Methacryloyloxy Ethyl Succinate 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.

Quantum Dot Transfer from the Organic Phase to Acrylic Monomers for the Controlled Integration of Single-Photon Sources by Photopolymerization

This paper reports on a new strategy for obtaining homogeneous dispersion of grafted quantum dots (QDs) in a photopolymer matrix and their use for the integration of single-photon sources by two-photon polymerization (TPP) with nanoscale precision. The method is based on phase transfer of QDs from organic solvents to an acrylic matrix. The detailed protocol is described, and the corresponding mechanism is investigated and revealed. The phase transfer is done by ligand exchange through the introduction of mono-2-(methacryloyloxy) ethyl succinate (MES) that replaces oleic acid (OA). Infrared (IR) measurements show the replacement of OA on the QD surface by MES after ligand exchange. This allows QDs to move from the hexane phase to the pentaerythritol triacrylate (PETA) phase. The QDs that are homogeneously dispersed in the photopolymer without any clusterization do not show any significant broadening in their photoluminescence spectra even after more than 3 years. The ability of the hybrid photopolymer to create micro- and nanostructures by two-photon polymerization is demonstrated. The homogeneity of emission from 2D and 3D microstructures is confirmed by confocal photoluminescence microscopy. The fabrication and integration of a single-photon source in a spatially controlled manner by TPP is achieved and confirmed by auto-correlation measurements.

Fabrication of surface plasmon resonance sensor surface with control of the non-specific adsorption and affinity for the detection of 2,4,6-trinitrotoluene using an antifouling copolymer.

We fabricated a surface plasmon resonance (SPR) sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT). The hydrophilic polymer was made from mono-2-(methacryloyloxy)ethylsuccinate (MES) and 2-hydroxyethylmethacrylate (HEMA) by surface-initiated atom transfer radical polymerization. The detection of TNT was carried out by displacement assay with the SPR measurement. In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity. In the SPR measurement, non-specific adsorption should be controlled because SPR sensor cannot discriminate between specific and non-specific adsorption. Therefore, the affinity and non-specific adsorption were controlled by changing the ratio of HEMA to MES. A detection limit of 0.4 ng/ml (ppb) for TNT was achieved using a sensor surface with the lowest affinity without non-specific adsorption.

Fabrication of an SPR Sensor Surface with Antifouling Properties for Highly Sensitive Detection of 2,4,6-Trinitrotoluene Using Surface-Initiated Atom Transfer Polymerization

In this study, we modified a surface plasmon resonance immunosensor chip with a polymer using surface-initiated atom transfer polymerization (SI-ATRP) for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT). To immobilize a TNT analogue on the polymer, mono-2-(methacryloyloxy)ethylsuccinate (MES), which has a carboxyl group, was used in this study. However, the anti-TNT antibody may adsorb non-specifically on the polymer surface by an electrostatic interaction because MES is negatively charged. Therefore, a mixed monomer with MES and diethylaminoethylmethacrylate (DEAEM), which has a tertiary amino group and is positively charged, was prepared to obtain electroneutrality for suppressing the nonspecific adsorption. The detection of TNT was performed by inhibition assay using the polymer surface. To ensure high sensitivity to TNT, the affinity between the surface and the antibody was optimized by controlling the density of the initiator for ATRP by mixing two types of self-assembled monolayer reagents. As a result, a limit of detection of 5.7 pg/mL (ppt) for TNT was achieved using the optimized surface.

Preparation of stimuli-responsive hydrogel networks with threaded β-cyclodextrin end-capped chains via combination of controlled radical polymerization and click chemistry

Hydrogel networks of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-b-PPG-b-PEG primary network), with threaded sliding β-cyclodextrin-capped poly(2-(methacryloyloxy)ethyl succinate) (βCD-capped-PMES) chains, are described. The hydrogels were prepared by UV-initiated thiol–ene click reaction of the PEG-b-PPG-b-PEG diacrylate polymer with a crosslink agent, pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), in the presence of βCD end-capped chains, βCD-capped-PMES. The latter was prepared a priori by reversible addition–fragmentation chain transfer (RAFT) polymerization. Due to the controlled character of RAFT polymerization and the quantitative yield of thiol–ene click reaction, the as-synthesized PEG-b-PPG-b-PEG-thread-βCD-capped-PMES hydrogels have a well-defined PEG-b-PPG-b-PEG network and tunable PMES chain length. The length of PMES chains can be regulated by varying the molar ratio of 2-(methacryloyloxy)ethyl succinate (MES) monomer to RAFT agent. The molecular structures and thermal properties of the PEG-b-PPG-b-PEG-thread-βCD-capped-PMES hydrogels were studied by 1H NMR, XPS, TGA and DSC measurements. The polymer hydrogels with threaded sliding rings exhibit both pH- and temperature-dependent equilibrium swelling ratios in aqueous media and have potential applications as biomaterials and biomedical materials.

The role of methacrylate polymerized as porous‐layered and nanoparticle‐bound phases for open‐tubular capillary electrochromatography: Substitution of a charged monomer for a bulk monomer

The bulk monomer, butyl methacrylate (BMA), was copolymerized with an ionizable monomer (mono-(2-(methacryloyloxy)ethyl) succinate (MES)) and carbon nanotubes (CNTs) by ethylene dimethacrylate (EDMA) crosslinking to form the porous-layered and nanoparticle-bound stationary phases for open-tubular CEC. Here, two new phases were synthesized to check the role of BMA on the BMA-MES and BMA-CNT phases and the suitability of the MES monomer for concurrently acting as a bulk monomer. One phase, MES-EDMA, was simply composed of MES monomer and EDMA crosslinker and exhibited a phase construction of molecular layers, in contrast to the polymeric phases of BMA-MES. Another phase studied was MES-CNT, which SEM images showed that MES could be a good bulk monomer for a CNT-polyacrylate composite phase with embedded CNTs. For all the modified capillaries, the EOF profiles observed in phosphate buffers between pH 3.6 and 9.6 were comparable with each other and conformed to their corresponding SEM images. The residual silanols retained their influence on the EOF profiles in the MES-EDMA and BMA-MES capillaries, but diminished in the CNT-bound capillaries. In a comparison with the MES-EDMA capillary, the BMA-MES capillary afforded a stronger interaction with flavonoids and phenolic acids and still retained positive capacity factor values. Additionally, the capacity factors obtained from the BMA-CNT capillary were higher than those from the MES-CNT capillary, as the BMA-CNT phase had hydrophobic BMA units and a high surface contact area of bound CNTs.

Succinyl methacrylate polymerized in porous-layered phases for open-tubular capillary electrochromatography: Comparison with silica hydride monolayered phases

A polymer phase, which was constructed with butyl methacrylate (BMA), an ionizable monomer (mono-(2-(methacryloyloxy)ethyl) succinate (MES)), and a crosslinking agent (ethylene dimethacrylate), was first formed in a porous-layered open-tubular (PLOT) capillary. The PLOT capillary was characterized with SEM and electrophoretic flow as the pH level, ionic strength and addition of organic modifiers in the running buffers changed. In addition, a bare capillary and a silica hydride based capillary (SiH-MES), which bore a monolayered MES phase on it, were used to compared with the BMA-MES capillary. Besides optimizing the capillary electrochromatographic (CEC) conditions for each group of analytes, which were a mixture of nucleosides and thymine, flavonoids, and phenolic acids,comparison of the separation selectivity among analytes between the BMA-MES and SiH-MES capillaries was done according to the velocity and retention factors obtained from the CEC data. Overall, the polymeric phase formed in the PLOT mode was capable of preventing blockage of the columns and was superior to the monolayered phase bonding with the same ionizable ligands for application in CEC as well as to the bare silica phase in CE.

Comparision of succinate- and phthalate-functionalized etched silica hydride phases for open-tubular capillary electrochromatography

Two open-tubular (OT) capillary electrochromatographic (CEC) columns were prepared by chemically bonding ionizable mono-(2-(methacryloyloxy)ethyl) succinate (MES) and phthalate-functionalized (MEP) ligands onto silica hydride-based phases through surface etching, silanization, and hydrosilation reactions, starting with a bare fused-silica tube. An analysis of the effect of performance of electrophoretic flow (EOF) on the changes in pH values, ionic strength, and the amount of acetonitrile modifiers helped to reveal that some silanol groups remained in the surface composite of the modified capillaries and to prove that MEP capillaries actually exerted greater EOF than MES ones. To explore the potential utilization of these two columns in various fields, three categories of samples, which spanned a wide range of polarities, were prepared and analyzed through many systematic trials of optimizing CEC conditions. For the separation of a mixture of nucleosides and thymine, guanine and adenine with purine uncleobases, which exhibit greater aromaticity than pyrimidine nucleobases, performed a higher retention in the MEP capillary through a π–π interaction than in the MES capillary. While four steroids were used as test samples, their migration order revealed that the MES stationary phase is hydrophilic in comparison with the MEP. An addition of methanol modifier (30%, v/v) into 10 mM borate buffer (pH 9.55 for MEP; pH 10.0 for MES) was necessary to accomplish a baseline separation of nine flavonoids in the MEP and MES capillaries. Studies on the elution order of these solutes revealed the presence of chromatographic activity in addition to electrophoretic migration. Especially in the MEP capillary, hydrophobic characteristics and π–π interactions with aromatic solutes were found and further improved to resolve an enantiomeric pair, catechin and epicatechin. Overall, the hydride-based stationary phases with ionizable ligands were successfully applied to the OT-CEC separations, and these results confidently propose an ideal route to the synthesis of a novel OT-CEC column.

Rapid Synthesis of Functional Polymer Brushes by Surface-Initiated Atom Transfer Radical Polymerization of an Acidic Monomer

The combination of a highly reactive monomer, 2-(methacryloyloxy)ethyl succinate (MES), and active catalyst systems, e.g., Cu(I) complexed with 1,1,4,7,10,10-hexamethyltriethylenetetramine (HMTETA), allows rapid formation of poly(carboxylic acid) brushes by atom transfer radical polymerization (ATRP) from a surface. ATRP from initiators immobilized on Au-coated Si wafers yields films with an ellipsometric thickness of 120 nm in less than 15 min. To the best of our knowledge, this is the first example of direct ATRP of protonated acidic monomers that is capable of yielding such thick films, and MES polymerizes much more rapidly than methacrylic acid both in solution and on a surface. The MES films are attractive for a number of applications, including immobilization of proteins. Assuming that a lysozyme monolayer has a thickness of 2 nm, a 55 nm poly(MES) brush binds ∼70 monolayers of lysozyme via ion-exchange interactions. Additionally, when derivatized with nitrilotriacetate−Cu2+ complexes, poly(MES) films bind ∼34 monolayers of BSA through metal-ion affinity interactions (assuming a BSA monolayer thickness of 4 nm). These binding capacities are similar to those of poly(acrylic acid) brushes prepared by polymerization of tert-butyl acrylate and subsequent hydrolysis, but the poly(MES) synthesis is a one-step, aqueous process.

Effect of copper salts added to primer on bonding of MMA-TBB resin to dentin treated with phosphoric acid.

The effects of addition of various copper salts to 2-hydroxyethyl methacrylate (HEMA) primer were studied with regard to tensile bond strength of methyl methacrylate-tributylborane (MMA-TBB) resin to dentin. Bovine dentin surfaces were treated with 10% phosphoric acid, then with a primer consisting of aqueous 35% HEMA and a copper salt, and finally bonded to acrylic rods with MMA-TBB resin. The types of copper salts and concentrations in the primers were varied. The optimal concentration of copper salts in the primers was 0.5-3 mumol/g. The primers containing copper salts of sulfate, methacrylate, methacryloyloxyethyl phthalate, or methacryloyloxyethyl succinate were especially effective among the eight copper salts studied in increasing bond strength, producing mean bond strengths of 14.2-16.1 MPa and mean minimum values of 9.9-11.7 MPa. These bond strengths were higher than those obtained with the commercial 4-META/MMA-TBB resin system. A model experimental study concerning the molecular weight of poly (MMA) formed in the presence of some copper salts suggested that the increase in bond strength was produced through an increase in molecular weight of MMA-TBB resin by the copper salts.