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Eco-friendly, nontoxic and high-energy storage materials are very important for flexible electrode materials. Bi₄Ti₃${\text{O}}_{12}$ lead-free, perovskite phase may prove suitable as filler in composites for electrode materials because of its large spontaneous polarization. We have synthesized Bi₄Ti₃${\text{O}}_{12}$/polystyrene (BTO/PS) composites and carried out their structural, morphological and bonding studies with the help of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), in that order. Dielectric measurements in the broad frequency range of synthesized composites determined by Impedance analyzer. We observed that the dielectric constant of composites increased with filler concentration and decreased with applied field frequency. Bi₄Ti₃${\text{O}}_{12}$/PS composites can be good electrode materials.

Polystyrene (PS) is a common substrate material for protein adsorption on biosensors and bioassays. By employing a quartz crystal microbalance (QCM) technique, we studied the kinetics and thermodynamics of anti-HBeAg adsorption on this substrate in situ. First, a thin PS film was deposited on the interface between the liquid and the quartz crystal wafer. Second, a solution containing anti-HBeAg was introduced into the holding tank. Third, we measured the change in the oscillation frequency of the quartz that was induced by the antibody–PS binding, which in turn depended on macroscopic parameters, such as antibody concentration and solution temperature, as well as on microscopic parameters, such as the diffusion type and the change in Gibb's free energy. The adsorption rate and capacity of anti-HBeAg on the PS surface were quantified and fitted using the conventional Langmuir model. It was shown that this model was applicable to protein–PS interface system. Approximately 250 nm² of the surface area was occupied by a single antibody molecule at 298 K when the concentration was 90 μg/mL. The adsorption process might have been controlled by both liquid film and particle diffusions.

Spin coating has been widely used for obtaining uniform thin polymeric coating over glass surfaces. Previous studies have shown that the thin-coated film can deform and bulge out upon immersion in liquid. Such deformations can affect various properties of the films. In this study, we have analyzed the interaction of glass colloidal particle and the polystyrene (PS) spin-coated surface immersed in deionized (DI) water. It was found that the glass colloidal particle interacts with the surface in dissimilar way at various locations on the surface. A sudden reduction in the forces was also observed at different locations on the same surface. The separation distances at which the sudden change in the force occurred was closer to the height of the spherical domains. Therefore, the change could be attributed to the presence of blisters on the surface formed due to permeation of water into the thin film-substrate interface.

Carbon nanotubes were functionalized by polystyrene copolymers, poly(styrene-co-hydroxymethylstyrene) and poly(styrene-co-aminomethylstyrene), under esterification and amidation reaction conditions, respectively. The polymer-attached carbon nanotubes are soluble in common organic solvents, forming colored homogeneous solutions. Results from the characterization of the functionalized carbon nanotubes are presented and discussed.

This paper reported fluorescent labels which were made by encapsulating quantum dots (QDs) in polystyrene nanoparticles with carboxyl groups and used to stain cells. The fluorescent capsules were characterized by TEM and FTIR and the stained cells were studied under laser scanning confocal microscope.

Two multi-nuclear titanium complexes [Ti(η⁵–Cp*)Cl(μ–O)]₃(1) and [(η⁵–Cp*TiCl)(μ–O)₂(η⁵–Cp*Ti)₂(μ–O)(μ–O)₂]₂Ti (Cp* = C₅Me₅)(2) have been investigated as the precatalysts for syndiospecific polymerization of styrene. In the presence of modified methylaluminoxane (MMAO) as a cocatalyst, complexes 1 and 2 display much higher catalytic activities towards styrene polymerization, and produce the higher molecular weight polystyrenes with higher syndiotacticities and melting temperatures (T_m) than the mother complex Cp*TiCl₃ does when the polymerization temperature is above 70°C and the Al/Ti molar ratio is in the low range especially.

In this paper two different kinds of dynamic mechanical techniques (inversed torsion pendulum and energy dissipation apparatus) were used to study the dynamic behavior of atactic monodisperse polystyrene above glass transition. The plots of energy dissipation versus temperature were presented for two atactic polystyrene samples. An apparent energy dissipation peak occurred above T_g in each plot measured by the inversed torsion pendulum, and simultaneously the sample was found to flow assuredly at the moment. To exclude the influence of the flow and demonstrate there was a peak indeed above T_g, the energy dissipation apparatus was used, in which the samples were put into a cup. An obvious peak appeared, and it was in agreement with the peak observed by the inversed torsion pendulum. On basis of the results measured by the two kinds of apparatus, a conclusion is drawn that a peak occurrs above T_g, which gives a manifestation for the existence of the liquid-liquid transition.

A study has been conducted on the synthesis and characterization of a kind of novel polyrotaxanes comprising α-cyclodextrins (α-CDs) threaded on triblock copolymers with poly(ethylene glycol) (PEG) as a central axle and flanked by two low molecular weight polystyrenes as outer stoppers. Styrene was allowed to telomerize with polypseudorotaxanes as chain transfer agents made from the self-assembly of a distal thiol-capped PEG with a varying amount of α-CDs in the presence of a redox initiation system at 40°C in aqueous solutions. The resulting polyrotaxanes were characterized in detail by ¹H-NMR, FTIR, XRD, TG and DSC analyses. The findings from the study demonstrated that the low molecular weight polystyrenes were successfully attached to two axle terminals of polypseudorotaxanes, and the number of α-CDs threaded onto the PEG backbone was tunable by varying its molar feeding ratio to some extent, while the polymerization degree of PS nearly remained constant in this radical telomerization process.

The typical immiscible PP/PS blend based clay nanocomposites were prepared via melt blending. The dispersion of clay was determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thermal stability and dynamic mechanical properties were measured by thermogravimetrical analysis (TGA) and dynamic mechanical analysis (DMA), respectively. Preferential intercalation behavior of clay in PP/PS blends was found. The dispersion of clay is significantly influenced by the polarity of PP and PS, meanwhile the location of clay can be controlled by the alternation of the polarity of PP and PS through chemical modification. The clay migrates from PS phase to PP phase with the improvement of the polarity of PP. However, when the PS is sulfonated, clay migrates back to the dispersed PS phase again. The dispersion and location of clay have profound influence on the thermal and dynamic mechanical behavior of PP/PS blends. The better the dispersion of clay in either continuous phase or disperse phase, the higher the thermal stability of the blends. Besides, samples with clay located in the continuous phase can display the best strengthening effect.

A series of titanium complexes Ar[O, E]Cp*TiCl (Cp* = C₅Me₅, Ar = 1,2-phenylene, E = NH (1a); Ar = 1,2-phenylene, E = O (1b); Ar = 2,2′-diphenylene, E = O (1c); Ar = 2,2′-dinaphthalene, E = O (1d)) has been prepared by the reaction of corresponding phenol derivatives with Cp*TiCl₃ in the presence of excessive triethylamine. Under the conditions of low Al/Ti molar ratio (e.g. 500) and high reaction temperatures (≥ 70°C), all the titanium complexes display higher catalytic activities towards the syndiospecific polymerization of styrene, in the presence of modified methylaluminoxane (MMAO) as a cocatalyst, than their mother complex Cp*TiCl₃. The catalyst activities and polymer yields as well as polymer properties are considerably affected by the steric and electronical effects of the bidentate ligands.

Effect of pristine and modified MCM-41 on the kinetics of styrene atom transfer radical polymerization (ATRP) was studied using a double bound containing modifier at 110°C. Conversion, molecular weight and PDI were obtained during the polymerization reactions to study the polymerization kinetics. Addition of the both types of MCM-41 has resulted in inconsiderable variations on the kinetics of polymerization. A similar trend is observed for the molecular weight of the free chains; however, increasing MCM-41 content results in higher PDI values. Also, surface modification of MCM-41 results in lower polymerization rates. In the case of grafted chains, molecular weight and PDI values increase by increasing MCM-41 content.

Mesoporous silica nanoparticles (MCM-41) surface was functionalized with 3-(trimethoxysilyl)propyl methacrylate (MPS). Then, the resultant double bond containing nanoparticles were used in grafting through simultaneous reverse and normal initiation technique for atom transfer radical polymerization (SR&NI ATRP) of styrene to synthesize well-defined polystyrene nanocomposites with twofold chains. Nitrogen adsorption/desorption isotherm and X-ray diffraction analysis were used to evaluate characteristics of spherical MCM-41 nanoparticles. Morphological studies were also performed by scanning and transmission electron microscopy. Conversion and molecular weight determinations were carried out using gas and size exclusion chromatography respectively. Addition of MCM-41 nanoparticles by 3 wt.% results in a decrease of conversion from 93% to 82%. Molecular weight of the free and attached polystyrene chains decreases by adding 3 wt.% MCM-41 nanoparticles; however, PDI values increases from 1.27 to 1.78 for free chains and 1.87 to 2.48 for attached chains. A peak around 4.1 ppm which originates from hydrogen atom of terminal units of polystyrene chains in proton nuclear magnetic resonance spectra in combination with low PDI values can appropriately demonstrate the living nature of the polymerization. Increasing thermal stability of the nanocomposites is demonstrated by Thermogravimetric analysis. Differential scanning calorimetry also shows a decrease in glass transition temperature by increasing MCM-41 nanoparticles.

In this study, the modified polystyrene aldehyde microspheres (PS-CHO) were first prepared via the copolymerization of the styrene and the acrolein, and then PS-CHO@CeO₂ composite microspheres were fabricated through in-situ chemical deposition of CeO₂ nanoparticles. These composite microspheres were used to catalyze the oxidative degradation of methyl orange (MO) by H₂O₂. The morphology of the products was observed by transmission electron microscopy (TEM). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the chemical state and structure. Optical absorption and band energy properties were investigated by ultraviolet-visible/near-infrared diffuse reflectance spectra (UV-Vis-NIR). The degradation process was monitored with ultraviolet-visible spectrometer (UV-Vis). The results revealed that when the mass ratio of PS-CHO and cerium nitrate was 1:0.26, highly-uniformed and well-dispersibility PS-CHO@CeO₂ composite microspheres were obtained at pH 8.5 and the concentration of Ce${}^{3+}$ ions was significantly increased compared with commercial CeO₂ NPs. Under ultraviolet light irradiation, the degradation efficiency of MO by PS-CHO@CeO₂ composite microspheres was increased up to 93.03%, which was 1.44 times that of commercial CeO₂ NPs in 120 min. The reiteratively tests further proved that the activity of the composite microspheres maintained unchanged after four cycles. The formation and photocatalytic mechanisms of PS-CHO@CeO₂ composite microspheres were proposed.

Electrospinning represents a simple, cost-effective technique that allows the production of continuous fibers, with diameters ranging from the micrometer to the nanometer scale. Mixing particles in the polymer feed solution could result in composite fibers, with various potential applications, depending on the particle filler. The influence of electrospinning parameters on the fiber morphology must be investigated to obtain undamaged fibers without large agglomerates. This research presents polystyrene (PS)-based electrospun composite fibers, containing the first- and the second-generation Grubbs’ catalyst (G1 and G2). Loading of both catalysts was 1wt.% in the composite fibers, and the influence of different solution flow rates on fiber diameter, shape and regularity was investigated. Applied flow rates were 5, 10, 15 and 20ml/h for both composites (PS-G1 and PS-G2). Software analysis of field emission scanning electron microscopy (FESEM) images has revealed that flow rate has a higher influence on the diameter increase in PS-G1 compared to PS-G2, due to a difference in electrostatic forces and polymer-catalyst interactions. In both composites, 10ml/h was the threshold for producing smooth and undamaged fibers, further enhanced in PS-G2, where large agglomerates were observed at 20ml/h. Furthermore, in both composites, fiber diameter distribution was significantly wider at higher flow rates, which is not a desirable feature in composites. The presented results demonstrated the synergy between different parameters that influence the formation and morphology of electrospun PS-based composites and could help in the future design and processing of continuous composite fibers.

In this study, the effects of nanoclay content on compatibility of Polylactide(PLA)/Polystyrene(PS) blends were investigated. The PLA/PS blends and their nanoclay composites were prepared through a twin-screw extruder. Thermogravimetric analysis(TGA) and differential scanning calorimetry(DSC) were performed to study the thermal properties of blends and their nanocomposites. Scanning electron microscopy (SEM) was employed to study the miscibility of PLA/PS blends on the presence of nanoclay. The research results showed that with an addition of appropriate amount of nanoclay, the compatibility of PLA/PS blends could be significantly increased.

Unvulcanized polar graft-modified rubbers, including maleic anhydride grafted ethylene propylene diene monomer (MAH-g-EPDM) and 49% methyl methacrylate grafted natural rubber (MMA-g-NR, i.e. MG49 rubber), were empolyed to toughen polystyrene (PS). The results showed that Charpy impact strength of the unnotched PS specimens at room temperature was improved by addition of the graft-modified rubbers. Moreover, Charpy impact strength of the composite increased with increasing content of polar graft-modified rubbers in this study, and the incorporation of MAH-g-EPDM enhanced impact strength of PS more markedly than that of MG49 did. The result of thermogravimetric analysis (TGA) indicated that the addition of MAH-g-EPDM improved the thermal stability of PS, while the incorporation of MG49 reduced it. The result of thermal mechanical analysis (TMA) indicated that the glass transition temperatures of their corresponding PS-based blends increased with the addition of either MAH-g-EPDM or MG49. The glass transition temperatures of PS-based blends increased with increasing polar graft-modified rubbers content. This may be due to the incorporation of the polar grafts. This work may also provide some information for oil-resistant modification of PS due to the polar groups grafted onto the backbone of rubbers.