify the types of bonds and interactions within protein–polysaccharide complexes. Results and Discussion: Complexes of cysteine proteases (bromelain, papain, and ficin) with the graft copolymer of chitosan with poly(N,N-dimethylaminoethyl methacrylate) were synthesized. It was found that the complexes have a lower protease activity than the native enzymes, because as a result of complex formation, the active site of cysteine proteases is shielded from the substrate, which complicates the catalysis process. The complexes are more stable compared to the native enzymes and retain up to 26% of protease activity after 21 days of incubation at 37°C in Tris-HCl buffer (pH 7.5). Conclusions: It was found that the proteolytic activity of the complexes is lower compared to their native forms of enzymes. The results of molecular docking showed that the modified chitosan is located in the catalytic pocket of cysteine proteases globules. The synthesized complexes have increased stability on storage under physiological conditions, which makes them promising candidates for the development of wound healing drugs. [ABSTRACT FROM AUTHOR]

Separation of equally sized particles distinguished solely by interfacial properties remains a highly challenging task. Herein, a particle fractioning method is proposed, which is suitable to differentiate between polymer‐grafted microparticles that are equal in size. The separation relies on the combination of a pressure driven microfluidic flow, together with simultaneous light illumination and temperature control. Heating the solution forces thermo‐responsive surface grafts to undergo a volume phase transition and therefore locally changing the interfacial properties of the microparticles. Light illumination induces the phoretic/osmotic activity of the microparticles and lifts them into a higher plane, where hovering particles experience a different shear stress proportional to the height. The light‐induced hovering height depends on the interfacial properties, and this complex interaction leads to different movements of the microparticles as a function of their surface grafting. The concepts are visualized in experimental studies, where the complex physical principle provides a simple method for fractioning a binary mixture with at least one thermo‐responsive polymer graft. [ABSTRACT FROM AUTHOR]

[Display omitted] Composite solid electrolytes (CSEs) composed of polymer matrix and inorganic fillers show considerable potential for applications in all-solid-state lithium (Li) metal batteries. However, challenges such as fillers agglomeration and low lithium ion transference number (t Li+) remain significant obstacles to the practical application of CSEs. Herein, a general strategy of graft polymerization on the fillers surface to modulate the interface compatibility with the polymer matrix is proposed, and CSEs are prepared to verify the feasibility. The microstructure and composition of the surface coating of the fillers are analyzed, with subsequent studies of the fillers distribution within the CSEs confirming the improved interface compatibility. The enhancement of interface compatibility facilitates uniform dispersion of fillers, thereby greatly improving the utilization of fillers. CSEs exhibits high ionic conductivity (0.163 mS·cm−1 at 30 °C) and t Li+ (0.77), which gives the battery excellent rate performance and cycle stability. Therefore, chemical grafting of polymer onto the fillers surface to enhance the interface compatibility with the polymer matrix represents a promising strategy for the practical application of solid-state batteries. [ABSTRACT FROM AUTHOR]

Chitosan is a natural elicitor, used for stimulating plant growth and inducing plant defense. However, due to difficulty in monitoring root growth and activity, the effects of chitosan treatment on plant root systems have been less studied as compared to plant shoot parts that include leaves, seeds, and fruits. This results in an indefinite outcome of the benefits of chitosan on plant roots. Therefore, this review aims to evaluate the effects of chitosan treatment on root growth and defense responses based on current evidence. Interestingly, many studies have demonstrated that chitosan can induce plant root defense systems, yet conversely inhibiting root growth. The effects were most clearly observed from studies using liquid or solid media as substrates, while the results from the studies using soil were inconclusive and require additional investigation to observe the effects of environmental factors. In addition, root chitosan treatment showed variable effects on shoot growth, where low chitosan concentrations tend to promote shoot growth, but high chitosan concentrations may affect shoot development. Additionally, this review discusses the potential methods of chitosan application onto plant roots. Water insolubility of chitosan is likely a major issue for root treatment. Chitosan can be dissolved in acids, but this could induce acidity stress in plant roots. Modified versions of chitosan, such as chitosan nanoparticles, carboxylated chitosan, and graft chitosan copolymers have been developed to improve solubility and functionality. Chitosan nanoparticles can also be used to encapsulate other biocontrol agents to augment biological effects on plant defense. In conclusion, root chitosan treatment could help to promote plant defense and prevent root infections, abating the uses of chemical fungicides in agriculture. However, further research is required to monitor the impact of root chitosan treatment on long-term plant growth in order to gain multifaceted information to maximize the effectiveness of root chitosan application. [ABSTRACT FROM AUTHOR]

Liquid-like surfaces have demonstrated immense potential in their ability to resist cell adhesion, a critical requirement for numerous applications across various domains. However, the conventional methodologies for preparing liquid-like surfaces often entail a complex multi-step polymer brush modification process, which is not only time-consuming but also presents significant challenges. In this work, we developed a single-cycle polymer brush modification strategy to build liquid-like surfaces by leveraging high-molecular-weight bis(3-aminopropyl)-terminated polydimethylsiloxane, which significantly simplifies the preparation process. The resultant liquid-like surface is endowed with exceptional slipperiness, effectively inhibiting bacterial colonization and diminishing the adherence of platelets. Moreover, it offers promising implications for reducing the dependency on anticoagulants in microfluidic systems constructed from PDMS, all while sustaining its antithrombotic attributes. [ABSTRACT FROM AUTHOR]

Comb-like polymers have shown potential as advanced materials for a diverse palette of applications due to the tunability of their polymer architecture. To date, however, it still remains a challenge to understand how the conformational properties of these polymers arise from the interplay of their architectural parameters. In this work, extensive simulations were performed using dissipative particle dynamics to investigate the effect of grafting density, backbone length, and sidechain length on the conformations of comb-like polymers immersed in a good solvent. To quantify the effect of these architectural parameters on polymer conformations, we computed the asphericity, radius of gyration, and backbone and sidechain end-to-end distances. Bond–bond correlation functions and effective Kuhn lengths were computed to quantify the topological stiffness induced by sidechain–sidechain interactions. Simulation results reveal that the effective Kuhn length increases as grafting density and sidechain length increase, in agreement with previous experimental and theoretical studies. This increase in stiffness results in comb-like polymers adopting extended conformations as grafting density and sidechain length increase. Simulation results regarding the radius of gyration of comb-like polymers as a function of grafting density are compared with scaling theory predictions based on a free energy proposed by Morozova and Lodge [ACS Macro Lett. 6, 1274–1279 (2017)] and scaling arguments by Tang et al. [Macromolecules 55, 8668–8675 (2022)]. [ABSTRACT FROM AUTHOR]

A new highly effective sizing reagent based on grafted collagen copolymers has been proposed for cotton yarn. The copolymers were synthesized by reacting an aqueous solution of collagen with acrylic monomers--acrylic, matacrylic acids, and their amides in the presence of potassium persulfate. Based on Scanning electron microscopy--Energy dispersive (SEM-EDS) analysis data, the composition of the copolymers was determined. Unsaturated acids are more actively grafted onto collagen than their amides. When a polymer film is formed from a solution of a collagen copolymer with (meth)acrylic acid, microcracks appear on the surface of the sample; microcracks are absent in films of copolymers with (meth)acrylamide. Films of copolymers, especially methacrylamide, are quite flexible and contribute to a significant improvement in the properties of the yarn. The tensile strength of yarn sized with copolymers increases by 20%-65% compared to unsized yarn, and by 13%--38% compared to yarn sized with a starch solution. At the same time, the relative tensile elongation of the experimental yarn improves by 14%-58%, while this property of starch-size yarn deteriorates by 14%-22% compared to unsized yarn. The complete removal of graft copolymers from the surface of the yarn in the process of biochemical desizing using the enzyme protease is shown. Highlights * Graft copolymerization of (meth)aciylamide with collagen was carried out. * Grafting is initiated by the interaction of collagen with potassium persulfate. * The synthesized copolymers are effective sizing reagents for cotton yarn. * The copolymer with poly(meth)acrylamide forms a flexible and stable film. * The protease enzyme completely removes the size from the surface of the yarn. KEYWORDS acrylic monomer, collagen, cotton yam, graft copolymer, morphology, sizing, 1 | INTRODUCTION The preparation of cotton yarn for weaving is a technological link between the production of yarn and the production of fabric, therefore it plays a significant role [...]

We develop a theory for the motion of a particle grafted with inhomogeneous bead-spring Rouse chains via the generalized Langevin equation (GLE), where individual grafted polymers are allowed to take different bead friction coefficients, spring constants, and chain lengths. An exact solution of the memory kernel K(t) is obtained for the particle in the time (t) domain in the GLE, which depends only on the relaxation of the grafted chains. The t-dependent mean square displacement g(t) of the polymer-grafted particle is then derived as a function of the friction coefficient γ0 of the bare particle and K(t). Our theory offers a direct way to quantify the contributions of the grafted chain relaxation to the mobility of the particle in terms of K(t). This powerful feature enables us to clarify the effect on g(t) of dynamical coupling between the particle and grafted chains, leading to the identification of a relaxation time of fundamental importance in polymer-grafted particles, namely, the particle relaxation time. This timescale quantifies the competition between the contributions of the solvent and grafted chains to the friction of the grafted particle and separates g(t) into the particle- and chain-dominated regimes. The monomer relaxation time and the grafted chain relaxation time further divide the chain-dominated regime of g(t) into subdiffusive and diffusive regimes. Analysis of the asymptotic behaviors of K(t) and g(t) provides a clear physical picture of the mobility of the particle in different dynamical regimes, shedding light on the complex dynamics of polymer-grafted particles. [ABSTRACT FROM AUTHOR]

Carboxymethyl cellulose sodium salt is a common water-soluble derivative of cellulose. It serves as a bioinert mucoadhesive material extensively used in biomedicine, particularly for crafting targeted drug delivery systems. In our study, we demonstrate that graft copolymers of sodium carboxymethyl-cellulose with poly(N-vinylimidazole) can function as carriers for the antibacterial drug metronidazole. Non-covalent associations form between the components, excluding the involvement of the nitro groups of the drug in the interaction. These loaded copolymers exhibit the capability to release the drug under conditions mimicking the stomach environment for up to 48 h. This renders the obtained associations promising candidates for the development of a metronidazole-targeted delivery system.

Two oxidovanadium(IV) complexes [VO(xbp‐sc)] (1) and [VO(xbp‐tc)] (2) were prepared using hydrazine‐ether mixed functionality ligands Hxbp‐sc (I) and Hxbp‐tc (II), respectively. Complexes 1 and 2 were carefully grafted separately into imidazole‐modified chloromethylated polystyrene (Ps−Im) and unmodified chloromethylated polystyrene (PS−Cl) beads. Successfully anchored vanadium complexes Ps−Im‐[VO(xbp‐sc)] (3), Ps−Im‐[VO(xbp‐tc)] (4), Ps‐[VO(xbp‐sc)] (5), and Ps‐[VO(xbp‐tc)] (6) were tested for their catalytic potential towards the oxidation of aliphatic alcohols in the presence of hydrogen peroxide. Polymer‐grafted catalysts display excellent substrate conversion compared to most recent reports and good recyclability up to three cycles without losing much reactivity. High TOF values in the range of 183–591 h−1 are observed for the supported catalysts 3–6. The highest substrate conversion is observed for ethanol (63–97 %) under the optimized reaction conditions. Mainly, better substrate conversion is obtained with imidazole‐modified polymer beads grafted catalysts 3 and 4 than those grafted on unmodified polymer beads (5 and 6). Moreover, catalysts with the semicarbazide group in their ligand framework (3 and 5) show better reactivity towards alcohol with fewer carbon atoms. On the contrary, alcohols with longer carbon chains oxidize more easily in the presence of the catalyst with thiosemicarbazide frameworks (4 and 6). [ABSTRACT FROM AUTHOR]

Nanorods as building blocks are promising to construct functional superstructures. A paramagnetic Fe3O4‐based composite nanorod is large‐scale synthesized from the poly(2‐vinylpyridine) (P2VP) side chain grafted polymer bottlebrush by electrostatics‐mediated intramolecular crosslinking via metallic coordination. Ultrasonication‐assisted fracturing of the composite nanorod derives the corresponding A2‐type composite nanorods whose two ends are active with the metallic coordinated P2VP exposed. The active ends are prone to connection upon feeding ligands (acidic or alkaline) or metallic ions to trigger the organization of the A2‐type nanorods toward functional superstructures. Their microstructure is tunable from linear nanowires to branches, which is dependent on the valent state of the assistant chemicals. The report method is easily extended to derive a family of A2‐type active nanorods with varied compositions and functions which are capable to organize functional nanomaterials with tunable microstructure. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is a multifunctional material with a myriad of potential applications, from high-power electronics to friction applications to power generation. Grafting preceramic polymers (PCPs) from SiC nanoparticles would create a platform for forming SiC via a polymer derived route that would have advantages over simple particle-PCP slurries and may enable new additive manufacturing inks or spreadable coatings with controlled rheology. Grafting PCPs directly on SiC powders would greatly improve dispersion of these particles and yield a single component system. Moreover, PCP-grafted-SiC would be a new addition to the burgeoning field of polymer grafted nanoparticles (PGNPs). Herein, SiC nanoparticles were surface-modified in a grafting-from polymerization reaction to create polycarbosilane (PCS) grafted SiC. Surface grafting was verified through a number of analytical techniques and the synthesized materials were pyrolyzed at 1600 °C. The PCS-grafted SiC retained 66 % of its pre-pyrolysis mass, representing a significant improvement over PCS-grafted silica nanoparticles from our previous work (20 wt% yield). In addition to an increased ceramic yield, the grafting of PCS to SiC also resulted in the formation of a SiC phase not present in the simple physical mixture of SiC nanopowder in PCS. This study demonstrated that PCP-grafted nanoparticles (GNPs) can be synthesized utilizing non-oxide nanoparticle cores with desirable rheology, opening possibilities for future ceramic inks and coatings. [ABSTRACT FROM AUTHOR]

In this work, using the combination of atom transfer radical polymerization and click chemistry, the graft copolymer polysulfone‐graft‐poly (methyl methacrylate) (PSf‐g‐PMMA) was synthesized as a modifying agent. The copolymer was embedded in the PSf substrate using a nonsolvent phase inversion method. Then, the modified substrate was used to make thin film composite forward osmosis (TFC‐FO) membranes using the interfacial polymerization method. Also, the effect of PSf‐g‐PMMA copolymer content on the surface properties of the membrane, as well as the filtration performance, was investigated. The increase in hydrophilicity, porosity, and average pore diameter indicated the favorable effect of PSf‐g‐PMMA copolymer on the characteristics of modified substrates. In addition, the improvement in the membrane morphology (an increase in the length and number of finger‐like pores) provided a substrate with low tortuosity and structure parameters. Therefore, the pure water permeability increased from 79.9 LMH/bar for the control membrane to 372.1 LMH/bar for the membrane containing 20 wt.% of PSf‐g‐PMMA copolymer. Investigating the FO separation properties of TFC‐FO membranes showed an increase in water flux and selectivity due to an improvement in the morphology of the modified substrate with low structural parameters. The new TFC‐FO membranes have been optimized, and water flux has significantly improved. Compared with the control membrane, which did not have copolymer blending, the new membranes have a triply enhanced water flux of 17.1 LMH. In addition, the selectivity of these optimized membranes has improved when 1 M NaCl is used as the draw, and DI water is used as the feed in the FO mode. [ABSTRACT FROM AUTHOR]

Carboxymethyl cellulose sodium salt is a common water-soluble derivative of cellulose. It serves as a bioinert mucoadhesive material extensively used in biomedicine, particularly for crafting targeted drug delivery systems. In our study, we demonstrate that graft copolymers of sodium carboxymethyl-cellulose with poly(N-vinylimidazole) can function as carriers for the antibacterial drug metronidazole. Non-covalent associations form between the components, excluding the involvement of the nitro groups of the drug in the interaction. These loaded copolymers exhibit the capability to release the drug under conditions mimicking the stomach environment for up to 48 h. This renders the obtained associations promising candidates for the development of a metronidazole-targeted delivery system. [ABSTRACT FROM AUTHOR]

In this paper, epoxy-functionalized AES resins (GAES resins) were prepared by high-temperature solution polymerization, and FTIR spectrograms demonstrated the successful grafting of styrene (St), acrylonitrile (AN), and glycidyl methacrylate (GMA) onto ethylene/propylene/diene mischpolymer (EPDM) rubbers. The influences of reaction conditions, i.e. the content of initiator and chain transfer agent, EPDM and GMA on the grafting ratio, composition of free copolymers, molecular weights and polymer dispersity index (PDI) of GAES resins were detaily investigated. The influence of GMA content on the thermal stabilities of GAES resins was also discussed. Experimental results showed that under the optimized experimental conditions, the highest grafting ratio of GAES resins reached to 39.2% and the grafting efficiency was 35.3%. Under the same reaction conditions, the molecular weights of free copolymers reached to 70,000 g mol−1. The initiator had no obvious influence on the composition of free copolymers, but the component of GMA in free copolymers increased gradually with increasing content of EPDM. Thermogravimetry (TG) analysis results indicated that the incorporation of GMA decreased the thermal stabilities of GAES resins. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies are attractive therapeutic agents in a wide range of human disorders that bind specifically to their target through their complementary‐determining regions (CDRs). Small proteins with structurally preserved CDRs are promising antibodies mimetics. In this in silico study, we presented new antibody mimetics against the cancer marker epidermal growth factor receptor (EGFR) created by the CDRs grafting technique. Ten potential graft acceptor sites that efficiently immobilize the grafted CDR loops were selected from three small protein scaffolds using a computer. The three most involved CDR loops in antibody‐receptor interactions extracted from panitumumab antibody against the EGFR domain III crystal structure were then grafted to the selected scaffolds through the loop randomization technique. The combination of three CDR loops and 10 grafting sites revealed that three of the 36 combinations showed specific binding to EGFR DIII by binding energy calculations. Thus, the present strategy and selected small protein scaffolds are promising tools in the design of new binders against EGFR with high binding energy. [ABSTRACT FROM AUTHOR]

Graphene-based adsorbents show great potential for application in the field of environmental pollution treatment due to their unique two-dimensional structure, high specific surface area, and tunable surface chemistry. This paper reviews the research on the application of graphene and its derivatives as novel adsorbents in the field of wastewater treatment in recent years, focusing on the preparation and functionalization of graphene-based adsorbents, as well as their adsorption performance and mechanism of action in the removal of inorganic and organic pollutants, and provides an outlook on the future directions of the research on graphene-based adsorbents. The analysis in this paper focuses on the functionalization of graphene-based adsorbents by introducing magnetic particles, hybridization with other materials, and grafting with polymers. The modified graphene-based adsorbents showed significant adsorption and removal of pollutants and were easy to recycle and regenerate. The adsorption of pollutants on graphene-based adsorbents is mainly carried out through π–π interaction, hydrogen bonding, and electrostatic interaction, which is related to the structure of the pollutants. Future research directions on graphene-based adsorbents should focus on in-depth adsorption mechanism studies and the development of cost-effective graphene-based adsorbents for wastewater treatment. [ABSTRACT FROM AUTHOR]

Proteoglycans (PGs), which have glycosaminoglycan chains attached to their protein cores, are essential for maintaining the morphology and function of healthy body tissues. Extracellular PGs perform various functions, classified into the following four categories: i) the modulation of tissue mechanical properties; ii) the regulation and protection of the extracellular matrix; iii) protein sequestration; and iv) the regulation of cell signaling. The depletion of PGs may significantly impair tissue function, encompassing compromised mechanical characteristics and unregulated inflammatory responses. Since PGs play critical roles in the function of healthy tissues and their synthesis is complex, the development of PG mimetic molecules that recapitulate PG functions for tissue engineering and therapeutic applications has attracted the interest of researchers for more than 20 years. These approaches have ranged from semisynthetic graft copolymers to recombinant PG domains produced by cells that have undergone genetic modifications. This review discusses some essential extracellular PG functions and approaches to mimicking these functions. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes various articles on topics such as latent fingerprint detection, MXene materials in electrochemical energy storage systems, sustainable production of metal-organic frameworks, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a brief overview of the articles included in the journal issue, allowing library patrons to quickly identify relevant research topics. [Extracted from the article]

Controlling the extensional rheological properties of solutions is of great interest for a number of applications, such as printing and coatings, as polymeric additives can modify a fluid's droplet size, formation, and breakup. We have measured the extensional flows of polyacrylamide graft poly(ethylene glycol) amine (PAM‐g‐PEGa) solutions as a function of grafting density. PAM‐g‐PEGa is synthesized with grafting densities of 2.5%, 5.5%, 8%, and 30% and extensional flow was analyzed with drop‐on‐substrate rheology. Flow time scales and profiles are then compared to understand the effects of backbone extension from the addition of side chains. At low grafting densities, the viscous friction from the added side chains is comparable to, and in some cases, counteracts the losses in extensibility to the graft polymer's backbone, leading to increases in the relaxation time of the polymer. At higher grafting densities, the extension of the backbone reduces the relaxation time. By characterizing the effects of the graft density architecture on extensional flows, we are able to fine‐tune and control the breakup dynamics of elastic solutions. [ABSTRACT FROM AUTHOR]

The present work focuses on comparing the performance of novel cationic graft copolymer polyvinylpyrrolidone-graft-poly(acrylamide-co-diallyldimethylammonium chloride) (PVP-g-p(AM-co-DADMAC)) synthesized via microwave-assisted technique, with varying amounts of monomers acrylamide (AM) and diallyldimethylammonium chloride (DADMAC) as a flocculant for sugarcane juice. The intended grafting was supported by extensive characterization of the material by various physicochemical methods. As compared to only AM or DADMAC grafted onto PVP, grafted copolymer with highest DADMAC-to-AM ratio was found to be more effective in removing colloids from fresh unaltered cane juice. The mode of action of the synthesized flocculant was explained by synergistic bridging and charge neutralization mechanism. The best grade of PVP-g-p(AM-co-DADMAC) at an optimum dose of only four ppm (within US FDA approved limit) showed a good reduction in the zeta potential (− 7.8 to − 2.9 mV) of the juice along with the formation of large-size floc (618 nm) without affecting the percentage of natural sugar content (degree brix- °bx). [ABSTRACT FROM AUTHOR]

With the rapid development of the maritime industry, oily wastewater discharges and oil spills cause acute environmental challenges. Currently, cellulosic materials with switchable wettability have received increasing interest for oil–water separation. Moreover, work efficiency needs to be improved with a shorter response time. To realize these, dimethylaminoethyl methacrylate (DMAEMA) and methyltrimethoxysilane (MTMS) synthesized pH‐responsive copolymer (DMAEMA‐co‐MTMS) which grafted banana nanocellulose fiber made from wasted pseudostem to achieve the pH‐responsive aerogel (BCNA‐DcoM). BCNA‐DcoM exhibited hydrophilic/submerged lipophobicity under acidic conditions and hydrophobic/lipophilic under alkaline conditions. A response time of 3 s and a contact angle of 135° were shown when the mass ratio of banana nanocellulose suspension, MTMS, and DMAEMA‐co‐MTMS was 5:3:9. Moreover, BCNA‐DcoM possessed favorable mechanical friction properties, salt resistance (25% NaCl), compression resilience (50 cycles of compression at 60% strain), switchable wettability (>30 cycles), and highly efficient separation performance (>96%). The adsorption capacity of BCNA‐DcoM for oil is 80–184 times the initial weight of the aerogel based on the different oil densities. For practical applications, BCNA‐DcoM could continuously separate oil–water mixtures with the constant‐flow pump. The present work provides more possibilities for rapidly treating industrial oily wastewater with low‐cost and ecological banana pseudostem materials. [ABSTRACT FROM AUTHOR]

Ferroelectric polymers have emerged as crucial materials for the development of advanced organic electronic devices. Their recent high‐end commercial applications as fingerprint sensors have only increased the amount of scientific interest around them. Despite an ever‐larger body of studies focusing on optimizing the properties of ferroelectric polymers by physical means (e. g. annealing, stretching, blending or nano‐structuring), post‐polymerization chemical modification of such polymers has only recently become a field of active study with great promise in expanding the scope of those polymers. In this work, a solution‐based post‐polymerization modification method was developed for the safe and facile grafting of a plethora of functional groups to the backbone of commercially available Poly(vinylidene fluoride‐co‐trifluoroethylene P(VDF‐co‐TrFE) ferroelectric polymers. To showcase the versatility of this approach, photosensitive groups were grafted onto the polymeric backbone, enabling them to undergo photo‐cross‐linking. Finally, these modified polymers were used as functional negative photoresists in a photolithographic process, highlighting the potential of this method to integrate ferroelectric fluorinated electroactive polymers into standard electronic microfabrication production lines. [ABSTRACT FROM AUTHOR]

Humic acids (HAs) are widely used as filtrate and viscosity reducers in drilling fluids. However, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. High-temperature coal pitch (CP) is a by-product from coal pyrolysis above 650 °C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP (CP-HA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer (Graft CP-HA-K polymer) is synthesized with CP-HA-K, hydrolyzed polyacrylonitrile sodium salt (Na-HPAN), urea, formaldehyde, phenol and acrylamide (AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-HA-K are 1 wt% catalyst dosage, 30 wt% KOH dosage, a reaction temperature of 250 °C, and a reaction time of 2 h, resulting in a maximum yield of CP-HA-K of 39.58%. The temperature resistance of the Graft CP-HA-K polymer is measured to be 177.39 °C, which is 55.39 °C higher than that of commercial HA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-HA-K polymer, which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120°C for a specified duration, the Graft CP-HA-K polymer demonstrates significantly higher viscosity reduction (42.12%) compared to commercial HA-K (C-HA-K). Furthermore, the Graft CP-HA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-HA-K polymer. The action mechanism of Graft CP-HA-K polymer on high-temperature drilling fluid is that the Graft CP-HA-K polymer can increase the repulsive force between solid particles and disrupt bentonite's reticulation structure. Overall, this research provides novelty insights into the synthesis of artificial humic acid materials and the development of temperature-resistant viscosity reducers, offering a new avenue for the utilization of CP resources. [ABSTRACT FROM AUTHOR]

In this study, poly(ɛ-caprolactone-g-2-hydroxy ethyl methacrylate) [P(CL-g-HEMA)] graft copolymer hydrogels were successfully synthesized through multi-step reactions. For this purpose, firstly, hydroxyl-terminated poly(ɛ-caprolactone) (PCL-OH) was obtained by ring-opening polymerization (ROP) method of ɛ-caprolactone using 3-chlor-1,2-propanediol initiator, which is suitable for ring-opening polymerization method. Then, from the reaction of synthesized PCL-OH and 3-bromopropionyl chloride, a new brominated poly(ɛ-caprolactone) (PCL-Br) was synthesized for use as a functionalized atom transfer radical polymerization (ATRP) initiator. Poly(ɛ-caprolactone-g-2-hydroxy ethyl methacrylate) [P(CL-g-HEMA)] graft copolymer hydrogels were synthesized by "grafting from" atom transfer radical polymerization (ATRP) of 2-hydroxy ethyl methacrylate (HEMA) presence the new synthesized functionalized ATRP initiator (PCL-Br) and hydrogel properties were investigated. The synthesized functionalized initiators and graft copolymer hydrogel were characterized by spectroscopic methods such as 1H-NMR, FT-IR, TGA, DSC and SEM. The observation of two different decomposition temperatures, respectively, from the TGA analysis results may support the formation of the biblock graft copolymer. A glass transition temperature (Tg) of the graft copolymer hydrogel was found by DSC, and this value is between the Tg values of the homopolymers forming the graft copolymer hydrogel. Water swelling values of graft copolymer hydrogels were measured and calculated every 24 h in pure water with pH = 7 at from + 4 to 65 °C. Considering the weight of dry graft copolymer hydrogels, it was seen that water was absorbed at most at + 4 °C. As the temperature increased, the water absorption or swelling of the hydrogel decreased. [ABSTRACT FROM AUTHOR]

The functionalization of polymeric matrices through graft polymerization offers various advantages by providing new properties, allowing for additional chemical reactions that the matrix alone could not undergo or that would require drastic chemical conditions to occur. In this work, epoxy groups were incorporated through a graft polymer of poly(glycidyl methacrylate), using a prefunctionalization with peroxide groups in the polytetrafluoroethylene matrix through gamma radiation. These peroxide groups were subsequently used as radical chemical initiators in the graft polymerization reaction of glycidyl methacrylate. The graft polymerization reaction was studied based on the absorbed dose, monomer concentration, reaction time, and temperature. [ABSTRACT FROM AUTHOR]

The objective of the present study was to optimize the microwave-assisted synthesis of the acrylamide graft copolymer of Acacia nilotica gum (AM-co-ANG). Furthermore, graft copolymer was used for the formulation of a nanoparticulate system using a novel top to bottom solvent antisolvent technique for the delivery of melatonin. Grafting of ANG was optimized by using 32 factorial design, where concentrations of polymer and monomer (acrylamide) were used as independent variables and swelling index in acidic (0.1 N HCl) and basic (1 N NaOH) pH. Grafted polymers were further used to develop and optimize nanoparticulate system using concentration of the graft copolymer and concentration of drug as independent variables. The size of the nanoformulation and entrapment efficiency were selected as dependent variables. Difference in infrared spectrum and absorbance maxima in the ultraviolet region confirm that grafting has taken place. Porous structure and a higher contact angle confirmed hydrophobic nature of AM-co-ANG as compared with the native polymer. Acrylamide graft copolymers show more swelling in 1 N NaOH as compared with 0.1 N HCl. In vitro toxicity studies in hepatic (HepG2 cell line), brain (SHSY5Y cell line), and skin (HaCaT cell line) cells easily predict that synthesized polymer have no cytotoxicity. The entrapment efficiency ranged from 55.24 ± 1.35% to 73.21 ± 1.83%. A nonlinear correlation was observed between independent and dependent variables, as confirmed by multivariate analysis of variance, surface regression, and the correlation report. The prepared formulations were able to release drug up to 12 h. The regression coefficient easily predicted that most of the formulations followed Baker–Lonsdale drug release kinetics. [ABSTRACT FROM AUTHOR]

Given the environmental concerns surrounding fluoromaterials, the use of high‐cost perfluorinated sulfonic acids (PFSAs) in fuel cells and water electrolysis contradicts the pursuit of clean energy systems. Herein, we present a fluorine‐free dumbbell‐shaped block‐graft copolymer, derived from the cost‐effective triblock copolymer, poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) (SEBS), for polymer electrolyte membranes (PEMs). This unique polymer shape led to the alignment of the hydrophobic‐hydrophilic domains along a preferred orientation, resulting in the construction of interconnected proton channels across the membrane. A bicontinuous network allowed efficient proton transport with reduced tortuosity, leading to an exceptional ionic conductivity (249 mS cm−1 at 80 °C and 90 % relative humidity (RH)), despite a low ion exchange capacity (IEC; 1.41). Furthermore, membrane electrode assembly (MEA) prepared with our membrane exhibited stable performance over a period of 150 h at 80 °C and 30 % RH. This study demonstrates a novel polymer structure design and highlights a promising outlook for hydrocarbon PEMs as alternatives to PFSAs. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are the best candidates for high‐energy density system. However, the unstable solid electrolyte interphase (SEI) caused by notorious lithium dendrite growth and huge volume fluctuation under practical conditions hinders its commercialization. Here, a functional copolymer composed of monomer is designed with ordered −CF2− groups grafted to viscoelastic backbone to provide homogeneous and self‐adapting in situ LiF‐rich interface. Hence, the robust interface facilitates rapid Li+ flux and suppresses dendritic Li growth. Furthermore, an elastic composite lithium metal anode (FELMA) based on the designed functional copolymer is fabricated through a cost‐effective approach. The FELMA shows excellent cycle stability with ultra‐low volume expansion rate of 0.16% per cycle after 200 cycles at the condition of 3 mA cm−2–3 mAh cm−2. The full batteries assembled with high‐loading LiNi0.8Co0.1Mn0.1O2 (NCM811, 4.1 mAh cm−2) cathode can maintain 80% capacity retention after 320 cycles under N/P = 2.17 and E/C = 2.68 g Ah−1, with the cycling life increased by 220% than Li||NCM811. A prototype 418 Wh kg−1 pouch cell (5.16 Ah) with N/P ratio of 0.88 and E/C ratio of 2.39 g Ah−1 shows stable cycling. [ABSTRACT FROM AUTHOR]

Structurally defined, protein‐grafted nanoparticles are widely used in various biomedical applications, particularly as intelligent nanocarriers for drug delivery. The integration of synthetic polymers with natural proteins such as silk sericin enhances the functionality and stability of these nanocarriers, making them suitable for targeted and controlled drug release. In this context, an optimized grafting procedure for silk sericin is presented, employing a protein macroinitiator and atom transfer radical polymerization (ATRP). This study aims to elucidate the significance of the grafting process in tailoring the structure of sericin through the chemistry of synthetic grafts. The grafting procedure uses block copolymers of N‐isopropylacrylamide (NIPAM) and 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS), such as Poly‐(AMPS‐block‐NIPAM)/Poly‐(NIPAM‐block‐AMPS). The procedure employs both one‐step and two‐step synthesis methods to produce a well‐defined, biofunctionalized sericin. Subsequently, sericin‐based nanoparticles are prepared, demonstrating the significance of the optimized procedure. The synthesized products undergo structural analysis using H‐NMR, FTIR‐ATR, XPS, DLS, and zeta potential measurements. In addition, their thermal behavior is assessed using differential scanning calorimetry. To further investigate the prepared nanoparticles, SEM and DLS analyses are conducted. Through synthesis optimization, position and length of each synthetic block is precisely determined, significantly influencing properties of the grafted products and characteristics of the resulting nanoparticles. [ABSTRACT FROM AUTHOR]

Herein, conductive and stable partially fluorinated multi-cationic alkaline membrane (AM) has been reported by macromolecular modification of poly (vinylidene fluoride) (PVDF) and chemical grafting of vinyl benzyl chloride (VBC). Quaternization was achieved using different amines, to control the concentration of quaternary ammonium (QA) groups. Different multi-cationic AMs were analysed by their structural (1H NMR and FT-IR) and morphological properties, ion-exchange capacity (IEC), water uptake (WU), alkaline conductivity (κ m ), and stabilities (mechanical, chemical, and thermal). Due to presence of multi cationic groups and thus steric hindrance, reported membranes were robust in alkaline medium. Single-cell anion exchange membrane fuel cell (AMFC) assembled with Tri-amino-VBC-g-PVDF membrane, exhibited relatively high performance (open circuit voltage (OCV): 1.03 V, peak power density: 244.0 mW cm−2 at 400.0 mA cm−2), in compare with other AMs reported in the literature. It was observed that AMFC performance was strongly depends on cationic group density, and present study explored the utilization possibility of partially fluorinated polymer matrix with multi-cationic groups for long lifetime during AMFC application. [Display omitted] • High performance partially fluorinated multi-cationic alkaline membrane. • Alkaline membrane robust for Hofmann β -elimination and SN 2 reactions. • 96.34% remained conductivity after alkali treatment at 80 °C for 768 h. • 244.0 mW cm−2 maximum power density at 400.0 mA cm−2. [ABSTRACT FROM AUTHOR]