Graft Polymerization Research Articles

Quaternization-based graft modification of straw fibers for conditioning the sludge dewatering performance.

Extracellular polymeric substances (EPS) are a critical influencing factor in sludge dewatering. Disrupting such EPS contributes to the release of bound water in sludge, enhancing the sludge dewatering performance. In This study, quaternized straw fibers that are destructive to the EPS structure and components in active sludge were prepared useing heterogeneous free radical graft polymerization. Straw fibers, dimethyl diallyl ammonium chloride (DMDAAC), ammonium persulfate (APS), and acrylamide (AM) were taken as the substrate, grafting monomer, catalyst, and cross-linking agent, respectively.The optimal processing conditions determined for the DMDAAC-based quaternization and graft modification of straw fibers were as follows: reaction temperature of 60 °C, reaction time of 5 h, 0.100 g of catalyst APS dosage per gram of straw, and 3.000 ml of DMDAAC dosage per gram of straw. The optimal processing conditions yielded 1.335 g of modified straw fibers per gram of straw, 33.67% grafting rate, and 31.70% substitution of the quaternary ammonium groups. The capillary suction time (CST) was conditioned from 243.3 ± 22.6 s in the original sludge to 134.5 ± 34.45 s. The specific resistance to filtration (SRF) was reduced from 8.82 ± 0.51 × 1012 m/kg in the original sludge to 4.59 ± 0.23 × 1012 m/kg.

Amidoxime-based radio-microspheres for Internal Irradiation combined with a checkpoint-blocking nanobody boost antitumor immunity

Trans-arterial radioembolization (TARE) therapy confronts significant technical challenges in the preparation of metal nuclide-labeled microsphere carriers, the development of stable and efficient radionuclide labeling strategies, and the ability to treat multiple small lesions in solid tumors. In this study, we synthesized 177Lu-labeled amidoxime-based polyvinyl alcohol microspheres (177Lu-PVA-g-PAO-Ms) using in situ synthesis of trunk compounds with chem-induced grafting polymerization. The resulting 177Lu-PVA-g-PAO-Ms showed excellent stability in radiolabeling and demonstrated high accumulation and prolonged retention in various preclinical rodent models, as observed through SPECT/CT imaging. The cumulative radioactivity uptake in the tumor reached as high as 12.27 %ID/g. In a mouse subcutaneous metastatic tumor model, we observed a significant abscopal effect of radioimmunotherapy after administering a combination of 177Lu-PVA-g-PAO-Ms and an anti-PD-L1 nanobody. These findings highlight the ability of PVA-g-PAO-Ms to chelate radionuclides efficiently and securely. Furthermore, when combined with nanobodies with enhanced tissue penetration capabilities, these microspheres hold great potential as innovative carrier platforms, offering new therapeutic strategies for integrating TARE with systemic immunotherapy.

Fabrication of Hydrophobic PET Track-Etched Membranes using 2,2,3,3,4,4,4-Heptafluorobutyl Methacrylate for Water Desalination by Membrane Distillation

The world is currently facing a drinking water problem. Human activity, climate change and pollution of existing water bodies are exacerbating the problem. The scientists around the world are currently trying to purify water using effective and inexpensive methods. One such method is membrane distillation. Membrane distillation is a versatile thermally driven membrane separation process. This method of water purification has the potential to remove salts and other non-volatile components. The work is concerned with the desalination of salt solutions by membrane distillation using ion-track membranes based on polyethylene terephthalate (PET). PET ion-track membranes (PET TMs) were modified by photoinitiated graft polymerization of 2,2,3,3,4,4,4-heptafluorobutyl methacrylate (HFBMA) to make them hydrophobic. Optimal polymerization conditions (monomer concentration, reaction time) were determined, which led to an increase of water CA from 51 to 105°. The obtained membranes were used to purify the solution from NaCl. The effect of salt concentration as well as membrane properties on performance and degree of purification was studied. The results show that large pore size PET TMs modified with HFBMA has the potential to desalinate water in an efficient manner.

Surface Modification of Polyethylene Terephthalate Track-Etched Membranes by 2,2,3,3,4,4,5,5,6,6,7,7-Dodecafluoroheptyl Acrylate for Application in Water Desalination by Direct Contact Membrane Distillation.

In this work, the surfaces of poly (ethylene terephthalate) track-etched membranes (PET TeMs) with pore sizes of 670-1310 nm were hydrophobized with 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl acrylate (DFHA) by photoinitiated graft polymerization. Attenuated total reflection FTIR spectroscopy (ATR-FTIR), scanning electron microscopy (SEM) coupled to an energy-dispersive X-ray spectrometer (EDX), and contact angle measurements were used to identify and characterize the TeMs. The optimal parameters for graft polymerization were determined as follows: polymerization time of 60 min, monomer concentration of 30%, and distance from the UV source of 7 cm. The water contact angle of the modified membranes reached 97°, which is 51° for pristine membranes. The modified membranes were tested for water desalination using direct contact membrane distillation (DCMD) method. The effects of membrane pore size, the degree of grafting, and salt concentration on the performance of membrane distillation process were investigated. According to the results obtained, it has been concluded that large pore size hydrophobic TeMs modified by using DFHA could be used for desalinating water.

On the dual crosslinking for functionality enhancement of poly (acrylamide-co-acrylic acid)/chitosan-aluminum (III) ions and its characterization and sensory hydrogel fibers

In this report, we present a dual crosslinking hydrogel fiber made from polyamine saccharides chitosan (CS), synthesized through UV polymerization. This process utilizes Irgacure 2959 and N,N′-Methylenebisacrylamide (MBAA) as initiators, followed by immersion in an aluminum chloride (AlCl3) solution. The resulting hydrogel incorporates a dual crosslinking mechanism, quantitatively studied via Nuclear Magnetic Resonance (NMR) spectroscopy. This mechanism involves chemical crosslinking through radical graft polymerization of acrylamide and acrylic acid onto CS in the presence of MBAA, and physical crosslinking through hydrogen bonding interactions between P(AAm-co-AA) and a metal coordination bond. The mechanical properties of the hydrogel fiber enable it to withstand stresses up to 656 kPa and strains exceeding 300 %. Additionally, the hydrogel fiber exhibits conductivity at 1.96 Scm−1. Serving as a multifunctional material, it acts as a strain sensor and finds utility in optics. Remarkably, it demonstrates the capability to detect human motions such as finger bending and minor deformations like vibrations of the vocal cords. Furthermore, its ability to guide dynamic light makes it promising for optical applications. Consequently, this multifunctional hydrogel fiber emerges as a highly promising candidate for diverse applications in fields such as bioengineering and electronics.

Adhesive and healable supramolecular comb-polymers

A series of supramolecular comb polymers (SCPs) with adhesive and healable characteristics have been generated through the copolymerisation of methacrylate monomers featuring aromatic amide functionalities with lauryl methacrylate. By varying the amide functionality and loading of the supramolecular monomers, the properties of the resulting SCPs can be tailored, ultimately providing stable films at room temperature. As the loading of the amide-bearing monomer was increased, the phase separation between the hard and soft domains was enhanced, promoting larger hard-domain aggregation, as observed via atomic force microscopy (AFM). The mechanical properties of the SCPs correlated to the loading of the amide-bearing monomers, by increasing the mol% incorporation the resulting SCPs transition from possessing high strain to high ultimate tensile strength (UTS) and Young's modulus (YM). Over several re-adhesion cycles, the SCPs were shown to retain their shear strength when thermally adhered to both glass and aluminium substrates. Additionally, the SCPs exhibited healable properties at elevated temperatures (> 45 °C) allowing for the recovery of mechanical properties post-damage.

Designing pH-Responsive alizarin hybrids with easily tunable physicochemical properties via polymer grafting

This study focuses on the synthesis and characterization of novel pH-sensitive color materials based on alizarin, (1,2-dihydroxyanthraquinone), a natural pigment with versatile properties. The polymer-based indicators were prepared by grafting poly(methyl methacrylate) (PMMA) and poly(2-hydroxyethyl methacrylate) (PHEMA) from alizarin through an ester pH-liable bond, allowing for easy tunability of their physicochemical properties. The synthesis process involved the esterification of alizarin using 2-bromo-2-methylpropionyl bromide, facilitated by triethylamine as an acid scavenger. The resulting alizarin served as a difunctional initiator for atom transfer radical polymerization (ATRP) of methyl methacrylate and 2-hydroxyethyl methacrylate. The molecular structures of the synthesized hybrids were confirmed using 1H NMR and GPC analyses. The color characteristic, surface energy, thermal stability, and pH sensing activity of the alizarin-based hybrids were studied according to the type of grafted polymer nature as well as their degree of polymerization. PHEMA-grafted alizarin showed more rapid and more visible color changes under the influence of NH3 vapours compared to PMMA hybrids, due to their less hydrophobic nature. Furthermore, kinetic plots demonstrated various hydrolysis rates, with PMMA hydrolysis being slower than that of PHEMA due to its stronger hydrophobic character. UV–Vis spectra and GPC traces confirmed the occurrence of hydrolysis and successful cleavage of the ester bond links between the grafted polymers and alizarin with a decrease of the molar mass by a factor of two as expected. Such behavior offers opportunities for tailoring degradation profiles and achieving specific release profiles upon application of a wide range of polymers with varied character. The designed polymer-based pigments exhibited a high ability to monitor calorimetrically the pH changes, especially in alkaline conditions. Overall, this study contributes to the broadening of the application of alizarin-based materials, paving the way for further exploration and development in the field of functional materials.

Zwitterionic sulfobetaine methacrylate (SBMA) coating on hydrophobic acrylic intraocular lens material to prevent the adhesion of lens epithelial cells: Effect of SBMA concentration

Posterior capsular opacification (PCO), known as a prevalent complication of cataract surgery, occurs because of the attachment and abnormal proliferation of remaining lens epithelial cells (LECs) after cataract surgery. To reduce the PCO occurrence by improving cell adhesion resistance, we attempted zwitterionic sulfobetaine methacrylate (SBMA) coating through ultraviolet-induced graft polymerization on the surfaces of intraocular lens (IOL) materials. In this study, the effect of the concentration of SBMA monomers in the coating solutions adjusted from 10 wt% to 30 wt% was investigated on the chemical composition, morphology, and hydrophilicity of the IOL material surfaces modified with SBMA. Additionally, the effect of SBMA concentration on preventing adhesion to protein and LECs on the surfaces of SBMA-modified IOL materials was evaluated in vitro. Grafting of zwitterionic SBMA on the surfaces of hydrophobic acrylic IOL materials was confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and water contact angle (WCA). To evaluate the long-term hydrophilicity of coating films prepared with different concentrations of SBMA on the IOL material surfaces, the WCA of IOL materials stored in phosphate-buffered saline solution was measured as a function of time. The coating film prepared at a concentration of 20 wt% of SBMA showed the lowest WCA after 28 days, showing the best long-term hydrophilicity. Also, that prepared at a concentration of 20 wt% of SBMA exhibited the highest anti-adhesion effect on proteins and LECs.

Design and characterization of phosphonic acid-functionalized grafted sepiolite nanohybrids and their adsorption studies for removal of copper ions from aqueous solution.

In this study, we synthesized novel, economically efficient phosphonic acid-functionalized grafted sepiolite nanohybrids for selective elimination of copper ions from water. These nanohybrids were prepared by graft polymerization of glycidyl methacrylate onto sepiolite. We utilized free radical graft polymerization to graft glycidyl methacrylate (GMA) onto silanized sepiolite. The nanohybrids obtained exhibited a grafting percentage of 479% at 0.3 g of KPS initiator, 15% GMA monomer, and after 4 h of reaction. In pursuit of selectively removing metal ions from water, the nanohybrid with the highest grafting (PGE3) was chemically treated with phosphoric acid to introduce phosphonic acid groups on it. FTIR, XRD, SEM, CHO analysis, BET, and TGA analysis were utilized to characterize the developed nanohybrids. Batch adsorption studies were carried out using AAS process, examining the impact of pH, adsorbent weight, contact time, adsorbate concentration, and temperature on the adsorption process. Due to the selectivity of phosphonic acid groups towards copper ions, phosphonic acid-functionalized grafted sepiolite nanohybrid (PGE3-P) was used for copper ions removal from its aqueous solution. The maximum adsorption capacity of PGE3-P adsorbents was 134.5 mg/g for copper ions. The data from kinetic studies suggests that the adsorption process of copper ions followed a pseudosecond-order model. Furthermore, Langmuir isotherm proved to be a more fitting model in equilibrium isothermal investigations. The thermodynamic analysis of the data indicates that the adsorption of copper ions by PGE3-P is an endothermic and spontaneous process. The development of this phosphonic acid-functionalized grafted sepiolite nanohybrid adsorbent is a new contribution into the field of adsorption. The developed material can be utilized as selective adsorbent for elimination of other heavy metals from water.

Synthesis of Gd-DTPA Carborane-Containing Compound and Its Immobilization on Iron Oxide Nanoparticles for Potential Application in Neutron Capture Therapy.

Cancer is one of the leading causes of global mortality, and its incidence is increasing annually. Neutron capture therapy (NCT) is a unique anticancer modality capable of selectively eliminating tumor cells within normal tissues. The development of accelerator-based, clinically mountable neutron sources has stimulated a worldwide search for new, more effective compounds for NCT. We synthesized magnetic iron oxide nanoparticles (NPs) that concurrently incorporate boron and gadolinium, potentially enhancing the effectiveness of NCT. These magnetic nanoparticles underwent sequential modifications through silane polycondensation and allylamine graft polymerization, enabling the creation of functional amino groups on their surface. Characterization was performed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and transmission electron microscopy (TEM). ICP-AES measurements indicated that boron (B) content in the NPs reached 3.56 ppm/mg, while gadolinium (Gd) averaged 0.26 ppm/mg. Gadolinium desorption was observed within 4 h, with a peak rate of 61.74%. The biocompatibility of the NPs was confirmed through their relatively low cytotoxicity and sufficient cellular tolerability. Using NPs at non-toxic concentrations, we obtained B accumulation of up to 5.724 × 1010 atoms per cell, sufficient for successful NCT. Although limited by its content in the NP composition, the Gd amount may also contribute to NCT along with its diagnostic properties. Further development of the NPs is ongoing, focusing on increasing the boron and gadolinium content and creating active tumor targeting.

Elucidation of Dithiol-yne Comb Polymer Architectures by Tandem Mass Spectrometry and Ion Mobility Techniques.

Polymers have a wide range of applications depending on their composition, size, and architecture. Varying any of these three characteristics can greatly impact the resulting chemical, physical, and mechanical properties. While many techniques are available to determine polymer composition and size, determining the exact polymer architecture is more challenging. Herein, tandem mass spectrometry (MS/MS) and ion mobility mass spectrometry (IM-MS) methods are utilized to derive crucial architectural information about dithiol-yne comb polymers. Based on their unique fragmentation products and IM drift times, dithiol-yne oligomers with distinct architectures were successfully differentiated and characterized. Additionally, experimental collision cross-sections (Ω) derived via IM-MS were compared to theoretically extracted Ω values from molecular dynamics simulated structures to deduce the architectural motif of these comb oligomers. Overall, this work demonstrates the benefits of combining various mass spectrometry techniques in order to gain a complete understanding of a complex polymer mixture.

PTFE-g-GMA graft copolymer synthesis promoted by oxidative gamma-rays method and characterization

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.Graphical abstract

Preparation and Properties of Polyaniline/Hydroxypropyl Methylcellulose Composite Conductive Thin Films.

In this work, a chemical grafting polymerization method was employed to synthesize EHPMC-g-PANI self-supporting films. Polyaniline (PANI) was grafted onto hydroxypropyl methylcellulose (HPMC) modified with epichlorohydrin (EPHMC) to obtain an EHPMC-g-PANI aqueous dispersion, which was subsequently dried to form the self-supporting films. The introduction of HPMC, with its excellent film-forming ability and mechanical strength, successfully addressed the poor film-forming ability and mechanical properties intrinsic to PANI. Compared to in situ polymerized HPMC/PANI, the EHPMC-g-PANI exhibited significantly improved storage stability. Moreover, the fabricated EHPMC-g-PANI films displayed a more uniform and smoother morphology. The conductivity of all the films ranged from 10-2 to 10-1 S/cm, and their tensile strength reached up to 36.1 MPa. These results demonstrate that the prepared EHPMC-g-PANI holds promising potential for applications in various fields, including conductive paper, sensors, and conductive inks.

Synthesis and study of free radical graft polymerization of glycidyl methacrylate on gamma-irradiated graphene oxide

This study reports on the synthesis of a novel poly (glycidyl methacrylate) (PGMA) grafted graphene oxide (GO) by using a free radical-induced emulsion graft polymerization method. PGMA was grafted onto a gamma irradiated and vinyl functionalized GO substrate, and the parameters of graft polymerization (i.e., the concentration of monomer, initiator, and surfactant) were optimized to achieve the maximum grafting percentage. Remarkably, a PGMA grafting percentage of up to 2626 % was obtained under the optimal reaction conditions. The developed materials were characterized by different characterization techniques including Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The presence of characteristic peaks of PGMA in FTIR spectra and changes in morphology of GO sheets after the grafting process confirmed the successful PGMA grafting onto GO. The thermal stability of the grafted samples was also significantly enhanced and increased with an increase in grafting percentage. This work discloses the tailoring of the properties of nanohybrid material obtained by free radical-induced emulsion graft polymerization. The prepared PGMA grafted GO nanohybrids can be further modified to develop adsorbents for metal uptake.

Inhibition of wax crystallization and asphaltene agglomeration by core-shell polymer@SiO2 hybride nano-particles

The gelation of crude oil with high wax and asphaltene content at low temperatures often results in the block of transportation pipeline in Africa. In recent years, it was reported that surface hydrophobic-modified nanoparticles have important applications in crude oil flow modification. In this work, four kinds of core-shell hybride nanoparticles by grafting poly (octadecyl, docosyl acrylate) and poly (acrylate-α-olefin) onto the surface of nano-sized SiO2 were synthesized by grafting polymerization method. The chemical structure of nanoparticles was analyzed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The rheological behaviors of crude oil and precipitation of asphaltenes in the presence of nanoparticles were studied by measuring the viscose-temperature relationship curve, the cumulative wax precipitation amount, and morphology of waxes and asphaltenes. The results indicate that the docosyl polyacrylate@SiO2 nanoparticle (PDA@SiO2) can reduce the cumulative wax precipitation amount of crude oil by 72.8%, decline the viscosity of crude oil by 85.6% at 20 °C, reduce the average size of wax crystals by 89.7%, and inhibit the agglomeration of asphaltene by 74.8%. Therefore, the nanoparticles not only adjust the crystalline behaviors of waxes, but also inhibit the agglomeration of asphaltenes. Apparently, core-shell hybride nanoparticles provides more heterogeneous nucleation sites for the crystallization of wax molecules, thus inhibiting the formation of three-dimensional network structure. The core-shell polymer@SiO2 hybride nanoparticles are one of promising additives for inhibiting crystallization of waxes and agglomeration of asphaltenes in crude oil.

Recycling leachate nanofiltration concentrate and preparing a novel and low-cost absorbent dried gel by graft polymerization

Leachate nanofiltration concentrate (LNC), characterized by its complex composition and recalcitrant contaminants, poses a significant environmental challenge. This study explores the synthesis of absorbent gels via free radical polymerization, utilizing LNC as the solvent. Employing urea as the modified material, acrylic acid (AA) as the monomer, N, N′-Methylenebisacrylamide (MBA) as the cross-linking agent, and potassium persulfate (KPS) as the initiator, the resulting gel is stable below 180 °C. It demonstrates an impressive absorbency (Q) exceeding 14.50 g/g with key gel synthesis conditions optimized via response surface methodology (RSM). Subsequent application of the prepared LNC gel in LNC treatment via low-temperature evaporation achieves remarkable pollutant removal, meeting relevant water quality standards. This gel-based LNC treatment method achieves notable reductions in carbon emission and cost to 39.2 kgCO2/kgCOD and 3.4 $/kgCOD, respectively. This study provides a cost-effective and environment-friendly approach for LNC reutilization, and exemplifies the concept of utilizing waste to treat waste, thereby mitigating environmental impact of LNC and advancing gel technology in environmental remediation.

Epoxidized Soybean Oleic Acid/Oligomeric Poly(lactic acid)-Grafted Nano-Hydroxyapatite and Its Role as a Filler in Poly(L-lactide) for Potential Bone Fixation Application.

One of the most effective strategies for modifying the surface properties of nano-fillers and enhancing their composite characteristics is through polymer grafting. In this study, a coprecipitation method was employed to modify hydroxyapatite (HAP) with epoxidized soybean oleic acid (ESOA), resulting in ESOA-HAP. Subsequently, oligomeric poly(lactic acid) (OPLA) was grafted onto the surface of ESOA-HAP, yielding OPLA-ESOA-HAP. HAP, ESOA-HAP, and OPLA-ESOA-HAP were comprehensively characterized. The results demonstrate the progressive grafting of ESOA and OPLA onto the surface of HAP, resulting in enhanced hydrophobicity and improved dispersity in organic solvent for OPLA-ESOA-HAP compared to HAP. The vitality and adhesion of Wistar rat mesenchymal stem cells (MSCs) were assessed using HAP and modified HAP materials. Following culture with MSCs for 72 h, the OPLA-ESOA-HAP showed an inhibition rate lower than 23.0% at a relatively high concentration (1.0 mg/mL), which is three times lower compared to HAP under similar condition. The cell number for OPLA-ESOA-HAP was 4.5 times higher compared to HAP, indicating its superior biocompatibility. Furthermore, the mechanical properties of the OPLA-ESOA-HAP/PLLA composite almost remained unaltered ever after undergoing two stages of thermal processing involving melt extrusion and inject molding. The increase in the biocompatibility and relatively high mechanical properties render OPLA-ESOA-HAP/PLLA a potential material for the biodegradable fixation system.

Coal gasification slag for preparation of environmentally friendly superabsorbent composites with rapid water absorption and salt tolerance

It is crucial to design the novel low-cost and salt-tolerant superabsorbent for safeguarding food security and achieving sustainable agriculture. Herein, the porous superabsorbent composites with excellent salt tolerance were fabricated by redox-initiated grafting polymerization using water-based Pickering foam template co-stabilized with solid waste of coal gasification slag and plant particles Sapindus mukorossi pericarp. The stabilization mechanism of Pickering foams, swelling performance and salt-resistance of porous superabsorbent composites were studied in detail. Due to the abundant porous structure and the presence of coal gasification slag, the obtained superabsorbent composites exhibited rapid swelling rate and excellent water absorption capability, and the maximum water absorption in distilled water and 0.9 wt% NaCl solution reached 910 g/g and 126 g/g after 30 min, respectively. As 1.5 wt% the optimal superabsorbent composites was added into the saline-alkali soil, the growth of cabbages was significantly improved, and the plant height and chlorophyll content increased by 45.0% and 12.5%, respectively. This work served as a significant reference for preparing novel environmentally friendly water-saving materials for arid saline-alkali soil improvement.

Optimizing Binding among Bimolecular Tethered Complexes.

Tethered motion is ubiquitous in nature, offering controlled movement and spatial constraints to otherwise chaotic systems. The enhanced functionality and practical utility of tethers has been exploited in biotechnology, catalyzing the design of novel biosensors and molecular assembly techniques. While notable technological advances incorporating tethered motifs have been made, a theoretical gap persists within the paradigm, hindering a comprehensive understanding of tethered-based technologies. In this work, we focus on the characterization of the binding kinetics of two tethered molecules functionalized to a hard surface. Using a mean-field approximation, the binding time of such bimolecular system is determined analytically. Furthermore, estimates of the grafting site separation and polymer lengths which expedite binding are provided. These estimates, along with the analytical theories and frameworks established here, have the potential to improve efficacy in self-assembly methods in DNA nanotechnology and can be extended to more biologically specific endeavors including targeted drug-delivery and molecular sensing.

Preparation and Performance Study of Boron Adsorbent from Plasma-Grafted Polypropylene Melt-Blown Fibers.

In this study, the plasma graft polymerization technique was used to graft glycidyl methacrylate (GMA) onto polypropylene (PP) melt-blown fibers, which were subsequently aminated with N-methyl-D-glucamine (NMDG) by a ring-opening reaction, resulting in the formation of a boron adsorbent denoted as PP-g-GMA-NMDG. The optimal conditions for GMA concentration, grafting time, grafting temperature, and the quantity of NMDG were determined using both single factor testing and orthogonal testing. These experiments determined the optimal process conditions to achieve a high boron adsorption capacity of PP-g-GMA-NMDG. Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersion spectrum analysis (EDS), and water contact angle measurements were performed to characterize the prepared adsorbent. Boron adsorption experiments were carried out to investigate the effects of pH, time, temperature, and boron concentration on the boron adsorption capacity of PP-g-GMA-NMDG. The adsorption isotherms and kinetics of PP-g-GMA-NMDG for boron were also studied. The results demonstrated that the adsorption process followed a pseudo-second-order kinetic model and a Langmuir isothermal model. At a pH of 6, the maximum saturation adsorption capacity of PP-g-GMA-NMDG for boron was 18.03 ± 1 mg/g. In addition, PP-g-GMA-NMDG also showed excellent selectivity for the adsorption of boron in the presence of other cations, such as Na+, Mg2+, and Ca2+, PP-g-GMA-NMDG, and exhibited excellent selectivity towards boron adsorption. These results indicated that the technique of preparing PP-g-GMA-NMDG is both viable and environmentally benign. The PP-g-GMA-NMDG that was made has better qualities than other similar adsorbents. It has a high adsorption capacity, great selectivity, reliable repeatability, and easy recovery. These advantages indicated that the adsorbents have significant potential for widespread application in the separation of boron in water.