Facile Preparation of Raspberry-Like SiO@Polyurea Microspheres with Tunable Wettability and Their Application for Oil-Water Separation.

Raspberry-like microspheres have been widely used as superhydrophobic materials, photonic crystals, drug carriers, etc. Nevertheless, their preparation methods, usually consisting of multiple steps, are generally time- and energy-consuming. Herein raspberry-like SiO@polyurea microspheres (SiO@PUM) are readily prepared via a one-step precipitation polymerization of isophorone diisocyanate in a HO/acetone mixture with the presence of SiO particles.

Preparation of fluorescent polyurethane microspheres and their applications as reusable sensor for 4-nitrophenol detection and as microplastics model for visualizing polyurethane in cells and zebrafish.

Fluorescent microspheres are of significant interests due to their wide applications in biotechnology fields. However, their preparation presents several challenges, such as the need for dye labeling, the complexity of materials and often sophisticated preparation conditions. Here a simple process for hydrophilic and crosslinked polyurethane (CPU) microspheres, with carboxyl groups on the surface via one-step precipitation polymerization in 40 min, is presented.

Full Green Detection of Antibiotic Tetracyclines Using Fluorescent Poly(ethylene glycol) as the Sensor and the Mechanism Study.

Tetracyclines are well-known antibiotics and widely used against a variety of bacterial infections. Their monitoring and detection have been an important issue. To this end, a vast number of methods have been developed; fluorescence sensing is one of the most reported.

Fluorescent linear polyurea based on toluene diisocyanate: Easy preparation, broad emission and potential applications.

In contrast to conventional fluorescent polymers featured by large conjugation structures, a new class of fluorescent polymers without above conjugations are gaining constant interest owing to their significant academic importance and promising applications in diverse fields. These unconventional fluorescent polymers are in general composed of heteroatoms (e.g.

Highly Uniform and Porous Polyurea Microspheres: Clean and Easy Preparation by Interface Polymerization, Palladium Incorporation, and High Catalytic Performance for Dye Degradation.

Owing to their high specific surface area and low density, porous polymer materials are of great importance in a vast variety of applications, particularly as supports for enzymes and transition metals. Herein, highly uniform and porous polyurea microspheres (PPM), with size between 200 and 500 μm, are prepared by interfacial polymerization of toluene diisocyanate (TDI) in water through a simple microfluidic device composed of two tube lines, in one of which TDI is flowing and merged to the other with flowing aqueous phase, generating therefore TDI droplets at merging. The polymerization starts in the tube while flowing to the reactor and completed therein.

Preparation of Thermoresponsive Polymer Nanogels of Oligo(Ethylene Glycol) Diacrylate-Methacrylic Acid and Their Property Characterization.

Stimuli-responsive polymers have received growing attention in recent years owing to their wide applications in diverse fields. A novel stimuli-responsive polymer, based on oligo(ethylene glycol) diacrylate (OEGDA) and methacrylic acid (MAA), P(OEGDA-MAA), is prepared by precipitation polymerization and is shown to have a LCST-type VPTT (volume phase transition temperature) at 33 °C in water and a UCST-type VPTT at 43 °C in ethanol, all at concentration of 1 mg/mL. Both VPTTs are strongly concentration and pH dependent, providing an easy way to tune the phase transition temperature.

Pickering Emulsion Formation of Paraffin Wax in an Ethanol-Water Mixture Stabilized by Primary Polymer Particles and Wax Microspheres Thereof.

Stable dispersions of paraffin wax droplets and their nano- and microspheres have broad applications. Despite intensive efforts, the production of uniform wax spheres remains a challenge. For their preparation, abundant surfactants and other additives are commonly used to stabilize the dispersions.

Characterization of Heterocoagulation with Oppositely Charged Polymer Colloid Particles through Online Tracking of Light Transmittance.

Heterocoagulation of colloid particles with opposite surface charge has been used for the preparation of composite microspheres with specifically designed suprastructure, such as those with raspberry-like surface morphology and core-shell microspheres, which are difficult to achieve through other techniques. Here we report our investigation on the heterocoagulation of cationic polystyrene (PS) particles with anionic poly(methyl methacrylate) (PMMA) particles by a novel technique, i.e.

Immobilization of Lipase from Pseudomonas fluorescens on Porous Polyurea and Its Application in Kinetic Resolution of Racemic 1-Phenylethanol.

A porous polyurea (PPU) was prepared through a simple protocol by reacting toluene diisocyanate with water in binary solvent of water-acetone. Its amine group was determined through spectrophotometric absorbance based on its iminization with p-nitrobenzaldehyde amines. PPU was then used as a novel polymer support for enzyme immobilization, through activation by glutaraldehyde followed by immobilization of an enzyme, lipase from Pseudomonas fluorescens (PFL), via covalent bonding with the amine groups of lipase molecules.

Preparation of hollow TiO2 nanoparticles through TiO2 deposition on polystyrene latex particles and characterizations of their structure and photocatalytic activity.

In a mixed solvent of water and ethanol, polystyrene/titanium dioxide (PSt/TiO2) composite particles of core-shell structure were prepared by hydrolysis of tetrabutyl titanate in the presence of cationic PSt particles or anionic PSt particles surface-treated using γ-aminopropyl triethoxysilane. Hollow TiO2 particles were obtained through calcination of the PSt/TiO2 core-shell particles to burn off the PSt core or through dissolution of the core by tetrahydrofuran (THF). An alternative process constituted of preheating the PSt/TiO2 particles at 200°C to allow partial crystallization followed by calcination or PSt dissolution by THF.

Preparation and characterization of nanosized P(NIPAM-MBA) hydrogel particles and adsorption of bovine serum albumin on their surface.

Thermosensitive polymer hydrogel particles with size varying from 480 to 620 nm were prepared through precipitation copolymerization of N-isopropylacrylamide with N,N'-methylenebisacrylamide (MBA) in water with ammonium persulfate as the initiator. Only polymer hydrogels without any coagula were obtained when MBA concentration in the monomer mixture was kept between 2.5 and 10.

Comparisons of simple and complex coacervations for preparation of sprayable insect sex pheromone microcapsules and release control of the encapsulated pheromone molecule.

With dodecanol (C12OH) as a model molecule of insect sex pheromone as core material, natural polymers gelatin (GE) and acacia gum (AG) as wall materials, microcapsules aiming to be a sprayable environment-friendly pesticide were prepared via GE simple coacervation and complex coacervation of GE and AG. C12OH encapsulation in complex coacervation was higher than those in simple coacervation. Its encapsulation was enhanced with increase in wall material cross-linking.

Precipitation Polymerization in Ethanol and Ethanol/Water to Prepare Uniform Microspheres of Poly(TMPTA-styrene).

The precipitation polymerization of styrene-trihydroxymethyl propane triacrylate has been carried out using ethanol and an ethanol/water mixture as the solvent. Uniform microspheres with high monomer conversion are achieved within 4 h, a much shorter polymerization time than that reported for the precipitation polymerization of divinyl benzene-styrene in acetonitrile. The results clearly demonstrate that use of water as a co-solvent is indeed very effective to promote the polymerization to high conversion and to obtain uniform microspheres.

Spreadable dispersion of insect sex pheromone capsules, preparation via complex coacervation and release control of the encapsulated pheromone component molecule.

Using insect female pheromone to disrupt their mating process is a new technology, which has been applied as environment friendly pesticides in agricultural and forestry industries to control pest infestation. Dodecanol (C(12)OH), as one of the simple pheromone component, was chosen and encapsulated as core material using gelatin (GE) and acacia gum (AG) as wall materials via complex coacervation. Through variations in capsule preparations, particularly the crosslinking density of the wall materials, release controllability of C(12)OH was studied.