Poly Methacrylic Acid Research Articles

Structure and dynamics of poly(methacrylic acid) and its interpolymer complex probed by covalently bound rhodamine-123

The dynamics and structural characteristics of polymethacrylic acid bound rhodamine-123 (PMAA–R123) and its interpolymer complex formed through hydrogen bonding between the monomeric units with poly(vinylpyrrolidone) were investigated using single molecular fluorescence studies. The time resolved fluorescence anisotropy decay of PMAA-R123 under acidic pH exhibits an associated anisotropy decay behavior characteristic of two different environments experienced by the fluorophore with one shorter and another longer rotational correlation time. The anisotropy decay retains normal bi-exponential behavior under neutral pH. Fluorescence correlation spectroscopic investigation reveals that the attached fluorophore undergoes hydrolysis under basic condition which results in the release of the fluorophore from the polymer backbone. Shrinkage in the hydrodynamic radius of PMAA is observed on addition of the complementary polymer PVP which is attributed to the formation compact solubilized nanoparticle like aggregates. The size of particle further decreases on the addition of NaCl. The detailed results show that these complexes have potential for use as drug-delivery system under physiological conditions.

Poly-Methacrylic Acid Cross-Linked with Collagen Accelerates Diabetic Wound Closure.

Impaired blood vessel formation limits the healing of diabetic ulcers and leaves patients at high risk for amputation. Nonbiologic vascular regenerative materials made of methacrylic acid (MAA) copolymer, such as MAA-co-methyl methacrylate beads, have shown to enhance wound healing in a diabetic animal model, but their lack of biodegradability precludes their clinical implementation. Here, a new MAA-based gel was created by cross-linking polyMAA with collagen using carbodiimide chemistry. Using this gel on full-thickness wounds in diabetic db/db mice augmented vascularization of the wound bed, resulting in a faster closure compared to untreated or collagen-only treated wounds. After 21 days, almost all the wounds were closed and re-epithelialized in the polyMAA-collagen group compared to that in the other groups in which most wounds remained open. Histological and fluorescent gel tracking data suggested that the gel resorbed during the phase of tissue remodeling, likely because of the action of macrophages that colonized the gel. We expect the addition of the polyMAA to commercially available collagen-based dressing to be a good candidate to treat diabetic ulcers.

Determination of Free Glycerol in Biodiesel by Molecularly Imprinted Polymer – Based Solid-Phase Extraction (SPE) Using an Enzymatic Spectrophotometric Assay

The present work reports the development of a new analytical method for the determination of free glycerol in biodiesel samples using enzymatic-spectrophotometric assay combined with solid phase extraction (SPE) by molecularly imprinted poly(methacrylic acid) (MIP). The spectrophotometric method was performed using a commercial enzyme kit. The enzymatic-spectrophotometric method showed good analytical performance in terms of the linearity (0.998), limit of detection (7.70 × 10−6% w/w), limit of quantification (2.54 × 10−5% w/w), repeatability (0.42% to 7.91%), and recovery (99.4% to 112%). The analyses of several biodiesel samples by SPE and enzymatic-spectrophotometric method provided recovery values between 91.4% and 105%. Therefore, the high selectivity of molecularly imprinted polymer (MIP) was successfully applied to isolate free glycerol from biodiesel samples containing acylglycerols and methyl esters, and thereby allow enzymatic-spectrophometric based quantification. The developed method using SPE with MIP was efficient for the determination of free glycerol in biodiesel and the obtained results are in agreement with gas chromatrography (GC) that was used as a reference protocol.

Binary Nanosystems Based on Amphiphilic Molecular Brushes Loaded with Radachlorine® Photosensitizer or Selenium Nanoparticles

The morphology, optical, and molecular-conformation characteristics of amphiphilic molecular brushes with a polyimide main chain and poly(methacrylic)acid acid side chains loaded with the second-generation photosensitizer Radachlorine® or a biogenic element (selenium in the zero-valence form Se0) nanoparticles are studied using atomic force microscopy, UV spectroscopy, and dynamic/static light scattering. The effect of density Z of grafts of poly(methacrylic)acid acid side chains and of the introduction of Radachlorine® or Se0 into amphiphilic molecular brushes on the size, spectral, and molecular conformation characteristics of synthesized binary nanosystems is demonstrated. A nonmonotonic dependence of the nanostructure size and the film surface roughness with increasing Z in binary systems with Radachlorine® and, conversely, a monotonic decrease in the nanostructure size and surface roughness for systems containing Se0 nanoparticles are observed.

Advancing spinal fusion: Interbody stabilization by in situ foaming of a chemically modified polycaprolactone.

Spinal fusion (SF) surgery relies on medical hardware such as screws, cages and rods, complemented by bone graft or substitute, to stabilize the interventioned spine and achieve adequate bone ingrowth. SF is technically demanding, lengthy and expensive. Advances in material science and processing technologies, proposed herein, allowed the development of an adhesive polymeric foam with the potential to dismiss the need for invasive hardware in SF. Herein, 3D foams of polycaprolactone doped with polydopamine and polymethacrylic acid (PCL pDA pMAA) were created. For immediate bone stabilization, in situ hardening of the foam is required; therefore, a portable high-pressure device was developed to allow CO2 foaming within bone defects. Foams were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Adhesive properties of PCL pDA pMAA outperformed PCL when tested using glass surfaces (p < 0.001) or spinal plugs (p < 0.05). No cytotoxicity was observed, and bioactivity was confirmed by the CaP layer formed upon 7 days immersion in simulated body fluid. As proof of concept, PCL pDA pMAA was extruded in-between ex vivo porcine vertebrae, and micro-computed tomography revealed similar properties to those of trabecular bone. This novel system presents great promise for instrumentation-free interbody fusion.

Features of sorption of rare-earth metals of cerium group by intergel systems based on polyacrylic acid, polymethacrylic acid and poly-4-vinylpyridine hydrogels

Features of sorption of rare-earth metals of cerium group by intergel systems based on polyacrylic acid, polymethacrylic acid and poly-4-vinylpyridine hydrogels

Luminescent silver nanoclusters for efficient detection of adenosine triphosphate in a wide range of pH values

In this work, polymethacrylic acid (PMAA)-templated silver nanoclusters (Ag NCs) were developed as the fluorescent probe for the efficient and sensitive detection of adenosine triphosphate (ATP) in a wide range of pH values. The fluorescence intensity of the Ag NCs could keep stable with pH values ranging from 2.5 to 9.3. The detection of ATP was based on the quenching of the fluorescent Ag NCs in the presence of ATP. The fluorescence quenching of the Ag NCs with increasing ATP concentration was studied at pH 2.5, 4.5, 7.0 and 8.5 which involved a wide pH environment in body fluids. The limit of detection (LOD) for ATP was as low as 0.1 mmol/L in an acidic environment with pH of 2.5 and all the linear correlation coefficients were satisfactory under wide-span pH values from 2.5 to 8.5. In addition, the sensitive determination of ATP was also achieved by adding copper ions (Cu2+). The high selectivity and rapid detection process proved that the fluorescent probe had great potential to detect ATP in biological samples under different pH conditions.

Poly Methacrylic Acid Sodium Salt (PMANa)/Polyurethane (PU) Latex-Polyelectrolyte Colloid Systems Enabling One-Pot Fabrication of Nonperiodic Structured Mechanoresponsive Smart Windows.

Mechanoresponsive smart windows can modulate optical transparency by mechanical actuation, showing the advantages of low cost, energy efficiency, and chemical stability. To date, mechanoresponsive smart windows are mainly built on periodic nano- or microstructures such as arrays, wrinkles, 3D photonic crystals, and polymeric nanocomposites. However, the production of periodic structures requires multiple and complicated processes, which restricts large-scale manufacturing of mechanoresponsive smart windows for practical application. Here, we report one-pot fabrication of poly methacrylic acid sodium salt (PMANa)/polyurethane (PU) mechanoresponsive smart windows with a nonperiodic naturally occurring microsized structure. The obtained smart windows display a high contrast ratio and stable transparency switching behavior under 80% tensile strain over 1000 cycles and have a large breaking elongation of 820%. It offers a promising platform for designing and fabricating multifunctional optical devices including anticounterfeiting labels and dynamical light gratings.

Plasmon-Enhanced Controlled Drug Release from Ag-PMA Capsules.

Silver (Ag)-grafted PMA (poly-methacrylic acid, sodium salt) nanocomposite loaded with sorafenib tosylate (SFT), an anticancer drug, showed good capability as a drug carrier allowing on-demand control of the dose, timing and duration of the drug release by laser irradiation stimuli. In this study, the preparation of Ag-PMA capsules loaded with SFT by using sacrificial silica microparticles as templates was reported. A high drug loading (DL%) of ∼13% and encapsulation efficiency (EE%) of about 76% were obtained. The photo-release profiles were regulated via the adjustment of light wavelength and power intensity. A significant improvement of SFT release (14% vs. 21%) by comparing SFT-Ag-PMA capsules with Ag-PMA colloids under the same experimental conditions was observed. Moreover, an increase of drug release by up to 35% was reached by tuning the laser irradiation wavelength near to Ag nanoparticles’ surface plasmon resonance (SPR). These experimental results together with more economical use of the active component suggest the potentiality of SFT-Ag-PMA capsules as a smart drug delivery system.

Controlled bi-functionalization of silica microbeads through grafting of amidoxime/methacrylic acid for Sr(II) enhanced sorption

Silica microspheres are functionalized through the grafting of either polymethacrylic acid or amidoxime groups (mono-functional composite, PMAA/SiO2 and PAO/SiO2, respectively) or in combination (bi-functional composite, PAOxMAA100-x/SiO2). The materials are characterized by textural analysis, TGA, SEM-EDX, elemental analysis, FTIR, XPS, pHPZC in order to confirm the synthesis route, identify the reactive groups and support the interpretation of sorption mechanisms toward Sr(II). The sorption of Sr(II), at optimum pH 8, involves amine groups and hydroxyl/carboxyl groups in the bi-functional composite sorbent. The comparison of sorption properties shows that maximum sorption requires a majority of carboxylic groups from polyacrylic compared with amidoxime functions; optimum formulation: PAO20MAA80/SiO2 sorbent. Sorption isotherms are efficiently fitted by the Langmuir and Sips equations: the maximum sorption capacity reaches around 1.38 mmol Sr g−1. Kinetic profiles for sorption are modeled using the pseudo-first order rate equation; equilibrium is achieved within 40–60 min. Complete desorption of Sr(II) using 1 M HCl solutions is even faster; equilibrium time being 15–20 min. The sorbent can be recycled for 5 cycles with a limited decrease in the sorption performance, and full desorption. In fixed-bed column, the breakthrough curves are fitted by the Thomas equation. In multi-component solutions, the sorbent shows a preferred selectivity according the sequence: K(I) > Ba(II) > Na(I) > Ca(II). Tested on seawater, the sorbent shows high distribution ratio for Sr(II), B(III) and Mo(VI)

Structure and Properties of Coatings Based on Acrylic-Containing Coordination Metal Complexes

A number of coordination metal complexes based on cards and linear oligoarylenamines as ligands with cobalt(II) nitrate in a solution of dimethylformamide were synthesized. To improve conductive and adhesive characteristics, the obtained complexes were reacted with polymethacrylic acid and a copolymer of methacrylic acid with methyl methacrylate. It is shown that the obtained materials have a range of properties inherent in coordination metal complexes, but with improved adhesive characteristics.

Heterogeneous Functionalization of Polyethersulfone: A New Approach for pH-Responsive Microfiltration Membranes with Enhanced Antifouling Properties

In this work, 2,2’-azo-bis-butyronitrile (AIBN) was exploited as an initiator for the successful bulk heterogeneous functionalization of polyethersulfone (PES) using polymethacrylic acid (PMAA), for the first time. To this end, pH-responsive and exceptionally low fouling membranes of extremely low grafting degrees with low adhesion and high rejection of protein were fabricated. An added advantage of this method is the accomplishment of graft polymerization of methacrylic acid (MAA) in water in the absence of toxic solvents, scavengers or catalysts. Changes to surface functional groups of the PES powder were determined using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and thereafter validated with X-ray photoelectron spectroscopy (XPS). The phase inversion technique was used to fabricate microfiltration membranes (MFs), which were found to possess up to 40% improved hydrophilicity relative to pristine PES membranes. Protein adsorption was reduced by more than 80% while its rejection and the pure water permeate flux recovery ratio (FR) were 97%, and 86%, respectively. Furthermore, the membrane maintained 90% FR over 10 cycles. The newly fabricated membranes possess enhanced response to pH stimulus.

Structure and nanomechanical characterization of synthetic calcium-silicate-hydrate with poly-methacrylic acid

ABSTRACT: The principal phase of hardened Portland cement pastes is calcium silicate hydrate (C-S-H), which influences the physical and mechanical properties of construction materials. In this work, calcium silicate hydrate (C-S-H) was synthesized, with the addition of poly-methacrylic acid with sodium (PMA), for the development of C-S-H/ polymer nanocomposites. Among the polymers available, PMA is indicated in the literature as one of those viable for producing C-S-H/polymer complexes. However, no consensus exists regarding the type of interaction this produces. The resulting compounds were characterized by XRD, FT-IR, TGA, carbon content (CHN), TEM, SEM and elastic modulus and hardness were measured by instrumented indentation. A significant change was verified in the nanomechanical properties of C-S-H with PMA, resulting in reduction in the elastic modulus and hardness. The set of results presented do not confirm the intercalation of PMA in the interlayer space of C-S-H, but presented evidence of the potential for intercalation, since changes in the microstructure clearly occurred.

Optical and Morphological Characteristics of Polymer Molecular Brushes with Varied Grafting Density and Binary Bioactive Radachlorine-Containing Nanosystems Based on Them

The optical and morphological characteristics of polymer molecular brushes with the polyimide backbone and polymethacrylic acid side chains, and also of binary nanosystems based on the molecular brushes and Radachlorine®, a photosensitizer of second generation, were studied. The brushes had the same backbone and approximately equal molecular mass of side chains, but strongly differed in the side chain grafting density. The side chain grafting density influences the molecular-conformation and morphological parameters of free molecular brushes and of the corresponding binary nanosystems.

Phenomenon of Remote Interaction and Sorption Ability of Rare Cross-linked Hydrogels of Polymethacrylic Acid and Poly-4-vinylpyridine in Relation to Erbium Ions

Досліджено вплив гідрогелю поліметакрилової кислоти–полі-4-вінілпіридину (інтергелева система gPMAA–gP4VP) на сорбцію йонів ербію. Встановлено, що структура основного гідрогелю має значний вплив на самоорганізацію гідрогелю PMAA. Взаємну активацію гідрогелів досліджено у водному середовищі. Встановлено залежності коефіцієнта набухання, питомої електропровідності та рН водних розчинів. Визначено, що ступінь екстракції йонів ербію для PMAA і P4VP становлять 44 % і 17 %, відповідно. Показано, що при співвідношеннях 5:1 (83 % gPMAA–17 % gP4VP) і 4:2 (67 % gMPAA–33 % gP4VP), були відновлені 56 % і 53 % йонів ербію відповідно. Через 48 год гідрогелі PMAA і P4VP мали ступінь зв'язування полімерного ланцюга 70 %. Спостерігались значні зміни в електрохімічних і конформаційних ступенях початкових макромолекул в інтергелевій системі gPMAA–gP4VP.

Complexes of Amphiphilic Molecular Brushes with a Polyimide Backbone with Poly-N-Vinylamides in Selective Solvents

The interaction of a molecular brush consisting of a polyimide backbone and luminescence-labeled poly(methacrylic acid) side chains with poly-N-vinylamides (poly-N-vinylpyrrolidone and poly-N-vinylcaprolactam) with different molecular weights is studied via polarized luminescence under stationary excitation in organic solvents with different thermodynamic qualities in relation to the chain blocks of the polymers, namely, selective (methanol) and common (dimethylformamide). The decrease in the mobility of the grafted poly(methacrylic acid) chains with the growth in the molecular weight of poly-N-vinylamide observed in both selective and common solvents gives evidence of the transition from a “loose” structure to a more compact structure of the interpolymer complex. It is shown on the basis of the analysis of the nanosecond relaxation times characterizing the mobility of the sections of the grafted poly(methacrylic acid) chains and reflecting the change in the intra- and intermolecular interactions that the formation of interpolymer complexes in dimethylformamide leads to a looser structure.

Evaluation of gypsum (CaSO4·2H2O) scale formation and its inhibition by different antiscalants by static and dynamic test

ABSTRACT Deposition of calcium salts or scaling on heat transfer surfaces is a major industrial problem around the globe. Scales get deposited in industrial process equipments severely affecting its life span, operating cost and adversely altering the process. Antiscalants are widely used for inhibition of metal salts formed in this water. In this study, chemical species like phosphates, various vinyl monomers and polymethacrylic acid are tested for their scale inhibition properties under static condition as per NACE standard and dynamic condition using SS and MS metal Strips. The performance of the compounds like Acrylic Acid, Malic acid, Succinic Acid and Polymethacrylic acid, studied during this working was found to be increasing with an increase in the number of a carboxylic (-COOH) group attached to its molecule. The presence of a negative charge over the carboxyl group plays an important role in the formation of ionic bond with the Ca2+ ions present in the liquid bulk. The carboxyl group attaches itself on the active sites of the crystal lattice and changes the crystal morphology significantly by blocking the active sites for its possible future growth.

Synthesis of IONP's decorated graft copolymers and study of their magnetic force–induced wastewater treatment

Our work is focused on facile synthesis and modification of amylopectin‐grafted block copolymers by using reversible addition−fragmentation chain transfer (RAFT) polymerization technique. This technique yields polymers with controlled molecular weight and low polydispersity indexes and is feasible with a wide range of monomers. Five different grades of amylopectin‐grafted polymethacrylic acid and polyacrylamide block copolymers have been synthesized via RAFT, by varying the amount of acrylamide employing amylopectin‐based macro chain transfer agent. Graft copolymers have been upgraded as smart responsive graft copolymers, through the incorporation of iron oxide nanoparticles (IONPs) via condensation reaction. The polymeric materials have been extensively characterized by energy‐dispersive X‐ray analysis, Fourier transform infrared spectroscopy, proton magnetic resonance spectroscopy, scanning electron microscopy, ultraviolet‐visible spectroscopy, gel permeation chromatography, transmission electron microscopy, thermogravimetric analysis, and X‐ray diffraction analysis. Normal and responsive graft copolymers have been studied for removal of model contaminant (kaolin), and responsive graft copolymers have been used to remove methylene blue dye (without using any adsorbent) from water by applying external magnetic field. The upgraded block copolymers have shown best performance in wastewater treatment.

Polymethacrylic Acid Shows Thermoresponsivity in an Organic Solvent

The alternating sequenced copolymer poly-(methacrylic acid-alt-hydroxyethyl acrylate), p(MAA-alt-HEA), was recently found to display a lower critical solution temperature (LCST) behavior in 1,2-dim...

An ingenious molecularly imprinted photo-induced sensor for ultrasensitive determination of sulfadiazine based on the urchin-shaped Bi2S3

An ingeniously conceived molecularly imprinted photo-induced sensor with polymethacrylic acid (PMAA) embedded into the urchin-shaped Bi2S3 architecture was devised, which was dedicated to sensitive exploring the sulfadiazine (SDZ). One critical procedure is the identification of PMAA and SDZ molecules by hydrogen bonding, and creates copious particular recognition sites upon the elution of SDZ molecules. It is worth mentioning that urchin-shaped Bi2S3 of cuboid nanorods compact stacked can provide a large specific surface area and enable more SDZ molecularly imprinted polymers to be attached or embedded in it. Accordingly, when encountering SDZ molecules again, a sensitive augment of photocurrent signal is captured, which reveals outstanding linear relationship in the concentration domain 0.003–1.8 mg L−1 and the detection limit is calculated to be 9.06 × 10−8 g L−1 (S/N = 3). Moreover, it is gratifying that as-prepared photo-induced sensor exhibits marked selectivity for the analysis of SDZ when exposed certain interfering species with similar configurations. Considerable reproducibility and stability in conjunction with tap water and aquatic water as actual samples of the fabricated photo-induced sensor are further evaluated, corroborating the prominent photoelectrochemical performances. The integrated photo-induced with molecularly imprinted approach will be utilized to probe into these vast unexplored environmental contaminants in this specific, effective and rapid detection manner.