Methacrylate Copolymers Research Articles

All-In-One Epoxy/MXene Nanocomposites with Bead-Type Polymeric Imidazole Latent Curing Agent for Enhancing Storage Stability and Flame Retardancy.

Developing a single-component epoxy system is challenging but crucial for advanced thermoset applications. Unfortunately, conventional latent curing agents using chemical or physical passivation do not provide satisfactory storage stability and the necessary property requirements. Here, it is demonstrated that all-in-one epoxy/MXene nanocomposite system, comprising epoxy resin, polymeric imidazole latent curing agent beads (PILCAB), and Ti3C2Tx MXene, exhibits excellent storage stability, improved flame retardancy, and enhanced mechanical strength. PILCABs, prepared through a Diels-Alder (DA) crosslinking reaction between furan groups of poly(imidazolyl methacrylate)-random poly (furfuryl methacrylate) (PIm-r-PFu) copolymer and bismaleimide (BMI), exhibit excellent storage stability, as stable as under 60 °C storage due to the imidazole reactivity being suppressed synergistically by both physical and chemical passivation mechanisms. Ti3C2Tx MXene flakes, surface-functionalized with alkylated 3,4-dihydroxyl-L-phenylalanine, exhibit excellent compatibility with the epoxy matrix. Consequently, the enhanced storage stability, flame retardancy, and mechanical strength of the all-in-one epoxy/MXene nanocomposite are attributed to the strong DA bond formation in latent curing agent, efficient charring capability of MXene and BMI, and the catalytic effect of the MXene. This study opens new avenues for designing and developing single-component epoxy systems that satisfy demanding requirements, including storage stability, mechanical strength, and flame retardancy, which are essential for practical applications.

Solid-state solvatochromism of oxazolidine in multi-functionalized copolymer nanoparticles: Development of advanced materials with multi-color fluorescence

Investigating the solvatochromism of stimuli-chromic compounds such as oxazolidine in polymer matrices with various polarities or functionalities is a unique approach to developing advanced materials for anticounterfeiting, sensor, optoelectronic, and displayers. In a novel strategy, multi-functionalized copolymer nanoparticles were synthesized by copolymerization of methyl methacrylate (MMA) with various functional comonomers in emulsion media for post-polymerization modification with oxazolidine and investigation of its solvatochromism in both colloidal solution and solid phase. The particle size and morphology of nanoparticles were influenced significantly by the polarity of functional groups, and the morphology evolution from sphere to anisotropic shapes was observed by increasing the polarity of functional groups. Investigation of oxazolidine solvatochromism in colloidal solution and solid polymer powders indicated different mechanisms for solvatochromism, in which the polarity of media is the main effective parameter in colloidal solution and the polarity of functional groups in the polymer structure is the main effective parameter in solid polymer phase. The solvatochromism of oxazolidine was confirmed by observed red shift and blue shift in UV–Vis and fluorescence spectra, in which the intensity of absorbance and emission peaks was changed as a function of the polarity of functional groups. Solvatochromic photoluminescent polymer nanoparticles were used for several advanced applications such as solid anticounterfeiting inks to information encryption, dual-mode visualization of latent fingerprints, and also development of organic light-emitting diodes (OLEDs). For the first time, the results indicate a significant effect of polymer chain local polarity induced by functional groups on the tuning of optical properties of the oxazolidine by the solid-state solvatochromic phenomenon. Solvatochromism of oxazolidine in functionalized polymer nanoparticles is an interesting approach to developing novel intelligent materials that have advanced applications in different fields such as anticounterfeiting and information encryption, optoelectronic, polarity sensor, and visualization of latent fingerprints.

Novel Photobase Generators Derived from Proazaphosphatrane–Aryl Borate for High‐Pressure Mercury Lamp Lithography

AbstractHerein, novel borate‐type photobase generators (PBGs) that generate a proazaphosphatrane known as Verkade's base (2,8,9‐triisobuthyl‐2,5,8,9‐tetraaza‐1‐phosphabicyclo[3.3.3]undecane (TTP)) were developed for photopatterning using a high‐pressure mercury lamp. Eight PBGs were synthesized, each featuring distinct borate substituents: phenyl, p‐fluorophenyl, p‐tolyl, p‐methoxyphenyl, m‐fluoro‐p‐methylphenyl, 4‐biphenyl, 2‐naphthyl, and 6‐methoxy‐2‐naphthyl. The relation between these substituents and their light absorption characteristics was analyzed via ultraviolet–visible spectroscopy and time‐dependent density functional theory calculations. The PBG with the 6‐methoxy‐2‐naphthylborate group (TTP–tetrakis[2‐(6‐methoxynaphthyl)]borate (TTP–TMNB)) demonstrated substantial light absorption near 365 nm (the i‐line of the high‐pressure mercury lamp), generating approximately 60 % of the corresponding TTP in deuterated tetrahydrofuran (THF) upon exposure to 650 mJ/cm2, as confirmed via 1H nuclear magnetic resonance spectroscopy. To evaluate its photolithographic potential, TTP–TMNB was mixed with epoxy resin (jER1001) and a poly(methacrylic acid)‐co‐poly(methyl methacrylate) copolymer (PMA1.6‐co‐PMMA100) in THF. The resulting mixture was spin‐coated onto a silicon wafer and irradiated with the i‐line through a photomask to create a negative‐tone image. The sensitivity and contrast of this photopolymer system were measured to be 45 mJ/cm2 and 1.0, respectively; moreover, a clear 10‐μm negative‐tone resolution was achieved.

Formation of Superhydrophobic Coatings Based on Dispersion Compositions of Hexyl Methacrylate Copolymers with Glycidyl Methacrylate and Silica Nanoparticles.

In the last decade, the task of developing environmentally friendly and cost-effective methods for obtaining stable superhydrophobic coatings has become topical. In this study, we examined the effect of the concentrations of filler and polymer binder on the hydrophobic properties and surface roughness of composite coatings made from organic-aqueous compositions based on hexyl methacrylate (HMA) and glycidyl methacrylate (GMA) copolymers. Silicon dioxide nanoparticles were used as a filler. A single-stage "all-in-one" aerosol application method was used to form the coatings without additional intermediate steps for attaching the adhesive layer or texturing the substrate surface, as well as pre-modification of the surface of filler nanoparticles. As the ratio of the mass fraction of polymer binder (Wn) to filler (Wp) increases, the coatings show the lowest roll-off angles among the whole range of samples studied. Coatings with an optimal mass fraction ratio (Wn/Wp = 1.2 ÷ 1.6) of the filler to polymer binder maintained superhydrophobic properties for 24 h in contact with a drop of water in a chamber saturated with water vapor and exhibited roll-off angles of 6.1° ± 1°.

Light-responsive zwitterionic membrane surface modification for antifouling and antibacterial application

Light-responsive surface modifications offer a promising solution for reducing membrane fouling by enabling remote, contactless cleaning without altering the chemical environment. While traditional methods make membranes hydrophilic to resist fouling, biofouling remains difficult to remove and often requires harsh bactericidal treatments. With the rise of antimicrobial resistance (AMR), there is a pressing need for alternative, non-bactericidal strategies to control biofilm growth. In this study, we developed an efficient approach by coating commercial ultrafiltration polyethersulfone (PES) membranes with a copolymer of light-responsive azobenzene (AZO) and zwitterionic sulphobetaine methacrylate (SBMA). The photochemical conversion efficiency and photokinetic parameters of the copolymer, due to light-induced trans–cis-trans conversion, were systematically determined. During filtration, the modified membranes showed excellent resistance to reversible fouling with bovine serum albumin (BSA). The fouled membrane became reusable after near-complete removal of irreversible fouling, including bacteria (Pseudomonas aeruginosa), by activating the AZO units with UV–vis light, providing an effective strategy for fouling control.

Mechanical and Dimensional Stability of Gelatin-Based Hydrogels Through 3D Printing-Facilitated Confined Space Assembly.

Hydrogels have emerged as promising biomaterials for tissue regeneration; yet, their inherent swelling can cause deformation and reduced mechanical properties, posing challenges for practical applications in biomedical engineering. Traditional methods to reduce hydrogel swelling often involve complex synthesis procedures with limited flexibility. Inspired by nature's efficient designs, we present here the approach to improve hydrogel performance using 3D printing-assisted microstructure engineering. By utilizing polymerization-induced phase separation of hydrogel from copolymerization of gelatin methacrylate and hydroxyethyl methacrylate (poly(GelMA-co-HEMA)) in the confined space during vat photopolymerization (VPP) 3D printing, we replicate the cuttlebone-like microstructure of hydrogels with enhanced mechanical properties and swelling resistance. We demonstrate here a 4-fold increase in elastic modulus compared to bulk polymerization of poly(GelMA-co-HEMA), together with improved mechanical and dimensional stability. This method offers promising opportunities for practical biomedical and tissue engineering applications, overcoming previous limitations in the design and performance.

Thermoreversible Apparel Adhesives to Enable Sustainable Garment Assembly

AbstractOver 90 million tons of fabric waste are generated annually by the apparel industry and there exists an urgent need to develop innovative approaches for the recycling of garments. Reversible adhesives can both enable the automation of labor‐intensive assembly processes and facilitate fabric recycling for a circular apparel economy. Herein, an adhesive formulation based on thermoreversible Diels–Alder chemistry has been developed via the combination of a furan‐functionalized methacrylate copolymer (F) with a bismaleimide (M). To establish the fine balance between adhesion strength and reversible bonding, an extensive screening on the optimal composition and molar mass of F is conducted. Methyl, 2‐ethylhexyl, and lauryl methacrylate are used to tune the Tg of F copolymers, whereas H‐bonding monomers such as methacrylic acid and 2‐hydroxyethyl methacrylate are utilized to strengthen the adhesive and improve its interactions with cotton. Following the optimization of F composition, F molecular weight, and M crosslinker, the scaled‐up thermoreversible adhesive is studied by rheometry and successfully dispensed via an automated assembly platform. The adhered fabrics are tested for the required shear and peel strength and then separated for fabric recycling by a short heat treatment followed by a simple solvent wash to remove adhesive residues.

Effect of Star-like Polymer on Mechanical Properties of Novel Basalt Fibre-Reinforced Composite with Bio-Based Matrix.

This study is aimed at developing a fibre-reinforced polymer composite with a high bio-based content and to investigate its mechanical properties. A novel basalt fibre-reinforced polymer (BFRP) composite with bio-based matrix modified with different contents of star-like n-butyl methacrylate (n-BMA) block glycidyl methacrylate (GMA) copolymer has been developed. n-BMA blocks have flexible butyl units, while the epoxide group of GMA makes it miscible with the epoxy resin and is involved in the crosslinking network. The effect of the star-like polymer on the rheological behaviour of the epoxy was studied. The viscosity of the epoxy increased with increase in star-like polymer content. Tensile tests showed no noteworthy influence of star-like polymer on tensile properties. The addition of 0.5 wt.% star-like polymer increased the glass transition temperature by 8.2 °C. Mode-I interlaminar fracture toughness and low-velocity impact tests were performed on star-like polymer-modified BFRP laminates, where interfacial adhesion and impact energy capabilities were observed. Interlaminar fracture toughness improved by 45% and energy absorption capability increased threefold for BFRP laminates modified with 1 wt.% of star-like polymer when compared to unmodified BFRP laminates. This improvement could be attributed to the increase in ductility of the matrix on the addition of the star-like polymer, increasing resistance to impact and damage. Furthermore, scanning electron microscopy confirmed that with increase in star-like polymer content, the interfacial adhesion between the matrix and fibres improves.

PH‐sensitive size/surface charge‐adaptive quaternary ammonium salt copolymer micelles for antibiofilm activity against Staphylococcus aureus

AbstractThe low penetration of antibacterial materials within biofilms results in a 1000‐fold decrease in bactericidal efficiency, complicating the complete removal of biofilms and potentially leading to persistent and recurrent bacterial infections that significantly impact human health. In this study, we present a multifunctional pH‐responsive antibacterial material based on random copolymers poly(dimethylaminoethyl methacrylate decyl ammonium bromide‐co‐polyethylene glycol methacrylate) copolymer (PQACs10‐co‐PEGMA10). The PQACs10‐co‐PEGMA10 copolymers could self‐assemble into micelles in selective solvent water. With the stealth function of polyethylene glycol (PEG), the PQACs10‐co‐PEGMA10 micelles can rapidly penetrate biofilms in a physiological environment and exhibit excellent antibacterial activity by exposing the quaternary ammonium salt (QACs) in an acidic microenvironment to eliminate biofilm. Furthermore, PQACs10‐co‐PEGMA10 micelles were applied as coatings using a dropwise method. The PEG chain formed hydration layer and the QACs chain for sterilization can hinders bacterial adhesion and proliferation, thereby preventing biofilm formation. The results show that the minimal inhibit concentration values and minimum biofilm eradication concentrations of the PQACs10‐co‐PEGMA10 micelles against Gram‐positive Staphylococcus aureus were 64 and 128 μg/mL, respectively. The antifouling and antibacterial rates of micelle coating against S. aureus were more than 99.99%. Taken together, the pH‐responsive PQACs10‐co‐PEGMA10 micelles demonstrate a good ability to clear and prevent biofilms, holding promise for complete biofilm removal and a reduction in biofilm‐related infections.

Esophageal transit of solid oral dosage forms – impact of different surface materials characterized in vitro and in vivo by MRI in healthy volunteers

Acceptable swallowability and complete esophageal transit are decisive for the safe and effective administration of solid oral dosage forms. This applies in particular to the main user group of medicines, older adults, who often suffer from swallowing difficulties. It is well known that surface properties play an important role in this respect. In the past, this has led to the development of numerous coating formulations for tablets with improved swallowability. However, in vitro and especially in vivo data investigating a positive effect of different coating materials is limited. Therefore, we investigated coating materials being based on polyvinyl alcohol, hydroxypropyl methylcellulose, and a copolymer of methacrylate in respect to their influence on swallowability and esophageal transit of a tablet formulation. They were compared to uncoated tablets as well as to hard gelatin capsules. Three in vitro assays suitable for routine use in pharmaceutical development were performed: i.) Wettability test in artificial saliva; ii.) Swelling measurement in artificial saliva; iii.) Measurement of the adhesion between surface materials and a simulated mucosa surface. All three assays resulted in a differentiation of the surface materials. The coated tablets showed favorable behavior compared to uncoated tablets and hard gelatin capsules. To test the effect of the different materials in vivo, an intervention study was conducted. 36 adults were included and the likeliness of prolonged esophageal transit of (un-)coated tablets as well as a hard gelatin capsule of the same weight was objectively evaluated by means of magnetic resonance imaging. While hard gelatin capsules showed highest rates for prolonged esophageal transit, the tendency for adhesion was reduced for uncoated tablets, and least for coated tablets, i.e., prolonged esophageal transit in 22.2 %, 11.1 %, and ≤5.6 % of the cases, respectively. Further differentiation of the coating materials was not possible. Subjective evaluations of each participant with respect to subjective swallowability and esophageal transit did not correlate well with the objective measurements by means of magnetic resonance imaging. The use of coatings in general has a positive influence on esophageal transit. However, the selection of coating type seems to be of greater importance in respect to patients' oral perception of the dosage forms compared to their influence on the probability for prolonged esophageal transit.

Evaluation of a novel non-ionic graft starch-based antiscalant in reduction of CaSO4 scaling by static and reverse osmosis test

A novel nonionic starch-based antiscalant (St-g-GMA) was designed and obtained by graft copolymerization of starch and glycidyl methacrylate (GMA). St-g-GMA not only achieved an obvious reduction of CaSO4 scaling in static test, but also effectively mitigated the flux decrease in dynamic reverse osmosis (RO) system. This improvement is ascribed to the grafted poly(GMA) chains on St-g-GMA. A suitable grafting ratio of this starch-based antiscalant achieve a high performance cost in control of CaSO4 scaling. Combination of the apparent antiscaling performance, observation under scanning electron microscopy, energy dispersive x-ray spectroscopy unit, x-ray diffraction pattern, conductivity measurement, and dispersion experiment, the scale-inhibition mechanism of St-g-GMA was investigated and mainly attributed to chelation, dispersion and lattice distortion effects. The oxygen-containing groups on poly(GMA) chains such as epoxy groups can chelate with Ca2+, causing the induction time of crystallization prolonged; St-g-GMA with the distinct branched chain configuration can well disperse the formed microcrystal of CaSO4. Moreover, molecular dynamics simulations confirmed that the grafted poly(GMA) chains well bind to the crystal surfaces and the oxygen-containing groups could even enter the crystal lattice to inhibit the crystal growth and change the morphologies. St-g-GMA still mitigated the flux decrease notably in treatment of a synthetic seawater during a 24-h RO measurement. This study provided an efficient, environmentally-friendly and low-cost antiscalant with high application potentials.

Preparation of high transparency, thermal stability, flame retardant polymethyl methacrylate nanocomposite via gamma-radiation polymerization

Achieving flame retardancy and thermal stability in poly(methyl methacrylate) (PMMA) while maintaining its inherent high transparency presents a significant challenge. In this work, we successfully fabricated an exceptional composite (P-SiO2-PMMA) with high transparency, flame retardancy, and thermal stability using 60Co γ-ray irradiation-induced copolymerization of methyl methacrylate (MMA), 2-hydroxyethyl 2-methyl-2-propenoate phosphate (HEMAP), and nano-silica (SiO2). The impact of the HEMAP on the crystal, optical, thermal stability, and combustion behavior properties of P-SiO2-PMMA has been investigated. P-SiO2/PMMA forms a three-dimensional network cross-linked molecular chain structure, enhancing the thermal decomposition temperature (Tdi), maximum thermal decomposition temperature (Tmax), glass transition temperature (Tg), and reducing the coefficient of thermal expansion (CTE). HEMAP and SiO2 significantly enhance the flame retardancy of the material. The limiting oxygen index (LOI) value of transparent flame-retardant 20-P-SiO2/PMMA composite material increased from 17.5% for PMMA to 23.2%, with a 47.3% decrease in peak heat release rate (PHRR). The flame retardant mechanism was also investigated. This study offers a novel approach for the industrial application of high transparency, thermal stability, and halogen-free flame-retardant PMMA composite.

A highly stretchable and self-adhesive cellulose complex hydrogels based on PDA@Fe3+ mediated redox reaction for strain sensor

As the application of conductive hydrogels in the field of wearable smart devices is gradually deepening, a variety of hydrogel sensors with high mechanical properties, strong adhesion, fast self-healing, and excellent conductivity are emerging. However, it is still a great challenge to manufacture hydrogel sensors combining multiple properties. Herein, we leveraged the dynamic redox reaction occurring between polydopamine (PDA) and Fe3+ to induce ammonium persulfate (APS) to generate free radicals, thereby initiating the copolymerization of hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) monomers. Then, polypyrrole-encapsulated cellulose nanofibers (PPy@CNF) and carboxymethylcellulose (CMC) were incorporated as conductive reinforced nanofillers and interpenetrating network skeleton. The obtained hydrogel cross-linked through reversible metal-ligand bonds, π-π stacking and abundant hydrogen bonding demonstrated great mechanical properties (strength 240.4 kPa, strain 1175 %) and self-healing ability (88.96 %). Particularly, the gel displayed ultrahigh durability and skin adhesive ability (75 kPa after 10 cycles), surpassing previous skin adhesion hydrogels. Furthermore, through the synergistic conductive effect of PPy@CNF and Fe3+, the prepared hydrogel sensor possessed high sensitivity (GF = 1.89) with a wide sensing range (~1000 %), which could realize the human body's daily motion detection, and had a promising application in flexible wearable electronics.

Thermally-responsive dismantlable adhesion system for steel plates using methacrylate copolymers containing a tert-butoxycarbonyl group

A drastic change in the bulk properties of adhesive materials as well as a reduction of interfacial interaction is an important key for the development of dismantlable adhesion systems, i.e., reliable bonding systems with a function of on-demand debonding. The deprotection of tert-butoxycarbonyloxy (BOC) groups included in adhesive polymers can be applied to the construction of a dismantlable adhesion system for steel plates combined with acrylic and epoxy adhesives. In this study, we evaluated the adhesive properties of the copolymers of 2-(tert-butoxycarbonyloxy)ethyl methacrylate (BHEMA), glycidyl methacrylate (GMA), and 3-trimethoxysilylpropyl methacrylate (SMA) for the dismantlable bonding of steel plate cold commercial (SPCC). Spontaneous dismantling of the SPCC adhesive structures was achieved after heat treatment under the conditions at 210 °C for 15 min when the BHEMA/GMA/SMA copolymers with an appropriate copolymer composition were used as the acrylic adhesives or the primers for epoxy adhesion. We discuss the interfacial interactions between the adherend and the adhesives for reliable adhesion and the effects of the deprotection of the BOC groups for dismantling to exhibit both an adhesion strength required for metal bonding and a rapid decrease in the strength by thermal stimulus.

Precision synthesis of diblock copolymers via free radical photopolymerization.

Diblock copolymers of phenyl methacrylate (PMA) and butyl methacrylate (BMA) were synthesized using dual-wavelength photopolymerization with a bifunctional photoinitiator 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl(E)-3-(1-methyl-1H-pyrrol-2-yl)acrylate (PAA-2959).

3D-printed copolymer semi-cavity sensor with inner optical filter-effecting quantum dots photoluminescence for multiple drugs and amino acids detection

Here, we demonstrate a prototype for a novel optical sensor based on 3D-printed copolymer semi-cavity embedded with colloidal ZnCuInS (ZCIS) quantum dots (QDs) and utilizing the optical filter-effect in the QDs photoluminescence excitation pathway by analytes in the solution. First, in situ copolymerization of styrene and n-butyl methacrylate (P(S-BMA)) with colloidal ZCIS QDs allowed formation of solid P(S-BMA) matrix homogeneously impregnated with QDs. Then QDs@P(S-BMA) mixed with polylactic acid (PLA) has been processed into QDs@P(S-BMA)@PLA hybrid filaments using extruder. Then, a semi-cavity optical cell was 3D-printed out of QDs@P(S-BMA)@PLA filaments. Such 3D-printed semi-cavity cell can be used as the optical sensor on various molecules utilizing the optical absorption by analyte molecules through inner filter effect (IFE) of a properly selected QDs excitation beam. The multiple drug and amino acid molecules have been utilized having selective UV absorption to examine our proof of concept.

Development and Analysis of Colon-Specific, pH-Responsive Polymer Delivery of Irinotecan Hydrochloride Tablets for Colon Cancer Treatment.

For the formulation of enteric-coated tablets containing irinotecan hydrochloride, this thesis focuses on HPMC and ethylcellulose, both of which are pH- and oxidation-resistant polymers. The integrated polymer-drug tablet mixture was coated with 15% of eudragit S100 and L100, which is a methacrylic acid copolymers, that’s soluble at pH 7. Both the physical characteristics with the invitro release kinetics pattern of the enteric-coated tablets were characterized. In the invitro release study, different pH environments were used, comparable to the gastrointestinal tract (GIT): 0.1 N HCl solution for two hours, pH 6.8 phosphate buffer for three hours, and pH 7.4 phosphate buffer for six hours. Using this device, you can simulate the pH level of the mouth, the digestive tract, and the urinary tract. As a result of consistent release studies, formulation F7 released 88.2% of the drug after 12 hours. Models such as Higuchi, Korsmeyer-Peppas, and zero-order reactions were used to analyze the GIT. This directed the development of a sustained delivery pattern that may be perfect for colonic IRT administration in the eventual treatment of colon cancer. Among the nine formulations, F7 formulated with EC and HPMC extended best sustained release pattern of drug, hence it is suitable for treating colon cancer.

PH‐responsive bionanocomposite pectin grafted with dimethylaminoethyl methacrylate and acrylic acid copolymer along with silver nanoparticles for breast cancer drug delivery

AbstractIn this study, we developed a pH‐responsive hydrogel membrane composed of pectin, dimethylaminoethyl methacrylate (DMAEMA), and acrylic acid (AA) through a free radical‐triggered graft copolymerization method. Freshly formed silver nanoparticles (AgNPs) produced from the reduction reaction were embedded in the produced hydrogel. Pectin‐grafted dimethylaminoethyl methacrylate and acrylic acid copolymer [poly (DMAEMA‐co‐AA)‐g‐pectin] and its bionanocomposite with AgNPs were confirmed by Fourier‐transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The swelling behavior of poly (DMAEMA‐co‐AA)‐g‐pectin in solutions with diverse pH values was assessed. For use as a controlled drug delivery agent, the hydrogel was loaded with 5‐fluorouracil (5‐FU). The incorporation of AgNPs had a great impact on the entrapment efficiency of 5‐FU. At pH 7.4, nearly 48% of the 5‐FU was released in vitro from the polymeric nanocomposite within 24 h. Moreover, poly (DMAEMA‐co‐AA)‐g‐pectin and poly (DMAEMA‐co‐AA)‐g‐pectin/AgNPs presented high cytocompatibility toward normal skin fibroblast cells (BJ1), and the drug delivery system strongly inhibited human Caucasian breast adenocarcinoma cells (MCF‐7). These results demonstrated that these poly (DMAEMA‐co‐AA)‐g‐pectin/AgNPs are an excellent candidate for use in anticancer drug delivery systems.Highlights Free radical polymerization of nanocomposites incorporated with nanoparticles. Nanoparticles improve the bionanocomposites' drug loading. The developed bionanocomposites exhibit control drug release. The novel bionanocomposites acts as an excellent anticancer drug carrier.

Synthesis and Porous Structure Characteristics of Allyl Methacrylate/Divinylbenzene Polymers

A set of six porous copolymers of allyl methacrylate (AllMeth) and divinylbenzene (DVB), containing 5 to 50 wt% of the latter crosslinker, are synthesized by suspension polymerization method in the presence of inert diluents. Obtained polymers have various specific surface areas—those with 20 to 50 wt% of DVB have a high surface area in the range of 410–480 m2/g, depending only slightly on the amount of the aromatic crosslinker. Specific surface area decreases strongly only when DVB content is 15 and 5 wt%. That is the feature that is unusual for crosslinked polymers and indicates the participation of allyl groups in making a novel polymeric network of high porosity. All polymers contain polar carbonyl groups, with an electron pair able to interact with polar sorbates. Polymers are characterized using elemental analysis, FTIR, and their porous structure is characterized by nitrogen adsorption at 77 K. All polymers contain residual allyl groups, which possibly can serve as convenient points for chemical modification, allowing for the future synthesis of specialty polymers (such as ion-exchangers and coordinating resins).

Conductive, sensitivity, flexibility, anti-freezing and anti-drying silica/carbon nanotubes/sodium ions modified sodium alginate hydrogels for wearable strain sensing applications

The biocompatibility and salient gelling feature of alginate via forming the interpenetrating network structure has received extensive interests for different applications. Traditional alginate hydrogels freeze at low temperature and evaporate easily at room temperature, leading to reduced performance. Consequently, it is crucial to develop methods to prevent alginate hydrogel from freezing at subzero temperature and dehydration at normal temperature to maintain the performance stability. Utilizing polyacrylic acid, sodium alginate, and acrylamide-hydroxyethyl methacrylate copolymers as flexible matrix materials, this study develops a wearable silica (SiO2)/carbon nanotubes (CNT)/sodium ions (SiO2/CNT/Na+) modified sodium alginate hydrogel strain sensor characterized by high sensitivity, flexibility, and anti-freezing and anti-drying properties. The hydrogel doped with NaCl (50 mg), CNT (10 mg) and M-SiO2 (200 mg) shows excellent mechanical and electrical properties, the tensile strength is 436 KPa, the break elongation is 426 %, the elastic modulus is 99 KPa, and the toughness is 897 kJ/m3. The modified sodium alginate hydrogel used as strain sensor shows fast response time (∼100 ms), high sensitivity factor and excellent stability. The strain sensor exhibits excellent flexibility, ductility, self-adhesion, anti-freezing and anti-drying properties, significantly enhancing its strain sensing application field.