Suspension Polymerization Of Styrene Research Articles

Preparation of functionalizable poly(propylene–styrene)/polyacrylonitrile millimeter‐scale particles with core‐shell morphology

AbstractCore‐Shell (CS) polymeric particles have attracted great interest due to their high mechanical, thermal, and chemical stability and their surface properties. In this study, functionalizable CS poly(propylene/styrene)/poly(acrylonitrile) (PP/PS/PAN) particles were prepared through heterogeneous polymerizations in a batch reactor. Commercial PP particles and PP/PS particles (prepared by seeded suspension polymerization of styrene (Sty) on PP spheres) were applied as core components of the final structure, while the shell was prepared through acrylonitrile dispersion polymerization. The degree of swelling of the core particles by Sty played an important role for the adhesion of the PAN shell, which for PP particles was 24 wt%, whereas for PP/PS hybrid particles it was 57 wt%. The particles (PP/PS and CS) were characterized through image analysis, revealing a uniform and smooth surface for PP/PS spheres and a uniform porous shell for CS particles. Particle size distributions, thermal degradation, chemical structures, degrees of crystallinity, and textural properties were also evaluated. The PAN shell adhered to the PP/PS particles without forming a copolymer, and the CS particles formed by a PP/PS core and PAN shell had sizes of 4.54 ± 1.24 mm, specific area of 2.70 m2g−1 and PAN content of 15.98 ± 0.82% (m/m) of total particles.

АНАЛИЗ ПРОЦЕССА СУСПЕНЗИОННОЙ ПОЛИМЕРИЗАЦИИ СТИРОЛА В ПЕРИОДИЧЕСКОМ РЕАКТОРЕ С МЕШАЛКОЙ КАК ОБЪЕКТА УПРАВЛЕНИЯ

A schematic diagram of the suspension polymerization of styrene in a periodic reactor with a stirrer is presented, the stages of the polymerization process are listed, and the process as an object of con-trol is analyzed

КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ СУСПЕНЗИОННОЙ ПОЛИМЕРИЗАЦИИ СТИРОЛА В ПЕРИОДИЧЕСКОМ РЕАКТОРЕ С МЕШАЛКОЙ

A mathematical model of the process of suspension polymerization of styrene in a periodic reactor with a stirrer and the results of computer simulation of the process are presented

The Use of the Computer Tomography Method in the Analysis of the Microstructure of Materials Formed as a Result of Hydrothermal Treatment: Cellular Concretes

The subject of this research is sustainable construction and energy saving, which is most reflected in the technological aspects of building construction. This article focuses on single-family buildings, and the subject of this research is hollow blocks (blocks) created as a result of hydrothermal treatment, in this case, autoclaved aerated concrete (AAC) and autoclaved cellular concrete (ACC), both traditional and modified plastics (HIPS). There are two types of materials resulting from hydrothermal treatment: autoclaved sand-lime bricks and autoclaved concrete. Both in the case of ACC and silicates bricks, the basic substrates used during their production are lime, sand and water (cement is also added to cellular concrete). This article presents the methodology of testing the porous structure of autoclaved materials with the use of computed tomography. Aerated concrete (light autoclaved concrete) has a compressive strength of 2–6 MPa. The tests included aerated concrete modified with high-impact polystyrene, commonly known as HIPS. HIPS high-impact polystyrene is a thermoplastic polymer that is obtained by block suspension polymerization of styrene with the addition of synthetic rubber. As a result of polymerization, small particles of polybutadiene remain in the polystyrene male, changing its physical and mechanical properties. The results from the content of air voids in the autoclaved concrete sample were, on average, 52.53%.

Synthesis and Physico-mechanical Characterization of Polystyrene Blended with Uvaria chamae Seed Oil (UCSO) Used as a Plasticizer

Polystyrene has long been recognized as a versatile and cost-effective material used in several industries, such as packaging, consumer electronics, building, medical, and and food service disposables. The current research focuses on the synthesis and physico-mechanical characterization of polystyrene blended with Uvaria chamae seed oil (UCSO), used as a plasticizer. UCSO was extracted with hexane and used as a plasticizer in the suspension polymerization of styrene. The findings on the quality of the oil are as follows: oil content (12.54%), specific gravity at 25 oC (0.94 ± 0.00), acid value (8.029 ± 0.12 mg KOH), iodine value (18.987 ± 0.40), peroxide value (7.0), free fatty acid (4.015%), and saponification values (173.392). The mechanical properties of the polystyrene blend with Uvaria chamae seed oil (PS-UCSO) at 100g were reported as follows: ultimate tensile strength (48.6 MPa), Young modulus (1985.3 MPa), % elongation (12.6%), break load (390.6 N), peak load (386.5 N), Shore D hardness (80.0), and water absorption (1.31%). Other properties like thermal conductivity and thermal resistance were reported as 0.2614 (W/m.K.) and 3.8256 (1/k). The findings revealed that the mechanical properties of PS-UCSO were highly competitive with the conventional white petroleum oil used as a plasticizer. As a recommendation, Uvaria chamae seed oil should be used as a plasticizer since it is available, cheap, and environmentally friendly.

Core@Double-Shell Engineering of Zn Particles toward Elevated Dielectric Properties: Multiple Polarization Mechanisms in Zn@Znch@PS/PVDF Composites.

Flexible dielectrics with large dielectric constant (ε') coupled with low loss are highly pursued in many applications. To bolster the ε' of raw Zn (zinc)/poly(vinylidene fluoride, PVDF) while maintaining pimping dielectric loss, in this study, the core@double-shell structured Zn@zinc carbonate (ZnCH)@polystyrene (PS) particles are first synthesized through a suspension polymerization of styrene, and then composited with PVDF to elevate the ε' and keep low loss of the composites. By optimizing the PS shells' thickness and tailoring the electrical resistivity of Zn@ZnCH@PS particles, both the slow inter-particle polarization and fast intra-particle polarization in the composites can be decoupled and synergistically tuned, thus, the Zn@ZnCH@PS/PVDF achieves a much higher ε' and lower dielectric loss, simultaneously, which far exceed the unmodified Zn/PVDF. Both experiment and theoretic calculation reveal that the double-shell ZnCH@PS not only induces and promotes multiple polarizations enhancing the composites' ε', especially at the optimized PS's thickness, but also maintains suppressed loss and conductivity thanks to their obvious barrier effect on long-range charge migration. The core@double-shell filler design strategy facilitates the development of polymer composites with desirable dielectric properties for applications in electronic and electrical power systems.

Investigation on the Controllable Synthesis of Colorized and Magnetic Polystyrene Beads With Millimeter Size via In Situ Suspension Polymerization

A series of colorized and magnetic polystyrene/Fe3O4 (PS/Fe3O4) composite beads with millimeter size are successfully synthesized by introducing hydrophobic Fe3O4 via in situ suspension polymerization of styrene for the first time. Effects of the hydrophobic Fe3O4 content, stirring speed, and surfactant dosage on the macromorphology and particle size of PS/Fe3O4 beads are systematically investigated to realize the controllable synthesis. Moreover, three kinds of hydrophobic pigments are also employed to synthesize colorized polystyrene, which demonstrates the versatility, simplicity, and wide applicability of the proposed method. Scanning electron microscopy (SEM) and element mapping (EM) images demonstrated that the hydrophobic Fe3O4 is well dispersed in the polystyrene matrix. Thermogravimetric analysis (TGA) shows that the resultant PS/Fe3O4 beads possess a better thermal stability than neat PS. PS/Fe3O4 beads have a promising application in the fields of colorized extruded PS board, colorized expanded PS foam particle, and board.

Study and Analysis of the Change in the Viscosity of a Reaction Mixture during the Suspension Polymerization of Styrene

Study and Analysis of the Change in the Viscosity of a Reaction Mixture during the Suspension Polymerization of Styrene

Study on preparation and process of poly(MMA‐St) thermally expandablecore‐shellmicrospheres

AbstractThermally expandable microspheres were synthesized by the suspension polymerization of methyl methacrylate (MMA) and styrene (St) in the presence of paraffin blowing agents. The effect of the monomer composition, the initiator, the blowing agent, the polymerization temperature on the morphology and structure of microspheres were studied. The results showed that AIBN initiated the water phase polymerization of MMA to form secondary polymer particles adsorbed on the surface of the microspheres. MMA diffused from the oil phase to the water phase, which accelerated the phase separation and facilitated the formation of core‐shell microspheres. However, LPO could not initiate the water phase polymerization, the phase separation was slow and there was an intermediate state with a porous surface. When the boiling point of the blowing agent was lower than the polymerization temperature, the microspheres were porous and there were a large number of holes on the surface.

Reactor Dynamics of Suspension Polymerization of Styrene

The reactor dynamics of suspension polymerization of styrene has been studied in a specially designed unit controlled by a computer. It is found that the changes under control actions (measure of heating power and measure of stirrer shaft power) consistently describe the changes in the physical (relaxation) state of polymer–monomer particles. This phenomenon is proposed to be used to control the process.

Expandable polystyrene without any embedded blowing agent

In this research, in-situ suspension polymerization of styrene in the presence of graphene, without any blowing agent, was investigated. Steam used in the expansion process of graphene-filled expandable polystyrene (GEPS). The dispersed graphene nano-sheets in the polystyrene matrix may absorb water in high temperatures, which evaporates by lowering the pressure and expansion precedes. The effects of graphene type and loading and steam temperature on the expansion ratio evaluated. Scanning electron microscopy (SEM) used to reveal the cross-section morphologies before and after expansion. The effect of graphene on the polymerization kinetics evaluated by differential scanning calorimetry (DSC). The results showed that by increasing the graphene loading, the rate of polymerization decreased, and the expansion ratio increased. The highest expansion ratio of about 4.8 was for particles containing 0.4% of graphene. Therefore, it was shown that by using graphene as a dispersed phase, polystyrene particles expanded without any organic blowing agents. Here, the idea of expandable polymers without any embedded blowing agent is introduced, which eliminates the release of volatile organic compounds and makes the process environmentally friendly.

The Role of Reduced Graphene Oxide in the Suspension Polymerization of Styrene and Its Effect on the Morphology and Thermal Properties of the Polystyrene/rGO Nanocomposites.

Reduced graphene oxide (rGO) was used to obtain Polystyrene (PS)/rGO nanocomposites via in-situ suspension polymerization. The main goal of the article was to determine how rGO influences the morphology and thermal properties of PS beads. The obtained samples were studied by means of a scanning electron microscope (SEM), and calorimetric and thermogravimetric analysis (DCS, TGA). It was proven that the addition of rGO, due to the presence of polar functional groups, causes significant changes in bead sizes and size distribution, and in their morphology (on the surface and in cross-section). The increasing amount of rGO in the polymer matrix increased the size of beads from 0.36 to 3.17 mm for pure PS and PS with 0.2 wt% rGO content, respectively. PS/rGO nanocomposites are characterized by distinctly improved thermostability, which is primarily expressed in the increase in their decomposition temperature. For a sample containing 0.3 wt% rGO, the difference is more than 12 °C in comparison to pure PS beads.

Preparation and Characterization of Carrot Nanofiber and their Reinforced Nanocomposite Films

In this study, the cellulose nanofiber (CNF) was prepared using carrot slag discarded from industrial carrot juice. The FTIR results of the carrot fiber show that the impurities such as lignin have been removed after alkali and acid neutralization treatment. In addition, it was confirmed that the carrot nanofiber was successfully prepared by the 2,2,6,6-tetramethylpiperidine (TEMPO) radical oxidation method. Subsequently, the obtained nanofiber was surface modified by styrene suspension polymerization and silane coupling agent, respectively. The results of water contact angle analysis show that the hydrophobicity of the modified nanofibers was improved. Moreover, a set of nanocomposite films were prepared by incorporating carrot nanofiber into sodium alginate (SA) and polystyrene (PS), respectively by using solution casting method. The obtained results showed that the TEMPO radical oxidized nanofiber containing film had the best transmittance in SA nanocomposite series. On the other hand, styrene suspension polymerization modified nanofiber containing one exhibited the best transparency in PS nanocomposite series.

ПРОЦЕСС ПОЛИМЕРИЗАЦИИ СТИРОЛА ПОД ДЕЙСТВИЕМ АКУСТИЧЕСКОГО ИЗЛУЧЕНИЯ

Cavitation treatment in the suspension polymerization of styrene leads to an increase in the yield of the finished product

A study on preparation of modified Graphene Oxide and flame retardancy of polystyrene composite microspheres

ABSTRACT In this paper, the ODOPM, a kind of 9, 10-dihydro-9-oxygen-heterooxy-10-phosphoro-10-oxygen (DOPO) derivative, was obtained by hydroxylation of DOPO. Further, a phosphorus nano-flame retardant (GO-ODOPM) was obtained by addition reaction with carboxylated Graphite Oxide (GO-COOH). And then Graphene Oxide/polystyrene (GO-ODOPM/PS) composite microspheres were obtained via suspension polymerization of styrene with GO-ODOPM. The decrease of the peak heat release rate (HRR) and total heat release rate (THR) for the GO-ODOPM/PS composite microspheres was obtained when the content of the additives was only 3.0 wt% is more than 36.2% and 33.6% compared with the pure PS microspheres, respectively. Thermogravimetric (TG), dynamic rheology and carbon residue analysis were used to study the flame-retardant mechanism of GO-ODOPM in PS microspheres. The results revealed that the addition of GO-ODOPM obviously reduced the fire hazard of polystyrene (PS) microspheres. Thus, this work provided a feasible method to design efficient flame retardants for enhancing fire safety of polymers.

Research and analysis of changes in viscosity of reaction mixture during styrene suspension polymerization

Новые технологии, Химическая промышленность, Химическая технология, Научные журналы, Защита от коррозии, Технология металлов, Свойства материалов, Технические журналы, Наука и технологии, Справочная литература, Научные разработки

Phenylglyoxaldehyde-Functionalized Polymeric Sorbents for Urea Removal from Aqueous Solutions.

For realization of a wearable artificial kidney based on regeneration of a small volume of dialysate, efficient urea removal from dialysate is a major challenge. Here a potentially suitable polymeric sorbent based on phenylglyoxaldehyde (PGA), able to covalently bind urea under physiological conditions, is described. Sorbent beads containing PGA groups were obtained by suspension polymerization of either styrene or vinylphenylethan-1-one (VPE), followed by modification of the aromatic groups of poly(styrene) and poly(VPE) into PGA. It was found that PGA-functionalized sorbent beads had maximum urea binding capacities of 1.4–2.2 mmol/g and removed ∼0.6 mmol urea/g in 8 h at 37 °C under static conditions from urea-enriched phosphate-buffered saline, conditions representative of dialysate regeneration. This means that the daily urea production of a dialysis patient can be removed with a few hundred grams of this sorbent which, is an important step forward in the development of a wearable artificial kidney.

Some Reflections On Styrene Suspension Polymerization Experiment Teaching

The results of suspension polymerization of styrene were studied by changing the dosage of initiator, stirring speed, size of stirring paddle, content of dispersant and reaction temperature. The results showed that when using 500 ml four flasks, styrene 40 ml and polyvinyl alcohol solution (3 g polyvinyl alcohol dissolved in 1000 ml deionized water) 200 ml, initiator 0.5 g, stirring speed 300-450 r/min, temperature range 86-95°C, using the stepped heating method and using the impeller with a spreading blade diameter of 43 mm can ensure the success of the experiment, and the yield is relatively high.

Surface modification of carbon black to facilitate suspension polymerization of styrene and carbon black

ABSTRACTTo carry out suspension polymerization of styrene in the presence of carbon black, an effective method was introduced to modify carbon black using nitric acid for oxygen treatment. The surface modification of carbon black with oxidation was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy (SEM), which demonstrated that the chemical structure of carbon black has clearly changed. Compared with pristine carbon black (CB), SEM illustrates that the aggregation phenomenon of modified carbon black (MCB) was clearly weakened. After modification, the aggregation and inhibition effects of MCB on the polymerization of polystyrene/modified CB (PS/MCB) composite particles are obviously weakened. The lipophilicity of CB after modification was also increased during the synthesis of PS/MCB. The oxidized CB was successfully dispersed by polystyrene using in situ suspension polymerization. The dispersion and dosage of MCB in PS/MCB composite particles was greatly improved over that of CB in PS/CB composite particles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46387.

СУСПЕНЗИОННАЯ ПОЛИМЕРИЗАЦИЯ СТИРОЛА В ГЕЛЕ

In this study, a method for the suspension polymerization of styrene in a dispersive gel medium was developed. An aqueous solution of methylcellulose was used as the gel. The dependence of the dynamic viscosity of methylcellulose solutions on temperature was established. The polymerization of styrene was carried out during 2 or 4 hours at a temperature of 60-80 ° C at the gelation point of methylcellulose solu-tions. The ratio of styrene to methylcellulose was 1:10. When the pol-ymer was cooled, solid polymer particles precipitated on the bottom of the vessel and could be easily separated. The particle polymer sizes var-ied from 0.01 to 7 mm.