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polystyrene latex

Astha Garg, Charles A Cartier, Kyle J M Bishop, Darrell Velegol
The zeta potential of a particle characterizes its motion in an electric field and is often thought to be negligible at high ionic strength (several moles per liter) due to thinning of the electrical double layer (EDL). Here, we describe zeta potential measurements on polystyrene latex (PSL) particles at monovalent salt concentrations up to saturation (~ 5 M NaCl) using electrophoresis in sinusoidal electric fields and high-speed video microscopy. Our measurements reveal that the zeta potential remains finite at even the highest concentrations...
October 21, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Hamza Al-Shehri, Tommy S Horozov, Vesselin N Paunov
We prepared model porous composite supra-particles and investigated the effect of the initial infused fluid phase on their attachment at the liquid-fluid interface. We used a simple method for fabrication of millimetre-sized spherical porous supra-particles from much smaller monodisperse latex microparticles as building blocks by evaporation of a polystyrene sulphate latex suspension on a hot super-hydrophobic surface. We annealed the dried supra-particles at the polymer's glass transition temperature to fuse partially their latex particle building blocks...
October 12, 2016: Soft Matter
Vesselin N Paunov, Hamza Al-Shehri, Tommy S Horozov
We developed and tested a theoretical model for the attachment of fluid-infused porous supra-particles to a fluid-liquid interface. We considered the wetting behaviour of agglomerated clusters of particles, typical of powdered materials dispersed in a liquid, as well as of the adsorption of liquid-infused colloidosomes at the liquid-fluid interface. The free energy of attachment of a composite spherical porous supra-particle made from much smaller aggregated spherical particles to the oil-water interface was calculated...
September 29, 2016: Physical Chemistry Chemical Physics: PCCP
Hongyan Cao, Libin Zhang, Lili Wu, Xiang Zheng Kong
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., by following online the evolution of the light transmittance in the process with practically no disturbance of the dispersion and no post-treatment for the samples...
October 12, 2016: ACS Applied Materials & Interfaces
Jani Tuoriniemi, Beatriz Moreira, Gulnara Safina
The capabilities of surface plasmon resonance (SPR) for characterization of colloidal particles were evaluated for 100, 300, and 460 nm nominal diameter polystyrene (PS) latexes. First the accuracy of measuring the effective refractive index (neff) of turbid colloids using SPR was quantified. It was concluded that for submicrometer sized PS particles the accuracy is limited by the reproducibility between replicate injections of samples. An SPR method was developed for obtaining the particle mean diameter (dpart) and the particle number concentration (cp) by fitting the measured neff of polystyrene (PS) colloids diluted in series with theoretical values calculated using the coherent scattering theory (CST)...
October 4, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Pascal Pratte, Stéphane Cosandey, Catherine Goujon-Ginglinger
CONTEXT: Knowledge of the droplet size distribution of inhalable aerosols is important to predict aerosol deposition yield at various respiratory tract locations in human. Optical methodologies are usually preferred over the multi-stage cascade impactor for high-throughput measurements of aerosol particle/droplet size distributions. OBJECTIVE: Evaluate the Laser Aerosol Spectrometer technology based on Polystyrene Sphere Latex (PSL) calibration curve applied for the experimental determination of droplet size distributions in the diameter range typical of commercial e-cigarette aerosols (147-1361 nm)...
October 2016: Inhalation Toxicology
Samy Rengasamy, Ronald Shaffer, Brandon Williams, Sarah Smit
NIOSH published a Federal Register Notice to explore the possibility of incorporating FDA required filtration tests for surgical masks (SMs) in the 42 CFR Part 84 respirator certification process. There have been no published studies comparing the filtration efficiency test methods used for NIOSH certification of N95 filtering facepiece respirators (N95 FFRs) with those used by the FDA for clearance of SMs. To address this issue, filtration efficiencies of "N95 FFRs" including six N95 FFR models and three surgical N95 FFR models, and three SM models were measured using the NIOSH NaCl aerosol test method, and FDA required particulate filtration efficiency (PFE) and bacterial filtration efficiency (BFE) methods, and viral filtration efficiency (VFE) method...
August 19, 2016: Journal of Occupational and Environmental Hygiene
Kabindra M Shakya, Alyssa Noyes, Randa Kallin, Richard E Peltier
Inexpensive cloth masks are widely used in developing countries to protect from particulate pollution albeit limited data on their efficacy exists. This study examined the efficiency of four types of masks (three types of cloth masks and one type of surgical mask) commonly worn in the developing world. Five monodispersed aerosol sphere size (30, 100, and 500 nm, and 1 and 2.5 μm) and diluted whole diesel exhaust was used to assess facemask performance. Among the three cloth mask types, a cloth mask with an exhaust valve performed best with filtration efficiency of 80-90% for the measured polystyrene latex (PSL) particle sizes...
August 17, 2016: Journal of Exposure Science & Environmental Epidemiology
Zenamarkos Bantie Sendekie, Arthur Gaveau, Rob G H Lammertink, Patrice Bacchin
Clogging of channels by complex systems such as mixtures of colloidal and biological particles is commonly encountered in different applications. In this work, we analyze and compare the clogging mechanisms and dynamics by pure and mixture suspensions of polystyrene latex particles and Escherichia coli by coupling fluorescent microscopic observation and dynamic permeability measurements in microfluidic filters. Pure particles filtration leads to arches and deposit formation in the upstream side of the microfilter while pure bacteria form streamers in the downstream zone...
2016: Scientific Reports
Isleine P Caldas, Miriam Z Scelza, Marco A Gallito, Gutemberg Alves, Licínio Silva
AIMS: The aim of this study is to evaluate the in vitro response of human gingival fibroblasts in primary cultures to two materials for temporary relining of dentures: Temporary Soft (TDV, Brazil) and Trusoft (Bosworth, USA) for 24 hours, 7 and 30 days by using a multi-parametric analysis. MATERIALS AND METHODS: Each material sample (TDV, TS, Polystyrene, Latex) was prepared and incubated in a culture medium for 1, 7, and 30 days at 37°C. Human gingival fibroblasts were exposed to the extracts and cell viability was evaluated by a multi-parametric assay, which allowed sequential analysis of mitochondrial activity (XTT), membrane integrity [neutral red (NR)], and cell density [crystal violet dye exclusion (CVDE)] in the same cells...
2016: Journal of Contemporary Dental Practice
Shuang Guo, Bai-Ling Qiu, Chen-Qi Zhu, Ya-Ya Gao Yang, Di Wu, Qi-Hui Liang, Nan-Yin Han
Gravitational field-flow fractionation (GrFFF) is a useful technique for separation and characterization for micrometer-sized particles. Elution behavior of micrometer-sized particles in GrFFF was researched in this study. Particles in GrFFF channel are subject to hydrodynamic lift forces (HLF), fluid inertial forces and gravity, which drive them to different velocities by carrier flow, resulting in a size-based separation. Effects of ionic strength, flow rate and viscosity as well as methanol were investigated using polystyrene latex beads as model particles...
September 15, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Ljiljana Palangetic, Kirill Feldman, Raphael Schaller, Romana Kalt, Walter R Caseri, Jan Vermant
This work revisits the synthesis of the colloidal particles most commonly used for making model near hard suspensions or as building blocks of model colloidal gels, i.e. sterically stabilised poly(methyl methacrylate) (PMMA) particles. The synthesis of these particles is notoriously hard to control and generally the problems are ascribed to the difficulty in synthesising the graft stabiliser (PMMA-g-PHSA). In the present work, it is shown that for improving the reliability of the synthesis as a whole, control over the polycondensation of the 12-polyhydroxystearic acid is the key...
July 14, 2016: Faraday Discussions
Lu Wang, Mingwang Pan, Shaofeng Song, Lei Zhu, Jinfeng Yuan, Gang Liu
Herein, we demonstrate a facile approach to prepare anisotropic poly(tert-butyl acrylate)/polystyrene (PtBA/PS) composite particles with controllable morphologies by soap-free seeded emulsion polymerization (SSEP). In the first step, noncrosslinked PtBA seeds with self-stabilizing polar functional groups (e.g., ester groups and radicals) are synthesized by soap-free emulsion polymerization. During the subsequent SSEP of styrene (St), PS bulges are nucleated on the PtBA seeds due to the microphase separation confined in the latex particles...
August 9, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Manigandan Sabapathy, Yogesh Shelke, Madivala G Basavaraj, Ethayaraja Mani
Non-spherical patchy particles are potential candidates as building blocks for the design of target colloidal structures via spontaneous self-organization. We report a facile scheme to synthesize non-spherical particles with patchy electrostatic interactions. In this method, charged spherical latex particles such as polystyrene (PS) are deformed unequally at an oil-water interface due to heating and partial swelling. The spherical particles then evolve into non-spherical shapes such as 'acorn-like' and 'idly-like'...
July 6, 2016: Soft Matter
E V Parkhomchuk, D G Gulevich, A I Taratayko, A M Baklanov, A V Selivanova, T A Trubitsyna, I V Voronova, P N Kalinkin, A G Okunev, S A Rastigeev, V A Reznikov, V S Semeykina, K A Sashkina, V V Parkhomchuk
Accelerator mass spectrometry (AMS) was shown to be applicable for studying the penetration of organic aerosols, inhaled by laboratory mice at ultra-low concentration ca. 10(3) cm(-3). We synthesized polystyrene (PS) beads, composed of radiocarbon-labeled styrene, for testing them as model organic aerosols. As a source of radiocarbon we used methyl alcohol with radioactivity. Radiolabeled polystyrene beads were obtained by emulsifier-free emulsion polymerization of synthesized (14)C-styrene initiated by K2S2O8 in aqueous media...
September 2016: Chemosphere
Barthélémy Brunier, Nida Sheibat-Othman, Mehdi Chniguir, Yves Chevalier, Elodie Bourgeat-Lami
Clay-armored polymer particles were prepared by emulsion polymerization in the presence of Laponite platelets that adsorb at the surface of latex particles and act as stabilizers during the course of the polymerization. While Laponite RDS clay platelets are most often used, the choice of the type of clay still remains an open issue that is addressed in the present article. Four different grades of Laponite were investigated as stabilizers in the emulsion polymerization of styrene. First, the adsorption isotherms of the clays, on preformed polystyrene particles, were determined by ICP-AES analysis of the residual clay in the aqueous phase...
June 21, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Nariman Yousefi, Andreas Wargenau, Nathalie Tufenkji
Identifying the mechanisms of nanoparticle (NP) interactions with cell membranes is key to understanding potential NP cytotoxicity and applications as nanocarriers for targeted drug delivery. To elucidate these mechanisms of interaction, supported phospholipid bilayers (SPBs) are commonly used as models of cell membranes. However, SPBs are soft thin films, and, as such, their properties can be significantly affected by the underlying substrate. Free-floating cell membranes would be best modeled by weakly adhered SPBs; thus, we propose a method for tailoring the interfacial interaction of an electrically charged SPB-substrate system based on modulations in the solution chemistry...
June 15, 2016: ACS Applied Materials & Interfaces
I Mirzaee, M Song, M Charmchi, H Sun
Capturing airborne particles from air into a liquid is a critical process for the development of many sensors and analytical systems. A miniaturized airborne particle sampling device (microimpinger) has been developed in this research. The microimpinger relies on a controlled bubble generation process produced by driving air through microchannel arrays. The particles confined in the microscale bubbles are captured in the sampling liquid while the bubbles form, are released and travel in a millimetre-scale sealed liquid reservoir...
June 21, 2016: Lab on a Chip
Tatsuo Aikawa, Akihiro Mizuno, Michinari Kohri, Tatsuo Taniguchi, Keiki Kishikawa, Takayuki Nakahira
Luminescent particles have been attracting significant attention because they can be used in biochemical applications, such as detecting and imaging biomolecules. In this study, luminescent polystyrene latex particles were prepared through miniemulsion polymerization of styrene with dissolved europium complexes in the presence of bovine serum albumin (BSA) and poly(ethylene glycol) monomethoxy methacrylate as surfactants. The solubility of the europium complex in styrene has a strong effect on the yield of the particle...
September 1, 2016: Colloids and Surfaces. B, Biointerfaces
Brendan M Heffernan, Yuli W Heinson, Justin B Maughan, Amitabha Chakrabarti, Christopher M Sorensen
An apparatus was designed and assembled to measure scattered light in the range of 180°±6° where enhanced backscattering, the cause of a glory, occurs. The apparatus was calibrated and tested using Fraunhofer circular aperture diffraction, angle of incidence correction, and a diffuse reflector. Theory indicates that backscattering is strongly dependent on particle size, refractive index, and shape. Experimental measurements from polystyrene latex spheres of two sizes and water droplets showed good agreement with Mie theory, but also indicated the extreme sensitivity of the backscattering to particle parameters...
April 20, 2016: Applied Optics
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