Adhesion Of Polystyrene Research Articles

Enhanced sorption of hyper-cross-linked polymers for enrofloxacin via polystyrene adhesion: Exploring the feasibility of a collaborative treatment approach for emerging contaminants

The conventional treatment processes adopted by wastewater treatment plants (WWTPs) are unable to completely remove antibiotics and microplastics (MPs), resulting in the discharge of residual antibiotics and MPs into the environment, which poses threats to both ecological and human health. Therefore, targeted removal of residual antibiotics and MPs in effluent from WWTPs is crucial. Moreover, the presence of MPs in the wastewater system is likely to affect the removal of antibiotics. Here, the impact of polystyrene (PS) on the sorption characteristics and mechanisms of enrofloxacin (ENR) by hyper-cross-linked polymers (HCPs) was studied. The possibility of collaborative treatment of antibiotics and MPs was also discussed. The results showed that PS could affect the sorption of ENR by interacting with HCPs. The addition of PS increased dispersibility of HCPs and the number of sorption sites, thereby enhancing the sorption of ENR. However, as the concentration of PS increased, the repulsive energy between HCPs and PS decreased from 600 to 280 kT, leading to further heterogeneous aggregation between HCPs and PS. It prevented some of the sorption sites from being exposed to ENR, thereby reducing the promotion effect from 57% to 13%. Additionally, PS facilitated the sorption of ENR through promoting electrostatic attraction, π−π, and n−π interactions. The presence of PS also enhanced the removal of ENR in actual water samples with the efficiency of 98.2%. While removing antibiotics, MPs can also be separated from sewage by forming aggregates with HCPs. This study contributes to a deeper understanding of the role of MPs in the treatment of antibiotics within wastewater systems and offers new insights for the collaborative treatment of emerging contaminants in wastewater systems.

Colloidal interactions for a polystyrene particle and a smooth silicon surface: Atomic force microscopy, XDLVO theory, and Surface Element Integration

In this study Liftshitz van der Waals, electrostatic and acid base interaction forces of a 4 µm polystyrene particle with flat silicon surfaces were experimentally determined using interfacial interaction energy measurements and atomic force microscopy (AFM). Interfacial forces computed using analytical expressions based on the Surface Element Integration (SEI) technique were compared with the standard Derjaguin Approximation (DA) and Continuum Mechanics Adhesion approaches, namely: Derjaguin, Muller and Toporov (DMT), Johnson, Kendall and Roberts (JKR) and Maugis and Pollock (MP) theories in order to assess the effect of curvature on a sphere-plate geometry. For acid base interactions, the SEI was found to deviate from the DA at small particles radii (less than 100 nm) and over a wide ratio of decay length, λ, to particle size, R. Accounting for curvature for acid base interaction requires geometric factors that are functions of λ/R. For van der Waals force of interaction, the SEI and DA showed large variation at large ratios of interparticle separation, D, to particle radius, R. For Double layer interaction force large variation between SEI and DA was observed for small κa values, and good agreement observed at large κa values. The AFM forces of adhesion of polystyrene in 0.01 mM and 100 mM KCl electrolyte solutions were found to be 2.38 ± 2.15 nN and 9.29 ± 6.89 nN, respectively. These results were found to be consistent with the SEI technique that gave adhesion forces of 4.8 and 10.2 nN at the low and high electrolyte concentrations, respectively. These data are also aligned with Maugis and Pollock (MP) theory that accounts for elasto-plastic deformation, Pe.

Effect of molecular weight distribution on the thermal adhesion of polystyrene and PMMA brushes

The effect of the molecular weight distribution (MWD) and graft density of polymer brushes on the adhesion strength of flat substrates was investigated using polystyrene (PS) and poly(methyl methacrylate) (PMMA) brushes with variations in the molecular weight, MWD, and graft density. Two silicon wafers covered with polymer brushes were bound in a 0.5 cm2 contact area using 5 μL of toluene and a pinchcock Hoffman clamp and then annealed at 408 K in a vacuum oven for 3 h. PS brushes with a MWD narrower than Mw/Mn = 1.20 yielded an adhesion strength lower than 0.1 MPa. In contrast, PS brushes having a broad MWD (Mw/Mn = 1.3–1.4) were successfully joined to afford a lap shear adhesion strength of 1.2 MPa despite high graft density due to the intermixing of longer chains of the opposite brushes. Similar results were also obtained in the case of PMMA brush.

Polydopamine surface functionalization of 3D printed resin material for enhanced polystyrene adhesion towards insulation layers for 3D microelectrode arrays (3D MEAs).

3D printing involves the use of photopolymerizable resins, which are toxic and typically have incompatible properties with materials such as polystyrene (PS), which present limitations for biomedical applications. We present a method to dramatically improve the poor adhesion between the PS insulative layer on 3D printed Microelectrode Array (MEA) substrates by functionalizing the resin surface with polydopamine (PDA), a mussel-inspired surface chemistry derivative. A commercial 3D printing prepolymer resin, FormLabs Clear (FLC), was printed using a digital light processing (DLP) printer and then surface functionalized with PDA by alkali-induced aqueous immersion deposition and self-polymerization. It was observed that the adhesion of the PS to FLC was improved due to the precision emanating from the DLP method and further improved after the functionalization of DLP printed substrates with PDA at 1, 12, and 24 h time intervals. The adhesion of PS was evaluated through scotch tape peel testing and instron measurements of planar substrates and incubation testing with qualitative analysis of printed culture wells. The composition and topology of the samples were studied to understand how the properties of the surface change after PDA functionalization and how this contributes to the overall improvement in PS adhesion. Furthermore, the surface energies at each PDA deposition time were calculated from contact angle studies as it related to adhesion. Finally, biocompatibility assays of the newly modified surfaces were performed using mouse cardiac cells (HL-1) to demonstrate the biocompatibility of the PDA functionalization process. PDA surface functionalization of 3D DLP printed FLC resin resulted in a dramatic improvement of thin film PS adhesion and proved to be a biocompatible solution for improving additive manufacturing processes to realize biosensors such as in vitro MEAs.

In Vitro Reconstitution of Spatial Cell Contact Patterns with Isolated Caenorhabditis elegans Embryo Blastomeres and Adhesive Polystyrene Beads.

In multicellular systems, individual cells are surrounded by the various physical and chemical cues coming from neighboring cells and the environment. This tissue complexity confounds the identification of causal link between extrinsic cues and cellular dynamics. A synthetically reconstituted multicellular system overcomes this problem by enabling researchers to test for a specific cue while eliminating others. Here, we present a method to reconstitute cell contact patterns with isolated Caenorhabditis elegans blastomere and adhesive polystyrene beads. The procedures involve eggshell removal, blastomere isolation by disrupting cell-cell adhesion, preparation of adhesive polystyrene beads, and reconstitution of cell-cell or cell-bead contact. Finally, we present the application of this method to investigate the orientation of cellular division axes that contributes to the regulation of spatial cellular patterning and cell fate specification in developing embryos. This robust, reproducible, and versatile in vitro method enables the study of direct relationships between spatial cell contact patterns and cellular responses.

Effect of Durable Superhydrophobic FS/PS Using DCTES on Carbon Steel

Durable superhydrophobic surface on metal substrates was fabricated using very applicable method. The fabrication method aimed to decrease surface free energy and increase surface roughness at same time the process have been accomplished via the addition of silica nano particles with Dodecyltrimethoxysilane (DCTES) bonded to the surface of the silica particles. Adhesive polystyrene was added to improve bond between substrate and functionalized silica. The method is cheap, promising to be applied in factories heat exchangers to reduce fouling and corrosion on the large industrial scale. Scanning electron microscopy (SEM) was used for surface morphology analysis, showing the roughness produced by surface treatment. The wettability of the micro-nano silica film varied from hydrophilicity (water contact angle 88°) to superhydrophobicity (water contact angle 165.2°), while sliding contact angles dramatically decreased (<4°) by adding Functionalized silica and/or adhesive polymer. Roughness increased with silica increment which improves the wettability. The coatings were electrochemically characterized by electrochemical impedance spectroscopy (EIS) and Tafel polarization curves; it was found that both systems had good performance against corrosion in 3.5% sodium chloride solution.

UHV AFM based colloidal probe studies of adhesive properties of VAlN hard coatings

Abstract The adhesion of polystyrene (PS) on V0.27Al0.29N0.44 and the related influence of the oxidation states of both surfaces was investigated using X-Ray Photoelectron Spectroscopy (XPS) and Colloidal Force Spectroscopy (CFS) in Ultra-High Vacuum (UHV). Complementary, the intimate relation between the adhesion force, the chemical structure and surface polarizability was investigated by XPS valence band spectroscopy and the calculation of non-retarded Hamaker coefficients using Lifshitz theory based on optical data as derived from Reflection Electron Energy Loss Spectroscopy (REELS) spectra. The combined electron and force spectroscopic analysis of the interaction forces disclosed quantitatively the separation of the adhesion force in van der Waals and Lewis acid-base contributions. Further, the surface polarizability of VAlN was shown to be unaffected by oxygen incorporation due to the formation of an only gradually oxidized surface comprising a range of vanadium oxidation states. In contrast, the adhesion force analysis revealed additional Lewis acid-base interactions between the oxidized and non-oxidized VAlN surfaces and carboxyl groups present in the surface of PS after an oxidative oxygen beam treatment.

Study on the Combustion Characteristic of Adhesive Polystyrene

In this paper, two kinds of adhesive polystyrene with different proportions and one retardant polystyrene board were studied by test of non combustibility, calorific value and single combustion test. By analysis and comparison, on the premise of the roughly same cost and thermal conductivity, adhesive polystyrene materials showed much less fire risk than that of the polystyrene board.

Ploidy-regulated variation in biofilm-related phenotypes in natural isolates of Saccharomyces cerevisiae.

The ability of yeast to form biofilms contributes to better survival under stressful conditions. We see the impact of yeast biofilms and “flocs” (clumps) in human health and industry, where forming clumps enables yeast to act as a natural filter in brewing and forming biofilms enables yeast to remain virulent in cases of fungal infection. Despite the importance of biofilms in yeast natural isolates, the majority of our knowledge about yeast biofilm genetics comes from work with a few tractable laboratory strains. A new collection of sequenced natural isolates from the Saccharomyces Genome Resequencing Project enabled us to examine the breadth of biofilm-related phenotypes in geographically, ecologically, and genetically diverse strains of Saccharomyces cerevisiae. We present a panel of 31 haploid and 24 diploid strains for which we have characterized six biofilm-related phenotypes: complex colony morphology, complex mat formation, flocculation, agar invasion, polystyrene adhesion, and psuedohyphal growth. Our results show that there is extensive phenotypic variation between and within strains, and that these six phenotypes are primarily uncorrelated or weakly correlated, with the notable exception of complex colony and complex mat formation. We also show that the phenotypic strength of these strains varies significantly depending on ploidy, and the diploid strains demonstrate both decreased and increased phenotypic strength with respect to their haploid counterparts. This is a more complex view of the impact of ploidy on biofilm-related phenotypes than previous work with laboratory strains has suggested, demonstrating the importance and enormous potential of working with natural isolates of yeast.

Experimental Study of the Heat Flux Effect on Combustion Characteristics of Commonly Exterior Thermal Insulation Materials

For the sake of examining the heat flux effect on combustion characteristics of commonly exterior thermal insulation materials, the six kinds of exterior thermal insulation materials were tested by the cone calorimeter in this paper included rock wool, adhesive polystyrene granule, phenolic resin, EPS, XPS and RPU. The experimental results showed that the fire risk of different thermoplastic insulation materials arrange in descending order was XPS>RPU>EPS> adhesive polystyrene granule> phenolic resin> rock wool; with the increase of radiation intensity, the heat release peak rate of PS increased and the ignition time and the peak time reduced, the heat release peak rate and the peak time points showed inverse proportion; the peak HRR value of B2 RPU is 2 times of B1 RPU and the efficiency of fire retardant of B1 RPU increases by 37.53% compared to B2 RPU.

Adipogenic Differentiation of Individual Mesenchymal Stem Cell on Different Geometric Micropatterns

Micropatterned surfaces are very useful to control cell microenvironment and investigate the physical effects on cell function. In this study, poly(vinyl alcohol) (PVA) micropatterns on polystyrene cell-culture plates were prepared using UV photolithography. Cell adhesive polystyrene geometries of triangle, square, pentagon, hexagon, and circle were surrounded by cell nonadhesive PVA to manipulate cell shapes. These different geometries had the same small surface areas for cell spreading. Human mesenchymal stem cells (MSCs) were cultured on the micropatterned surface, and the effect of cell geometry on adipogenic differentiation was investigated. MSCs adhered to the geometric micropatterns and formed arrays of single cell with different shapes. The distribution patterns of actin filaments were similar among these cell shapes and remolded during adipogenesis. The adipogenic differentiation potential of MSCs was similar on the small size triangular, square, pentagonal, hexagonal, and circular geometries according to lipid vacuoles staining. This simple micropatterning technique using photoreactive molecules will be useful for creating micropatterns of arbitrary design on an organic surface, and cell functions can be directly and systematically compared on a single surface without external factors resulting from separate cell culture and coating method.

The influence of nanoparticles on polystyrene adhesion

The effect of silica nanoparticles on the adhesion of micron-sized polystyrene particles to a mica substrate has been investigated using a centrifuge to both ‘spin-on’ and ‘spin-off’ the polystyrene particles under different centrifuge conditions. In the absence of nanoparticles, the quantity of polystyrene particles removed increased steadily as the spin-off force was increased. The particle roughness and the number of particle–particle contacts were described as being responsible for this gradual removal.When nanoparticles were added, an increase in the overall removal of polystyrene particles under a given centrifugal force was seen, when compared to the water-only data. The greatest effect was observed for the lowest nanoparticle concentrations used. These results suggest that the interactions between nanoparticles and surfaces are complex and need to be studied in greater detail to thoroughly understand the particle detachment process.

Measurement of polyamide and polystyrene adhesion with coated-tip atomic force microscopy

This work presents atomic force microscopy (AFM) measurements of adhesion forces between polyamides, polystyrene and AFM tips coated with the same materials. The polymers employed were polyamide 6 (PA6), PA66, PA12 and polystyrene (PS). All adhesion forces between the various unmodified or modified AFM tips and the polymer surfaces were in the range −1.5 to − 8 nN . The weakest force was observed for an unmodified AFM tip with a PS surface and the strongest was between a PS-coated tip and PS surface. The results point to both the benefits and drawbacks of coated-tip AFM force–distance measurements. Adhesion forces between the two most dissimilar (PA6–PS and PA66–PS) materials were significantly asymmetric, e.g., the forces were different depending on the relative placement of each polymer on the AFM tip or substrate. Materials with similar chemistry and intermolecular interactions yielded forces in close agreement regardless of placement on tip or substrate. Using experimental forces, we calculated the contact radii via four models: Derjaguin, Muller, and Toporov; Johnson, Kendall, and Roberts; parametric tip–force–distance relation; and a square pyramid–flat surface (SPFS) model developed herein. The SPFS model gave the most reasonable contact tip radius estimate. Hamaker constants calculated from the SPFS model using this radius agreed in both magnitude and trends with experiment and Lifshitz theory.

Effects of growth temperature on the adhesion ofPseudomonas aeruginosa ATCC 27853 to polystyrene

The aim of this work has been to analyse the effects of temperature on polystyrene adhesion ofPseudomonas aeruginosa ATCC 27853. The bacterial adhesion (expressed as percentage of hydrophobicity) has been measured during the cultivation of this strain at different temperature of growth (15, 30 and 47°C). Data obtained showed that an increase in temperature is a factor that increasing the virulence of the strain in terms of adhesion to polystyrene surfaces. This kind of experiments surely brings important information concerning the prevention of nosocomial infection.

Effects of growth temperature on polystyrene adhesion of Pseudomonas aeruginosa ATCC 27853

The importance of avoiding bacterial adhesion to plastic medical devices is recognized. To better understand the interaction between bacteria and surface, we studied the influence of different growth temperatures (15, 30 and 47oC) on the polystyrene adhesion capacity of Pseudomonas aeruginosa ATCC 27853.

New HYFLON AD composite membranes and AFM characterization

HYFLON AD membranes are very interesting devices in water treatment and for their impermeability to water and gases and vapour transpirability [1]. In these kinds of processes, such in many large-scale processes, some membrane parameters are particularly important, among them: pore distribution, membrane morphology and their fouling tendency. The aim of the present work is to describe an AFM study of three different composite HYFLON AD 60X membranes characterising three key properties affecting performance: pore size distribution, surface morphology and particle adhesion. The membranes have been imaged at high resolution in NaCl solution, allowing quantification of surface roughness and pore size distribution. Further, the adhesion of polystyrene and silica particles to the membranes was measured in NaCl solution at three different concentrations to quantify their likely fouling tendencies.

The influence of surface topography in the adhesion of polystyrene to aluminum

Polymer/metal adhesion has been studied by scanning(SEM) and transmission electron microscopy(TEM). Now with atomic force microscopy(AFM) we can scan the metal's surface and correlate the roughness with adhesion energy. We have chosen aluminum as the metal substrate and polystyrene(PS) as the nonreactive polymer adhesive. A great deal of research has been done on primed metal surfaces which are used to improve adhesion between the metal and the polymer. Our interest is to study the mechanical interlocking of the polymer to the metal without a primer coupling agent.Aluminum alloy 6061 was cut into plates 25x60x1 mm, cleaned with an alkali cleaner, rinsed with water, etched and anodized. The plates were etched in a solution of Na2Cr2O7·2H2O, H2SO4, and water in a 1:10:30 ratio by weight at 50-52°C for 12-20 min. After etching , they were rinsed, dried and anodized in 10% phosphoric acid solution with 15 V for 20 min, then were rinsed and dried again.A 1% PS solution in toluene was deposited on the prepared aluminum surface and air dried.

Identification ofLactobacillusStrains Isolated from Patients with Infective Endocardi tis and Comparison of their Surface-associated Properties with those of Other Strains of the Same Species

Ten strains of lactobacilli isolated from infective endocarditis (IE) cases were speciated using the API 50CHL identification system and the identify computer program, and shown to be either Lactobacillus rhamnosus (five strains) or L. paracasei subsp. paracasei strains (five strains). A comparison of their adhesive and surface-associated properties with 14 strains (seven each from the same two species) isolated from other sources indicated that the IE strains showed a significantly greater aggregation by saliva ( P= 0.005) and a significantly increased binding of fibronectin at pH 5-4. When the two species were compared, the IE L. rhamnosus group of strains had significantly higher values for hydrophobicity, hydroxyapatite adhesion (HA) and salivary aggregation (P<0.05) than the laboratory strains, whereas none of the assays were significantly different for the IE L. paracasei subsp. paracasei strains. Fibronectin binding was significantly increased for both species when the pH was reduced from 7.3 to 5.4. Fibronectin binding at pH 5.4 was correlated with the cell surface charge, while polystyrene adhesion was correlated with both hydrophobicity and HA adhesion. The data indicated that there may be a contributory role for surface-associated properties in the pathogenesis of Lactobacillus endocarditis, and that strains isolated from IE patients, particularly L. rhamnosus , differ in important respects (hydrophobicity, salivary aggregation and HA adhesion) from most other strains of the same species. Keywords - Adhesion, Hydrophobicity, Salivary aggregation, Fibronectin, pH, Endocarditis, Lactobacillus paracasei, L. rhamnosus .

The adhesion of polystyrene to wood

This article gives a review of certain concepts of adhesion and reports some experimental results. The main conclusions are as follows: The adhesion of polystyrene to wood is in about 60% the effect of dispersion forces and in the rest of polar forces. The non compensated polar forces of the wood substrate causes a surface tension on the wood-polystyrene interface. The weakest link in the wood-polystyrene system is the polystyrene and not the wood-polystyrene interface. A great influence on the “practical” adhesion measured by a pull-off test has the contraction of polystyrene during the thermocatalytic polymerization and involved shrinkage stresses which cause cavitation in polystyrene.

The adhesion of polystyrene to wood

The adhesion of polystyrene to wood