Facile and fast synthesis of polyaniline-coated poly(glycidyl methacrylate) core–shell microspheres and their electro-responsive characteristics

Preparation and Boron Removal Performance of Glycidol Modified PANI Nanorods: An Optimization Study Based on Response Surface Methodology

Boron removal from aqueous solutions has attracted increasing attention, offering benefits for animal and plant health as well as profound significance for exploiting Salt Lake boron resources. In this work, we synthesized novel glycidol-functionalized and hydrophilic polyaniline (PANI) nanorod adsorbents, which were prepared to separate boron compounds from boric acid aqueous solutions. The as-prepared adsorbents were significantly different from the traditional polymers' grafting reaction because they had a higher functional yield and more active position for adsorption. The maximum adsorption capacity (0.2210 mmoL∙g^-1) and optimal adsorption conditions (boric acid concentration of 1307 mg/L, pH = 9.82, time of 10 h) were obtained with single-factor experimentation and the response surface method (RSM). In addition, adsorption kinetics studies showed that the adsorption reaction belonged to the pseudo-first-order kinetic model, and diffusion was the key limiting factor; therefore, the adsorption equilibrium time is more than 10 h. Finally, the related possible adsorption mechanism was investigated based on the species and the diffusion of boron in the aqueous phase.

Microporous poly(glycidyl methacrylate-co-ethylene glycol dimethyl acrylate) microspheres: synthesis, functionalization and applications

As a new kind of functional material, micron-sized porous polymer microspheres are a hot research topic in the field of polymer materials.

Polymer Brush-Induced Hollow Colloids via Diffusion-Controlled Silication

We report on a new strategy to synthesize asymmetrical hollow colloidal particles by exploiting limited chemical diffusion that occurs at the periphery of a solvated polymer brush on the particle surface. The polymer brush-in our case poly(glycidyl methacrylate)-bears hydroxyl groups upon hydrolysis and is partially cross-linked under the Stöber condition of silication. Desolvation of the polymers creates a cavity. While elucidating this new mechanism, we demonstrate that particles with various types of cavities and tunable properties can be synthesized, including the ones bearing hemispherical and crescent shapes, as well as particles with wrinkled surfaces. Furthermore, we show that the hollow particles adopt preferred orientations because of their shape and composition attributes, which is further explored to facilitate the confined synthesis of nanocrystals.

Nanoparticles Functionalized by Conducting Polymers and Their Electrorheological and Magnetorheological Applications

Conducting polymer-coated nanoparticles used in electrorheological (ER) and magnetorheological (MR) fluids are reviewed along with their fabrication methods, morphologies, thermal properties, sedimentation stabilities, dielectric properties, and ER and MR characteristics under applied electric or magnetic fields. After functionalization of the conducting polymers, the nanoparticles exhibited properties suitable for use as ER materials, and materials in which magnetic particles are used as a core could also be applied as MR materials. The conducting polymers covered in this study included polyaniline and its derivatives, poly(3,4-ethylenedioxythiophene), poly(3-octylthiophene), polypyrrole, and poly(diphenylamine). The modified nanoparticles included polystyrene, poly(methyl methacrylate), silica, titanium dioxide, maghemite, magnetite, and nanoclay. This article reviews many core-shell structured conducting polymer-coated nanoparticles used in ER and MR fluids and is expected to contribute to the understanding and development of ER and MR materials.

Fabrication and excellent electroresponsive properties of ideal PMMA@BaTiO3 composite particles

A series of core–shell-structured poly(methylmethacrylate)@BaTiO₃ (PMMA@BT) composite particles were constructed via the self-assembly of BT nanoparticles on the surfaces of PMMA cores through the covalent bonding of siloxane groups at room temperature. The PMMA@BT composite particles were characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction, video-based optical contact angle measurement, thermogravimetric analysis, and impedance analysis. The electroresponses of the obtained PMMA@BT composite particles were all stronger than that of pure BT, and the electroresponse depended on the weight percentage of the BT shell. The PMMA@BT particles with the optimal core–shell structure contained 58.14 wt% of BT shell. The surface hydrophilicity of the optimal particles was close to that of pure BT, and the dielectric constant was the greatest among the series of synthesized PMMA@BT particles. Thus, the optimized PMMA@BT particles demonstrated the strongest electroresponsive behavior in gelatin hydrogel elastomer, as demonstrated by polarized microscopy and dynamic mechanical analysis. The excellent electroresponsive property of the optimal PMMA@BT particles is reflected by the large sensitivity of the increase in storage modulus for the gelatin hydrogel elastomer containing the composite particles (21% at E = 0.8 kV mm⁻¹ and a particle loading of 1.0 wt%), far greater than that of pure BT particles (4.7%). Based on the sensitive electroresponsive properties, the PMMA@BT particles have potential applications as electroresponsive materials.

A series of core–shell-structured poly(methylmethacrylate)@BaTiO₃ (PMMA@BT) composite particles were constructed via the self-assembly of BT nanoparticles on the surfaces of PMMA cores through the covalent bonding of siloxane groups at room temperature.

Enantioseparation of propranolol, amlodipine and metoprolol by electrochromatography using an open tubular capillary modified with β-cyclodextrin and poly(glycidyl methacrylate) nanoparticles

The inner wall of a capillary was coated with glycidyl methacrylate (GMA) to form tentacle-type coating, and poly(glycidyl methacrylate) nanoparticles (PGMA NPs) were then immobilized on the film. Ethanediamine-β-cyclodextrin as chiral selector was covalently bonded into the PGMA NPs through the ring-open reaction. The materials were characterized by SEM, TEM and FT-IR. The modified column was applied to the enantioseparation of the racemates of propranolol, amlodipine and metoprolol. Compared to a capillary with a single layer of CD-PGMA (without GMA coating) and to a CD-GMA system (without PGMA nanoparticles), the performance of the capillary is strongly improved. The effects of buffer pH value and applied voltage were optimized. Best resolutions (propranolol: 1.27, metoprolol: 1.01 and amlodipine: 2.93) were obtained when using the PGMA-coated capillary system. The run-to-run, day-to-day and column-to-column reproducibility were tested and found to be highly attractive. The new stationary phase is likely to have a large potential and scope in that it may also be applied to chiral separations of other enantiomers, such as amino acids and biogenic amines. Graphical abstract Schematic presentation of the preparation of a capillary column with glycidyl methacrylate (GMA) coating which was then immobilized with poly(glycidyl methacrylate) nanoparticles and ethanediamine-β-cyclodextrin. This novel open tubular column was applied to construct capillary electrochromatography system for separation of basic racemic drugs.

Evaluation of the enantioselectivity of capillary electrokinetic chromatography using ethanediamine-bonded poly (glycidyl methacrylate) microspheres as the pseudostationary phases

In this work, a new capillary electrokinetic chromatography (EKC) approach using ethanediamine-bonded poly (glycidyl methacrylate) (Ami-PGMA) microspheres as pseudostationary phases (PSPs) for enantioseparation with a polysaccharide, chondroitin sulfate E (CSE), as the chiral selector. The CSE@Ami-PGMA EKC system was applied to enantioseparate basic drugs, and distinct improved separations of tested enantiomers were obtained while comparing with the single CSE system (the resolution increased from 0.41 to 1.26 for nefopam, from 1.24 to 2.15 for laudanosine, and from 0.92 to 2.36 for amlodipine). The Ami-PGMA microspheres were fully characterized by scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy, and the results showed Ami-PGMA microspheres were uniform and spherical in size (1 μm). Several principal parameters were systematically investigated, and the optimal chiral separations were obtained with Tris/H₃ PO₄ (20 mM, pH 2.4, and 3.4 for NEF) containing 2.5% (w/v) CSE and 20-μg Ami-PGMA microspheres in 20°C. Subsequently, the concentrations of Ami-PGMA microspheres and CSE were proved to be the dominant factors for the separation in the CSE@Ami-PGMA EKC system by Statistical Product and Service Solutions (SPSS).

Smart and Functional Conducting Polymers: Application to Electrorheological Fluids

Electro-responsive smart electrorheological (ER) fluids consist of electrically polarizing organic or inorganic particles and insulating oils in general. In this study, we focus on various conducting polymers of polyaniline and its derivatives and copolymers, along with polypyrrole and poly(ionic liquid), which are adopted as smart and functional materials in ER fluids. Their ER characteristics, including viscoelastic behaviors of shear stress, yield stress, and dynamic moduli, and dielectric properties are expounded and appraised using polarizability measurement, flow curve testing, inductance-capacitance-resistance meter testing, and several rheological equations of state. Furthermore, their potential industrial applications are also covered.

Polyaniline Coated Core-Shell Typed Stimuli-Responsive Microspheres and Their Electrorheology

Functional core-shell-structured particles have attracted considerable attention recently. This paper reviews the synthetic methods and morphologies of various electro-stimuli responsive polyaniline (PANI)-coated core-shell-type microspheres, including PANI-coated Fe₃O₄, SiO₂, Fe₂O₃, TiO₂, poly(methyl methacrylate), poly(glycidyl methacrylate), and polystyrene along with their electrorheological (ER) characteristics when prepared by dispersing these particles in an insulating medium. In addition to the various rheological characteristics and their analysis, such as shear stress and yield stress of their ER fluids, this paper summarizes some of the mechanisms proposed for ER fluids to further understand the responses of ER fluids to an externally applied electric field.

Post-polymerization modification reactions of poly(glycidyl methacrylate)s

Single and multiple post-polymerization modifications of poly(glycidyl methacrylate) scaffold through the nucleophilic ring-opening reactions of the pendent epoxide groups are described.

Synthesis of kenaf cellulose carbamate and its smart electric stimuli-response

Cellulose carbamate (CC) was produced from kenaf core pulp (KCP) via a microwave reactor-assisted method. The formation of CC was confirmed by Fourier transform infrared spectroscopy and nitrogen content analysis. The degree of substitution, zeta potential and size distribution of CC were also determined. The CC was characterized with scanning electron microscopy, X-ray diffraction and thermogravimetry analysis. The CC particles were then dispersed in silicone oil to prepare CC-based anhydrous electric stimuli-responsive electrorheological (ER) fluids. Rhelogical measurement was carried out using rotational rheometer with a high voltage generator in both steady and oscillatory shear modes to examine the effect of electric field strength on the ER characteristics. The results showed that the increase in electric field strength has enhanced the ER properties of CC-based ER fluid due to the chain formation induced by electric polarization among the particles.

Poly(glycidyl methacrylate)-functionalized magnetic nanoparticles as platforms for linking functionalities, bioentities and organocatalysts

Magnetic nanoparticles coated with polyglycidyl methacrylate are ring-opened by nucleophiles containing reactive centers, bioentities, organocatalysts leading to new materials.

Facile fabrication of core/shell structured SiO2/polypyrrole nanoparticles with surface modification and their electrorheology

We synthesized conductive polypyrrole (PPy) coated silica core–shell structured nanoparticles, and investigated their electrorheological (ER) characteristics under electric fields applied when dispersed in silicone oil.

Facile synthesis of polyaniline nanotubes and their enhanced stimuli-response under electric fields

Polyaniline (PANI) nanotubes were fabricated successfully using a micelle soft-template method in the presence of oxalic acid as a dopant and applied as the dispersed phase of an electrorheological (ER) fluid.