3-sulfopropyl Methacrylate Potassium Research Articles

PH-Responsive Nanogels Generated by Polymerization-Induced Self-Assembly of a Succinate-Functional Monomer.

Colloidal nanogels formed from a pH-responsive poly(succinate)-functional core and a poly(sulfonate)-functional corona were prepared via a previously unreported reversible addition-fragmentation chain-transfer (RAFT)-mediated aqueous emulsion polymerization-induced self-assembly (PISA) route. Specifically, a poly(potassium 3-sulfopropyl methacrylate) (PKSPMA50) macromolecular chain-transfer agent (macro-CTA) was synthesized via RAFT solution polymerization followed by chain-extension with a hydrophobic, carboxylic acid-functional, 2-(methacryloyloxy) ethyl succinate (MES) monomer at pH 2. Colloidal nanoparticles with tunable diameters between 66 to 150 nm, depending on the core composition, and narrow particle size distributions were obtained at 20% w/w solids. Well-defined pH-responsive nanogels that swell on increasing the pH could be prepared even without the addition of a cross-linking comonomer, and introducing an additional cross-linker to the core led to smaller nanogels with lower swelling ratios. These nanogels could reversibly change in size on cycling the pH between acidic and basic conditions and remain colloidally stable over a wide pH range and at 70 °C.

Adsorption equilibrium and kinetics studies of crystal violet adsorbed by anionic polymer brush functionalized mesoporous silica nanoparticles

The removal of crystal violet (CV) dye from an aqueous solution has been investigated using anionic poly(potassium 3-sulfopropyl methacrylate) (PKSPMA) brushes grafted on mesoporous silica nanoparticles (MSNPs). Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) were used to characterize PKSPMA brushes modified MSNPs (PKSPMA@MSNPs). Surface-modified MSNPs were almost spherical shapes with sizes ranging between 190 nm and 340 nm with an average pore size of ca. 5. The adsorption process of the CV was investigated under various of testing conditions, including pH, contact duration and initial dye concentration. The maximum loading of CV onto PKSPMA@MSNPs was observed at pH 3, with approximately 91% adsorption efficiency at a concentration of 100 ppm. The removal of CV onto PKSPMA@MSNPs was best described by the Langmuir isotherm, with a maximum monolayer adsorption capacity (qmax) of 128.37 mg g−1. The kinetics of the adsorption process were best described by the pseudo-second-order model.

Polymer Gel Substrate: Synthesis and Application in the Intensive Light Artificial Culture of Agricultural Plants.

This work is devoted to the description of the synthesis of hydrogels in the process of cryotropic gel formation based on copolymerization of synthesized potassium 3-sulfopropyl methacrylate and 2-hydroxyethyl methacrylate (SPMA-co-HEMA) and assessing the potential possibility of their use as substrates for growing plants in intensive light culture in a greenhouse. Gel substrates based on the SPMA-co-HEMA were created in two compositions, differing from each other in the presence of macro- and microelements, and their effects were studied on the plants' physiological state (content of chlorophylls a and b, activity of catalase and peroxidase enzymes, intensity of lipid peroxidation, elemental compositions) at the vegetative period of their development and on the plants' growth, productivity and quality of plant production at the final stages of development. Experiments were carried out under controlled microclimate conditions. Modern and standard generally accepted methods of gels were employed (ATR-FTIR and 13C NMR spectral studies, scanning electron microscopy, measurement of specific surface area and pore volume), as well as the methods of the physiological and chemical analysis of plants. The study demonstrated the swelling ability of the created gel substrates. Hydrogels' structure, their specific surface area, porosity, and pore volume were investigated. Using the example of representatives of leaf, fruit and root vegetable crops, the high biological activity of gel substrates was revealed throughout the vegetation period. Species specificity in the reaction of plants to the presence of gel substrates in the root-inhabited environment was revealed. Lettuce, tomato and cucumber plants were more responsive to the effect of the gel substrate, and radish plants were less responsive. At the same time, more pronounced positive changes in plant growth, quality and productivity were observed in cucumber and lettuce in the variant of gel substrates with macro- and microelements and in tomato plants in both variants of gel substrates. Further research into the mechanisms of the influence of gel substrates on plants, as well as the synthesis of new gel substrates with more pronounced properties to sorb and retain moisture is promising.

Physical Adsorption of Graphene Oxide onto Polymer Latexes and Characterization of the Resulting Nanocomposite Particles.

Polymer/graphene oxide (GO) nanocomposite particles were prepared via heteroflocculation between 140–220 nm cationic latex nanoparticles and anionic GO nanosheets in either acidic or basic conditions. It is demonstrated that nanocomposite particles can be formed using either poly(2-vinylpyridine)-b-poly(benzyl methacrylate) (P2VP–PBzMA) block copolymer nanoparticles prepared by reversible-addition chain-transfer (RAFT)-mediated polymerization-induced self-assembly (PISA), or poly(ethylene glycol)methacrylate (PEGMA)-stabilized P2VP latexes prepared by traditional emulsion polymerization. These two latexes are different morphologically as the P2VP–PBzMA block copolymer latexes have P2VP steric stabilizer chains in their corona, whereas the PEGMA-stabilized P2VP particles have a P2VP core and a nonionic steric stabilizer. Nevertheless, both the P2VP–PBzMA and PEGMA-stabilized P2VP latexes are cationic at low pH. Thus, the addition of GO to these latexes causes flocculation to occur immediately due to the opposite charges between the anionic GO nanosheets and cationic latexes. Control heteroflocculation experiments were conducted using anionic sterically stabilized poly(potassium 3-sulfopropyl methacrylate)-b-poly(benzyl methacrylate) (PKSPMA–PBzMA) and nonionic poly(benzyl methacrylate) (PBzMA) nanoparticles to demonstrate that polymer/GO nanocomposite particles were not formed. The degree of flocculation and the strength of electrostatic interaction between the cationic polymer latexes and GO were assessed using disc centrifuge photosedimentometry (DCP), transmission electron microscopy (TEM), and UV–visible spectrophotometry. These studies suggest that the optimal conditions for the formation of polymer/GO nanocomposite particles were GO contents between 10% and 20% w/w relative to latex, with the latexes containing P2VP in their corona having a stronger electrostatic attraction to the GO sheets.

Mitigating Early Phase Separation of Aliphatic Random Ionomers by the Hydrophobic H-Bond Acceptor Addition

This study reports a new phenomenon whereby the ionic content of a random ionomer was increased by the introduction of a hydrophobic modifier. In the current study, the ionomer synthesized from the solution polymerization of the three vinyl monomers, which are polar hydrophobic monomers acrylonitrile (AN), glycidyl methacrylate (GMA), and ionic monomer potassium 3-sulfopropyl methacrylate (SPM), encountered an early phase separation problem when the ionic content exceeded a certain threshold value. However, the addition of a strongly hydrophobic monomer, 2,2,3,3-tetrafluoropropyl methacrylate (TFPM), during the copolymerization is able to restrain this phase separation trend, consequently allowing 50% more of SPM units to be incorporated and uniformly distributed in the ionomer and achieving a random copolymer chain. The ionic clustering of the SPM units, which is the cause for the phase separation, was reduced as a result. The resulting random ionomer was demonstrated to be a superior proton conducting material over its ternary originator. This is due to the fact that TFPM possesses acidic protons, which brings about an association of TFPM with SPM and GMA via hydrogen bonding. This study could impact the synthesis of random ionomers by free radical polymerization since monitoring ionic content and improving ionic unit distribution in ionomers are issues encountered in several industries (e.g., the healthcare industry).

Digitally Driven Aerosol Jet Printing to Enable Customisable Neuronal Guidance.

Digitally driven manufacturing technologies such as aerosol jet printing (AJP) can make a significant contribution to enabling new capabilities in the field of tissue engineering disease modeling and drug screening. AJP is an emerging non-contact and mask-less printing process which has distinct advantages over other patterning technologies as it offers versatile, high-resolution, direct-write deposition of a variety of materials on planar and non-planar surfaces. This research demonstrates the ability of AJP to print digitally controlled patterns that influence neuronal guidance. These consist of patterned poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) tracks on both glass and poly(potassium 3-sulfopropyl methacrylate) (PKSPMA) coated glass surfaces, promoting selective adhesion of SH-SY5Y neuroblastoma cells. The cell attractive patterns had a maximum height ≥0.2 μm, width and half height ≥15 μm, Ra = 3.5 nm, and RMS = 4.1. The developed biocompatible PEDOT:PSS ink was shown to promote adhesion, growth and differentiation of SH-SY5Y neuronal cells. SH-SY5Y cells cultured directly onto these features exhibited increased nuclei and neuronal alignment on both substrates. In addition, the cell adhesion to the substrate was selective when cultured onto the PKSPMA surfaces resulting in a highly organized neural pattern. This demonstrated the ability to rapidly and flexibly realize intricate and accurate cell patterns by a computer controlled process.

PH-responsive nano-structured membranes prepared from oppositely charged block copolymer nanoparticles and iron oxide nanoparticles

Nanostructured (hybrid) membranes combining properties of inorganic and polymeric materials is an integral part of the field of separation technology. Mixed matrix membranes were prepared from oppositely charged inorganic (INPs) and polymeric (PNPs) nanoparticles using spin coating method. Four different types of PNPs were prepared. Poly(2-dimethylaminoethyl methacrylate)-b-(methyl methacrylate)) and poly((methacrylic acid)-b-(methyl methacrylate)) diblock copolymers were prepared via RAFT dispersion polymerization in ethanol at 70 °C. Quaternized poly(2-(dimethylamino) ethyl methacrylate)-b-poly (benzyl methacrylate) and poly(potassium 3-sulfopropyl methacrylate)-b-poly (benzyl methacrylate) block copolymers were prepared using aqueous RAFT emulsion polymerization method at 70 °C. The inorganic iron oxide nanoparticles (INPs) were either coated with [3-(2-Aminoethylamino)propyl] trimethoxysilane (TPED) via Dimercaptosuccinic acid (DMSA) using stab exchange. Transmission electron microscopy (TEM) and Dynamic light scattering (DLS) analysis were performed to examine the size and morphology of the prepared polymeric and inorganic nanoparticles. Scanning electron microscope (SEM) and Atomic Force Microscope (AFM) images were obtained to analyze the topography and thin film formation on the nylon support. Detailed filtration experiments were carried out to evaluate the effect of pH on the performance of the membrane.

Controlled Arrangement of Neuronal Cells on Surfaces Functionalized with Micropatterned Polymer Brushes.

Conventional in vitro cultures are useful to represent simplistic neuronal behavior; however, the lack of organization results in random neurite spreading. To overcome this problem, control over the directionality of SH-SY5Y cells was attained, utilizing photolithography to pattern the cell-repulsive anionic brush poly(potassium 3-sulfopropyl methacrylate) (PKSPMA) into tracks of 20, 40, 80, and 100 μm width. These data validate the use of PKSPMA brush coatings for a long-term culture of the SH-SY5Y cells, as well as providing a methodology by which the precise deposition of PKSPMA can be utilized to achieve a targeted control over the SH-SY5Y cells. Specifically, the PKSPMA brush patterns prevented cell attachment, allowing the SH-SY5Y cells to grow only on noncoated glass (gaps of 20, 50, 75, and 100 μm width) at different cell densities (5000, 10 000, and 15 000 cells/cm2). This research demonstrates the importance of achieving cell directionality in vitro, while these simplistic models could provide new platforms to study complex neuron–neuron interactions.

Layer-By-Layer Self-Assembly of Polyelectrolytic Block Copolymer Worms on a Planar Substrate.

Cationic and anionic block copolymer worms are prepared by polymerization-induced self-assembly via reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion copolymerization of 2-hydroxypropyl methacrylate and glycidyl methacrylate (GlyMA), using a binary mixture of a nonionic poly(ethylene oxide) macromolecular RAFT agent and either a cationic poly([2-(methacryloyloxy)ethyl]trimethylammonium chloride) or an anionic poly(potassium 3-sulfopropyl methacrylate) macromolecular RAFT agent. In each case, covalent stabilization of the worm cores was achieved via reaction of the epoxide groups on the GlyMA repeat units with 3-mercaptopropyltriethoxysilane. Aqueous electrophoresis studies indicated a pH-independent mean zeta potential of +40 mV and −39 mV for the cationic and anionic copolymer worms, respectively. These worms are expected to mimic the rigid rod behavior of water-soluble polyelectrolyte chains in the absence of added salt. The kinetics of adsorption of the cationic worms onto a planar anionic silicon wafer was examined at pH 5 and was found to be extremely fast at 1.0 w/w % copolymer concentration in the absence of added salt. Scanning electron microscopy (SEM) analysis indicated that a relatively constant worm surface coverage of 16% was achieved at 20 °C for adsorption times ranging from just 2 s up to 2 min. Furthermore, the successive layer-by-layer deposition of cationic and anionic copolymer worms onto planar surfaces was investigated using SEM, ellipsometry, and surface zeta potential measurements. These techniques confirmed that the deposition of oppositely charged worms resulted in a monotonic increase in the mean layer thickness, with a concomitant surface charge reversal occurring on addition of each new worm layer. Unexpectedly, two distinct linear regimes were observed when plotting the mean layer thickness against the total number of adsorbed worm layers, with a steeper gradient (corresponding to thicker layers) being observed after the deposition of six worm layers.

Anti-Bioadhesive Coating Based on Easy to Make Pseudozwitterionic RAFT Block Copolymers for Blood-Contacting Applications.

Amphiphilic diblock copolymer containing randomly distributed positive and negative charged monomers are synthesized using RAFT polymerization technique to be used as anti-bioadhesion coatings for hydrophobic surfaces. Quaternized 2-(dimethylamino) ethyl methacrylate and potassium 3-sulfopropyl methacrylate (P[qDMAEMA-co-KSPMA]) are randomly polymerized to yield an anti-bioadhesion block which is, in one pot, copolymerized with styrene as an anchoring block. This copolymer has demonstrated high anti-bioadhesion properties to avoid the blood clotting in medical devices through a simple and facile approach to preparation of pseudozwitterionic copolymers.

Anionic Polyelectrolyte-Stabilized Nanoparticles via RAFT Aqueous Dispersion Polymerization

We report the synthesis of anionic sterically stabilized diblock copolymer nanoparticles via polymerization-induced self-assembly using a RAFT aqueous dispersion polymerization formulation. The anionic steric stabilizer is a macromolecular chain-transfer agent (macro-CTA) based on poly(potassium 3-sulfopropyl methacrylate) (PKSPMA), and the hydrophobic core-forming block is based on poly(2-hydroxypropyl methacrylate) (PHPMA). The effect of varying synthesis parameters such as the salt concentration, solids content, relative block composition, and anionic charge density has been studied. In the absence of salt, self-assembly is problematic when using a PKSPMA stabilizer because of lateral repulsion between highly charged anionic chains. However, in the presence of added salt this problem can be overcome by reducing the charge density within the coronal stabilizer layer by either (i) statistically copolymerizing the KSPMA monomer with a nonionic comonomer (2-hydroxyethyl methacrylate, HEMA) or (ii) using a binary mixture of a PKSPMA macro-CTA and a poly(glycerol monomethacrylate) (PGMA) macro-CTA. These diblock copolymer nanoparticles were analyzed by (1)H NMR spectroscopy, gel permeation chromatography (GPC), dynamic light scattering (DLS), transmission electron microscopy (TEM), and aqueous electrophoresis. NMR studies suggest that the HPMA polymerization is complete within 2 h at 70 °C, and DMF GPC analysis confirms that the resulting diblock copolymers have relatively low polydispersities (M(w)/M(n) < 1.30). NMR also suggests a significant degree of hydration for the core-forming PHPMA chains. Depending on the specific reaction conditions, a series of spherical nanoparticles with mean diameters ranging from 50 to 200 nm with tunable anionic surface charge can be prepared. If a binary mixture of anionic and nonionic macro-CTAs is utilized, then it is also possible to access a vesicular morphology.

Charge- and temperature-dependent interactions between anionic poly(N-isopropylacrylamide) polymers in solution and a cationic surfactant at the water/air interface

Due to their expanded coil to collapsed globule transition close to physiological temperatures, N-isopropylacrylamide (NIPAAM) polymers and derivatives thereof represent promising drug delivery vectors. Here, we report on the interaction between anionic PNIPAAM derivatives containing potassium 3-sulfopropylmethacrylate (SPMA) blocks of various sizes and a cationic lipid membrane mimic as a function of temperature, polymer charge density and molecular weight, by injection under a pre-compressed surfactant monolayer. The resulting film properties (including equilibria) were studied using surface pressure–area isotherms, Brewster angle microscopy, and interfacial 2D oscillatory rheology. Whereas mixed films of dioctadecyldimethylammonium bromide (DODAB) and an uncharged PNIPAAM homopolymer resulted in distinct polymer and surfactant domains, the anionic polyelectrolytes were found to ionically cross-link and contract the DODAB film. Film penetration, charge screening and surfactant film contraction were dependent on the molecular weight and size of the SPMA blocks on the polymers.

Direct Synthesis of Poly(potassium 3-sulfopropyl methacrylate) Cylindrical Polymer Brushes via ATRP Using a Supramolecular Complex With Crown Ether

A supramolecular complex between an ionic monomer 3-sulfopropyl methacrylate (SPMAK) and crown ether 18-crown-6 (18C6) has been employed to prepare a strong anionic cylindrical polyelectrolyte brush poly(potassium 3-sulfopropyl methacrylate) (PSPMAK) by atom transfer radical polymerization (ATRP) in polar solvent dimethyl sulfoxide (DMSO). This strategy solved the problem of the solubilities of the incompatible hydrophobic poly-initiator and hydrophilic ionic monomer. The formation of the PSPMAK brush is well proven by (1) H NMR, aqueous gel permeation chromatography (GPC), dynamic light scattering (DLS), static light scattering (SLS), atomic force microscopy (AFM), and cryogenic transmission electron microscopy (cryo-TEM) measurements. Cleavage of the side chains and further analysis reveal that the initiating efficiency of the polymerization is as low as 0.35.

Facile Synthesis of Well-Defined Hydrophilic Methacrylic Macromonomers Using ATRP and Click Chemistry

A range of well-defined hydrophilic methacrylic macromonomers has been synthesized by the judicious combination of atom transfer radical polymerization (ATRP) and copper-catalyzed 1,3-dipolar cycloaddition (azide−alkyne click chemistry). An azido α-functionalized ATRP initiator was used to produce well-defined homopolymers with terminal azide functionality via ATRP in protic media at 20 °C, with generally good control being achieved over both target molecular weight and final polydispersity (Mw/Mn = 1.10−1.35). Suitable methacrylic monomers include 2-aminoethyl methacrylate hydrochloride, 2-(diethylamino)ethyl methacrylate, 2-(dimethylamino)ethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-(methacryloyloxy)ethyl phosphorylcholine, glycerol monomethacrylate, potassium 3-sulfopropyl methacrylate, and quaternized 2-(dimethylamino)ethyl methacrylate. These homopolymer precursors were then efficiently clicked using either propargyl methacrylate or propargyl acrylate to yield near-monodisperse (meth)acrylate-capped macromonomers with either cationic, anionic, nonionic, or zwitterionic character. Moreover, this generic route to well-defined hydrophilic macromonomers is also suitable for “one-pot” syntheses, as exemplified for 2-hydroxyethyl methacrylate and glycerol monomethacrylate-based macromonomers.

Atom Transfer Radical Polymerization of Potassium 3-Sulfopropyl Methacrylate: Direct Synthesis of Amphiphilic Block Copolymers with Methyl Methacrylate

The synthesis of potassium 3-sulfopropyl methacrylate (SPMA) homopolymers and amphiphilic block copolymers with methyl methacrylate (MMA) by ATRP in water/DMF mixed solvent at 20 °C using a Cu/bipyridine catalyst and halogen exchange is described. SPMA homopolymerization in pure water was poorly controlled even when 200% of Cu(II)Cl2 with respect to Cu(I)Cl was added, leading to a relatively high polydispersity (1.38). In water:DMF 50:50 (v/v), addition of at least 60% of Cu(II)Cl2 with respect to Cu(I)Cl allowed to obtain a good control of the polymerization. Linear kinetic plots up to very high conversion were observed and the final polydispersities were relatively low (1.15−1.25). Good self-blocking efficiencies were demonstrated by chain extension experiments even when the first block conversion before the addition of the second feed was very high (>90%). Amphiphilic block copolymers with MMA (number-average degree of polymerization Xn,SPMA = 50, Xn,MMA = 25) were directly prepared in water:DMF 40:60 (v/v) without using protecting group chemistry or post-polymerization derivatization. The first-order kinetic plot for MMA polymerization was linear up to 96% conversion. Two block copolymers with the same composition, p(SPMA50-b-MMA25)1pot and p(SPMA50-b-MMA25)2pot, were prepared with “one-pot” and “two-pot” procedures. p(SPMA50-b-MMA25)2pot prepared using a purified pSPMA macroinitiator for MMA polymerization gave well-defined core−shell spherical micelles with an average hydrodynamic radius of about 14 nm determined by dynamic light scattering (DLS) measurements. p(SPMA50-b-MMA25)1pot prepared using the sequential monomer addition gave large micellar clusters (more than 100 nm) in addition to simple but smaller micelles. A tentative explanation to the presence of the larger aggregates was given.

X-ray Photoelectron Spectroscopy Studies on Sterically-Stabilized Polypyrrole Particles

The surface composition of a sterically-stabilized polypyrrole colloid has been examined by X-ray photoelectron spectroscopy (XPS). The sulfur atom of the polyelectrolyte stabilizer poly(potassium 3-sulfopropyl methacrylate) [PKSPM] and the nitrogen atom of the polypyrrole were used as unique elemental markers for each component. The S/N atomic ratio at the particle surface determined using XPS was found to be significantly higher than the corresponding ‘macroscopic' S/N atomic ratio calculated from elemental microanalyses. This is the first direct evidence for the presence of a stabilizer-rich layer at the surface of sterically-stabilized conducting polymer particles. Changing to a lower energy X-ray source (Mg Kα) did not lead to an increase in the surface S/N ratio; thus, the stabilizer layer is probably ‘patchy' rather than a continuous coating. XPS also revealed that the surface concentrations of the K+ and Cl- counterions in the colloid were substantially depleted relative to those found in the PKSPM stabilizer and chloride-doped polypyrrole ‘bulk powder'. Moreover, the surface dopant level of the polypyrrole particles calculated on the basis of the remaining chloride ions was unusually low (Cl/N = 0.07). More realistic surface dopant levels were obtained if it was assumed that some of the sulfonate groups of the polyelectrolyte stabilizer acted as dopant anions for the conducting polymer component. It was concluded that the PKSPM stabilizer is adsorbed onto the surface of the polypyrrole particles as a polymeric dopant anion, with the concomitant expulsion of KCl. Finally, there is some evidence that this stabilizer is present as a polymeric dopant in the interior of the particles as well.

Modification of the dynamic swelling behavior of poly(2‐hydroxyethyl methacrylate) in water

AbstractThe equilibrium and dynamic swelling behavior of glassy polymers immersed in solvents can be modified by controlling the history of the polymer sample, which includes prior swelling and the drying method, or by copolymerization with other monomers. In this paper, the swelling kinetics in water of ionic hydrogels of 2‐hydroxyethyl methacrylate copolymerized with potassium 3‐sulfopropylmethacrylate and/or ethylene glycol dimethacrylate have been studied at 23°C. The dimensional changes of a swelling polymer sheet can be controlled through incorporation of anisotropic stresses in the initially dry, glassy polymer. These anisotropic stresses do not affect the swelling kinetics as long as the sample is partially glassy. However, differences in the initial stresses cause sharply different swelling kinetics once the polymer becomes entirely rubbery, due to differences in dimensional changes. Increasing the percentage of ionic comonomer in the polymer increases the equilibrium degree of swelling and the water sorption rate without changing the time for equilibration or the swelling transport mechanism. In contrast, increasing the percentage of cross‐linker in the polymer not only reduces the degree of swelling and water sorption rate, but also increases the equilibration time and shifts the water transport mechanism from Fickian diffusion to anomalous transport.