Surface Of Polystyrene Particles Research Articles

Alteration of zeta potential and cell viability in rat-derived L6 skeletal muscle cells and H9c2 cardiomyocytes: A study with submicron polystyrene particles.

Microand nanoplastics pollution can cause substantial damage to ecosystems. Since scientists have focused mainly on their impact on aquatic environments, less attention has been paid to the accumulation of polymer particles in terrestrial organisms. We checked if submicron (<5 mm) polystyrene (PS) particles, which can accumulate in living organisms, lead to changes in the physicochemical properties of mammalian cell membranes. The influence of submicron PS particles on the properties of rat-derived L6 myocytes and H9c2 cardiomyocytes was analyzed. Non-functionalized and amine-functionalized PS particles of 100 nm and 200 nm in diameter were used. The MTT assay was performed to evaluate the viability of the polymers-treated cells. The effect of short (6 h) and prolonged (48 h) incubation with different concentrations of PS particles on the cell's zeta (ζ) potential was examined with the electrophoretic light scattering technique (ELS). Polystyrene particles' physicochemical characteristics (size and stability) were performed using dynamic light scattering (DLS) and electrophoretic light scattering methods. The results show that submicron PS particles affect cell viability and cause changes in the physiochemical parameters of rat cell membranes. Differences were observed depending on the origin of the cells. We observed doseand time-dependent alterations in the studied parameters after submicron PS particle incubation in L6 myotubes and H9c2 cardiomyocytes. The size and modification of PS particle surfaces determine the extent to which they affect the analyzed properties of rat cardiomyocytes and myocytes membranes.

Synthesis of Polystyrene@TiO2 Core–Shell Particles and Their Photocatalytic Activity for the Decomposition of Methylene Blue

In this study, we investigated the preparation conditions of polystyrene (PS)@TiO2 core–shell particles and their photocatalytic activity during the decomposition of methylene blue (MB). TiO2 shells were formed on the surfaces of PS particles using the sol–gel method. Homogeneous PS@TiO2 core–shell particles were obtained using an aqueous NH3 solution as the promoter of the sol–gel reaction and stirred at room temperature. This investigation revealed that the temperature and amount of the sol–gel reaction promoter influenced the morphology of the PS@TiO2 core–shell particles. The TiO2 shell thickness of the PS@TiO2 core–shell particles was approximately 5 nm, as observed using transmission electron microscopy. Additionally, Ti elements were detected on the surfaces of the PS@TiO2 core–shell particles using energy-dispersive X-ray spectroscopy analysis. The PS@TiO2 core–shell particles were used in MB decomposition to evaluate their photocatalytic activities. For comparison, we utilized commercial P25 and TiO2 particles prepared using the sol–gel method. The results showed that the PS@TiO2 core–shell particles exhibited higher activity than that of the compared samples.

Hollow particles synthesized by water-soluble and oil-soluble initiators and the mechanism of incorporating an oil-soluble initiator

Monodisperse polystyrene particles were first synthesized by soap-free emulsion polymerization to enhance the monodispersity of hollow particles. Thereafter, the polystyrene particles were immersed in an aqueous solution of 2,2′-azobis(2-methylbutyronitrile) (V-59) to allow the particles to absorb V-59 while maintaining their monodispersity. Thermogravimetric measurements using p-styrenesulfonic acid sodium salt revealed that this absorption occurred not through electrostatic interactions but through hydrophobic ones. Subsequently, the TEOS sol-gel reaction was performed on the polystyrene particle surface to create a silica shell with the help of N-vinyl acetoamide. Finally, the synthesized particles were heated to induce the decomposition reaction of V-59 (which emits nitrogen gas) in the particles, thereby creating a hollow structure as the gas stayed in the particle. These procedures enabled the synthesis of monodisperse hollow particles.

Facile fabrication of polystyrene particles/graphene composites for improved dielectric and thermal properties

ABSTRACTIn this paper, polystyrene (PS)-based reduced graphene oxide (rGO) composites were prepared by mixing PS latex particles with graphene oxide (GO) and the following in-situ reduction. The structure and morphology of PS/rGO composites were characterized, and the effects of rGO content on the dielectric properties as well as thermal stability of PS/rGO composites were investigated. Results showed that rGO sheets armoured on the surface of PS particles and exhibited well dispersion in the PS matrix after hot compression. The introduction of rGO improved the dielectric properties of the composites remarkably. When rGO content was 0.12 vol%, the dielectric permittivity and breakdown strength of PS/rGO arrived at 6.3 at102 Hz and 107 kV/mm, with 50% and 35.4% enhancement compared to the pristine PS. Furthermore, PS/rGO presented better thermal stability than the pristine PS, but the overlapping of rGO sheets in PS matrix induced the instability of dielectric loss with frequency.

Heavy Metal Adsorption and Release on Polystyrene Particles at Various Salinities

Microplastics (MPs) and heavy metals are two major types of pollutants that interact with each other, but they are poorly understood. Polystyrene (PS) is one type of MPs that is often detected in aquatic environments. In this study, we examined the adsorption capacity and release rate of heavy metals with respect to different particle sizes of PS, heavy metals, initial heavy metal concentrations, and salinities. Virgin (new) PS with diameters of 20, 50, 130, and 250 μm was used in this study, and four heavy metals (lead, cadmium, copper, and zinc) were used. The results showed that larger PS particle sizes adsorbed more heavy metals even though it took longer to achieve equilibrium adsorption. An increase in heavy metal concentration caused the adsorption capacity (μg g–1) of PS particles to also increase, but the adsorption rate (%) decreased. Increased salinity of the heavy metal solution resulted in a slower adsorption time and a lower adsorption capacity and release rate from the surface of PS particles. Different heavy metals also had different adsorption capacities. Pb was consistently more highly adsorbed by MPs, followed by Cu, Zn, and Cd. Larger PS sizes released heavy metals faster than smaller PS sizes, and the amounts of heavy metals released were higher. The heavy metal with the highest release rate was Cd, followed by Pb, Cu, and Zn. Finally, our findings highlight the interactions between PS and heavy metals and strongly support that PS particles can act as vectors for heavy metals in aquatic systems.

Spectroscopic Investigation of Increased Fluorescent Intensity of Fluorescent Dyes When Adsorbed onto Polystyrene Microparticles.

Microplastics as environmental pollutants are increasingly a source of alarm. The characterization of microplastics will be necessary to discriminate microplastics from other types of particles. To discriminate specific microplastics, plastic-adsorbable fluorescent dyes are used, the stained microplastics are separated from the dye-microplastic mixture by filtration, and the type of fluorescent staining of the microplastics is analyzed by fluorescent microscopy. In this study, to realize the in situ analysis of fluorescent staining, i.e., to discriminate microplastics without any separation or filtration processes, we studied the change in the fluorescent properties after adsorption of the fluorescent dyes to the microplastic particle surfaces using a 3D excitation emission matrix fluorescence spectroscopy (the excitation wavelength-dependent emission spectrum). We used three fluorescent dyes: Fluorescein, Rhodamine 6G, and Methylene Blue, and polystyrene microparticles as our model microplastic. Fluorescein and Methylene Blue showed increases in the fluorescent intensity, while Rhodamine 6G showed negligible intensity changes. This is likely due to the degree of affinity of the dyes to the polystyrene particle surface, the structural stability of the dyes on the surface, and the changes in the environment around the dyes after the adsorption of each dye to the surface. We conclude that we have demonstrated the potential to look for appropriate fluorescent dyes using the method studied here to identify and estimate individual plastic materials.

Description of Polystyrenella longa gen. nov., sp. nov., isolated from polystyrene particles incubated in the Baltic Sea

Planctomycetes occur in almost all aquatic ecosystems on earth. They have a remarkable cell biology, and members of the orders Planctomycetales and Pirellulales feature cell division by polar budding, perform a lifestyle switch from sessile to motile cells and have an enlarged periplasmic space. Here, we characterise a novel planctomycetal strain, Pla110T, isolated from the surface of polystyrene particles incubated in the Baltic Sea. After phylogenetic analysis, the strain could be placed in the family Planctomycetaceae. Strain Pla110T performs cell division by budding, has crateriform structures and grows in aggregates or rosettes. The strain is a chemoheterotroph, grows under mesophilic and neutrophilic conditions, and exhibited a doubling time of 21 h. Based on our phylogenetic and morphological characterisation, strain Pla110T (DSM 103387T = LMG 29693T) is concluded to represent a novel species belonging to a novel genus, for which we propose the name Polystyrenella longa gen. nov., sp. nov.

On-Flow Immobilization of Polystyrene Microspheres on β-Cyclodextrin-Patterned Silica Surfaces through Supramolecular Host-Guest Interactions.

Species-specific isolation of microsized entities such as microplastics and resistant bacteria from waste streams is becoming a growing environmental challenge. By studying the on-flow immobilization of micron-sized polystyrene particles onto functionalized silica surfaces, we ascertain if supramolecular host–guest chemistry in aqueous solutions can provide an alternative technology for water purification. Polystyrene particles were modified with different degrees of adamantane (guest) molecules, and silica surfaces were patterned with β-cyclodextrin (β-CD, host) through microcontact printing (μCP). The latter was exposed to solutions of these particles flowing at different speeds, allowing us to study the effect of flow rate and multivalency on particle binding to the surface. The obtained binding profile was correlated with Comsol simulations. We also observed that particle binding is directly aligned with particle’s ability to form host–guest interactions with the β-CD-patterned surface, as particle binding to the functionalized glass surface increased with higher adamantane load on the polystyrene particle surface. Because of the noncovalent character of these interactions, immobilization is reversible and modified β-CD surfaces can be recycled, which provides a positive outlook for their incorporation in water purification systems.

Carboxylic acid modified pH-responsive composite polymer particles

Abstract pH-responsive polymers are attracting much interest from researchers because of their wide application potentials in areas like biosensor, bioseparator, bioreactor, biocatalysis, drug delivery, and water treatments. In this investigation a two-step process is evaluated to prepare carboxyl(–COOH) functional submicrometer-sized pH-responsive composite polymer particles. First, submicrometer-sized polystyrene (PS) particles are prepared by a modified conventional dispersion polymerization. In the second step, PS/poly(methacrylic acid-acrylamide-ethylene glycol dimethacrylate) [PS/P(MAA-AAm-EGDMA)] composite polymer particles are synthesized by seeded co-polymerization of methacrylic acid, acrylamide, and ethylene glycol dimethacrylate in the presence of PS seed particles. The size distributions and morphologies analyzed by electron micrographs suggested that seeded copolymerization smoothly occurred without formation of any secondary tiny copolymer particles. The surface composition and functionality are confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. The hydrodynamic diameter increased with the increase in pH values as part of the carboxyl groups are deprotonated, which favored the swelling of copolymer layer formed around the surface of PS particles. The adsorption of cationic and anionic surfactants at two different pH values showed that adsorption of cationic surfactant is favored at higher pH value whereas that of anionic surfactant is favored at lower pH value.

Experimental Study of the Motion of Patchy Particle Swimmers Near a Wall

In this work, we demonstrate our ability to precisely tailor the surface activity of self-propelled active colloids by varying the size of the active area. The quasi two-dimensional autonomous motion of spherical patchy particle swimmers is studied in a chemical environment in the vicinity of a solid boundary. Oxidative decomposition of hydrogen peroxide into oxygen and water occurs only on a well-defined Pt-coated section of the polystyrene particle surface. The asymmetric distribution of product molecules interacting with the particle leads to the autonomous motion, which is characterized as the patch size varies from 11 to 25 to 50% of the particle surface area. The phoretic motion of patchy particle swimmers is analytically predicted by a model developed by Popescu et al. and shows good agreement with the experimentally observed velocities when the influence of the wall on the preferential rotational motion of the particles near the solid boundary is considered. The study illustrates the potential to precisely engineer the motion of particles by controlling their properties rather than depending on changes in the environment.

Polystyrene–Polyhedral Oligomeric Silsesquioxane Core–Shell Element-block Polymer Particles Fabricated via Heterocoagulation Method

Colloidally stable polystyrene (PS)–polyhedral oligomeric silsesquioxane (POSS) element-block polymer particles were fabricated by heterocoagulation method using negatively charged POSS and positively charged PS seed particles in water. POSS was adsorbed to the PS particle surface via electrostatic interaction and the resulting particles had PS core and POSS shell morphology.

A facile approach for preparation of polystyrene/graphene nanocomposites with ultra-low percolation threshold through an electrostatic assembly process

Improving the dispersion of graphene nanosheets (GN) in a polymer matrix is a critical step in lowering the percolation threshold of nanocomposites. In this paper, an effective method based on an electrostatic assembly process is reported. Polystyrene (PS) latex was first prepared by using hexadecyl trimethyl ammonium bromide (CTAB) as a cationic surfactant, which created positive charges on the surface of the PS micelles. An in situ demulsification process was then conducted by adding negatively charged graphene oxide (GO) particles into the positively charged PS latex. Thus, GO sheets were attached spontaneously to the surfaces of PS particles through electrostatic adsorption. Followed by in situ reduction and hot pressing, the agglomeration of GN was largely prohibited by the PS microspheres and facilitated the formation of GN networks in the PS matrix. The obtained PS/GN nanocomposites exhibited excellent electrical properties with a percolation threshold as low as 0.054 vol.% GN. When the GN content reached 1.53 vol.%, the electrical conductivity was 46.32 S/m and the thermal conductivity 0.47 W/mk. This strategy represents a new environment-friendly pathway, which is also applicable for other polymer matrices, for large-scale production of polymer composites with fully interconnected graphene networks at ultra-low GN content.

Multifunctional and robust composite materials comprising gold nanoparticles at a spherical polystyrene particle surface.

The preparation of a family of composite particles comprising gold nanoparticles (AuNP) assembled at a polystyrene (PS) surface is reported. Tunable loading is demonstrated for AuNP sizes (4.5-26 nm). The robust composites are stable to multiple centrifugation and dispersion cycles and to conditions of high ionic strength, physiological buffer and cell culture media. These properties provide potential for a variety of applications from cellular studies to catalysis.

Surface-initiated anionic polymerization of [1]silaferrocenophanes for the preparation of colloidal preceramic materials.

A novel strategy for the preparation of poly(ferrocenylsilane) (PFS) immobilized on the surface of cross-linked polystyrene (PS) nanoparticles is reported. The ferrocene-containing core/shell architectures are shown to be excellent candidates as preceramic polymers yielding spherical ceramic materials consisting of iron silicide (Fe3 Si) and metallic iron after thermal treatment. For this purpose, dimethyl- and hydromethyl[1]silaferrocenophane monomers are polymerized by surface-initiated ring-opening polymerization upon taking advantage of residual vinylic moieties at the PS particle surface. A strategy for selective chain growth from the particle surface is developed without the formation of free PFS homopolymer in solution. The grafted particles are characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). These particles are excellent precursors for ceramics as studied by thermogravimetric analysis (TGA). The composition of the ceramics is studied using X-ray diffraction (XRD) measurements, while the morphology is probed by scanning electron microscopy (SEM) revealing the original spherical shape of the precursor particles. Obtained ceramic materials- predominantly based on iron silicides-show ferromagnetic behavior as investigated by superconducting quantum interference device (SQUID) magnetization measurements at different temperatures.

Tuning the particle-surface interactions in aqueous solutions by soft microgel particles.

Due to the softness and deformability, interaction between colloidal surfaces induced by soft particles varies in a more complex way than for solid particles and thus has attracted much attention in recent years. In the present study, we use total internal reflection microscopy (TIRM) to directly measure the interaction between polystyrene (PS) microparticles and a flat glass surface in a poly(N-isopropylacrylamide) (PNIPAM) microgel dispersion with concentration varying from dilute (0.1 wt %) to highly concentrated regime (7.5 wt %). Our result shows that the PS particle-surface interactions mediated by the soft microgels are greatly affected by the particle concentration, the configuration of those microgels adsorbed on the surfaces, and the structure and packing of microgels in bulk solution. With increasing the microgel concentration (Cmicrogel), the interaction between the PS particle and surface turned from bridging attraction to steric repulsion, and then depletion attraction, which were mainly governed by the adsorption amount and configuration of microgels on the two surfaces. By further increasing Cmicrogel to condensed situation, structural force with oscillated energy wells was detected. The variation of interactions induced by the soft microgels was further confirmed by optical imaging. Crystallization of the PS microparticles appeared at moderate Cmicrogel; however, crystallization was hindered at higher Cmicrogel where the microgels are highly packed in the bulk solution. Furthermore, using TIRM, microgel packing with local energy well (0.1-1.0 kBT) at the highly condensed state (7.5 wt %) was resolved from the interaction profiles. Therefore, the shear force and modulus generated by such microgel packing can be determined as ∼0.2 pN and tens of mPa, respectively, which are much weaker than data given by conventional active methods.

Preparation of Laponite-Armored Polystyrene Particles by Pickering Emulsion Polymerization

Laponite-armored polystyrene (PS) particles were fabricated by Pickering emulsion polymerization. Emulsions of styrene dispersed in water were stabilized by hydrophobic modified Laponite nanodiscs. The properties of PS particles were investigated by TEM, SEM and DLS. The results show that these particles have narrow size distribution with diameter around 160 nm, which attributes to the improvable wettibility of modified Laponite stabilizer. TEM result proves that Laponite nanodiscs are on the surface of PS particles.

그래핀 산화물-구형 고분자 입자 사이의 흡착 거동

고분자 입자에 그래핀이 코팅된 복합체를 제조하고 구조 및 형태변화를 통한 그래핀의 새로운 응용 가능성이 제기되고 있다. 그래핀이 표면에 흡착된 폴리스티렌 복합입자의 물성제어를 위해서, 물 분산매 하에 혼합방법과 혼합순서를 달리하여 흡착반응 시간과 혼합물 내의 순간적인 상대농도 차이를 조사하였다. 유화중합으로 중합된 폴리스티렌 입자에 폴리에틸렌이민을 흡착시켜 표면에 양전하를 갖게 만든 고분자 입자와, 흑연의 화학적 박리법으로 표면에 음전하를 갖도록 제조된 그래핀 산화물과의 서로 반대되는 전하를 갖는 두 입자의 흡착을 유도한 결과 흡착반응 시간이 길수록, 순간 상대 농도차가 클수록 균질하게 표면 코팅이 만들어지고, 응집이 적은 복합 입자를 제조할 수 있었다. Graphene-coated polymer particles have attracted research interests due to their emerging applications derived from their controlled structure and morphology. To control the properties of graphene oxide (GO)-polystyrene (PS) composite particles, the adsorption time and instantaneous adsorption conditions were investigated by varying their mixing method. Polystyrene particles prepared by emulsion polymerization were modified to have positive surface charge by adsorption of polyethylene imine (PEI) on the surface of PS particles. GO prepared by the chemical exfoliation method had negative surface charge from the oxygenated groups. The adsorption of the negatively charged GOs onto the positively charged PS particles was successfully completed, and it was found that a longer adsorption time and a greater difference in the instantaneous relative concentration led PS-GO particles to have more homogeneously coated surfaces without aggregation.

Facile and controllable synthesis of polystyrene/palladium nanoparticle@polypyrrole nanocomposite particles

Herein is reported a facile and controllable route for coating polystyrene (PS) particles with palladium nanoparticle@polypyrrole (PdNP@PPy) nanocomposites based on the “Swelling–Diffusion–Interfacial-Polymerization Method” (SDIPM). The formation of PdNP@PPy nanocomposites was achieved by using palladium chloride as the oxidant for pyrrole. The synthesized PS/PdNP@PPy nanocomposite particles were characterized extensively by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared and Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetry, and C, H, and N elemental microanalyses. Significantly, it is clearly found that highly dispersed PdNPs with small size are well embedded in the PPy shell. Moreover, the resultant PS/PdNP@PPy nanocomposite particles have a well-defined core/shell structure, and then the mass loading of PdNP@PPy nanocomposites on the surface of PS particles can be controlled simply by changing the weight ratio of pyrrole/PS. The synthesized PS/PdNP@PPy nanocomposite particles also show good catalytic activity and reusability in the reduction of p-nitrophenol by NaBH4.

Synthesis and Characterization of β‐CD‐Coated Polystyrene Microspheres by γ‐Ray Radiation Emulsion Polymerization

Polystyrene (PS) microspheres coated with β-cyclodextrin (β-CD) were fabricated via γ-ray-induced emulsion polymerization in a ternary system of styrene/β-CD/water (St/β-CD/water). The solid inclusion complex of St and β-CD particles formed at the St droplets-water interface can stabilize the emulsion as the surfactant. TEM and XPS results showed that β-CD remains on the surface of PS particles. The average size of the PS particles increases from 186 to 294 nm as the weight ratio of β-CD to St rises from 5% to 12.5%. The water contact angle (CA) of PS latex film is lower than 90°, and reduces with the β-CD content even to 36°. Thus, this work provides a new and one-pot strategy to surface hydrophilic modification on hydrophobic polymer particles with cyclodextrins through radiation emulsion polymerization.

Effect of monomer and hydrocarbon content and polarity of the medium on the preparation of nonspherical particles via seeded dispersion polymerization in the presence of saturated hydrocarbon droplets

In this work, the preparation of micron-sized polymer particles with nonspherical shapes via seeded dispersion polymerization of 2-ethylhexyl methacrylate (EHMA) with polystyrene (PS) seed particles in the presence of decane droplets and evaporation of decane after the polymerization under various polymerization conditions was discussed. The effect of monomer and decane content and polarity of the medium on the shape of the obtained particles was investigated. The experimental results showed that decreasing the amount of monomer and hydrocarbon volume of PEHMA/hydrocarbon domains, the particles decreased but they grew symmetrically, resulting in symmetric shapes. Furthermore, it was suggested that because of changing the solubility of the oligoradicals and hydrocarbon in the medium, the shape of the particles changed with changing the polarity of the medium. With decreasing the polarity of the medium, solubility of the oligoradicals in the medium increases and bigger polymer domains form on the surface of PS particles which can absorb higher amounts of decane. All of these can contribute to an increase in volume reduction after extraction of PEHMA/decane, resulting in various particle shapes. Further decreasing in polarity of the medium leads to an increase in the solubility of decane in the medium and decreasing the absorbed amount of decane by PS particles and PEHMA domains, resulting in lower volume reduction after evaporation of decane.