In the current context of environmental challenges, this study focuses on developing innovative and eco-friendly composites using rice husk and recycled expanded polystyrene. This dual-responsibility approach valorize...In the current context of environmental challenges, this study focuses on developing innovative and eco-friendly composites using rice husk and recycled expanded polystyrene. This dual-responsibility approach valorizes a by-product like rice husk, often considered waste, and reuses polystyrene, a plastic waste, thereby contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene into a solvent to create a binder, which is then mixed with rice husk and cold-compacted into composite materials. The study examines the impact of two particle sizes (fine and coarse) and different proportions of recycled polystyrene binder. The results show significant variations in the mechanical characteristics of the composites, with Modulus of Rupture (MOR) values varying from 2.41 to 3.47 MPa, Modulus of Elasticity (MOE) ranging from 223.41 to 1497.2 MPa, and Stiffness Coefficient (K) from 5.04 to 33.96 N/mm. These characteristics demonstrate that these composites are appropriate for various construction applications, including interior decoration, panel claddings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only highlights the recycling of agricultural and plastic waste but also provides a localized approach to addressing global climate change challenges through the adoption of sustainable building materials.展开更多
Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufac...Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufacturing method that involves dissolving the polystyrene in a solvent followed by cold pressing. Various particle sizes and two binder dosages were investigated to assess their influence on the physico-mechanical properties of the composites. The mechanical properties obtained range from 2.54 to 4.47 MPa for the Modulus of Rupture (MOR) and from 686 to 1400 MPa for the Modulus of Elasticity in Bending (MOE). The results indicate that these composites have potential for applications in the construction sector, particularly for wood structures and interior decoration. Moreover, surface treatments could enhance their durability and mechanical properties. This research contributes to the valorization of agricultural and plastic waste as eco-friendly and economical construction materials.展开更多
Fluorescent polystyrene(PS)/porphyrin(TPPA) composite nanospheres were successfully fabricated by electrospinning. The SEM images clearly show that owing to adding TPPA in PS, the averaged diameter of the composit...Fluorescent polystyrene(PS)/porphyrin(TPPA) composite nanospheres were successfully fabricated by electrospinning. The SEM images clearly show that owing to adding TPPA in PS, the averaged diameter of the composite nanospheres became smaller, from 1500 to 580 nm. Fourier-transform infrared(FTIR) spectra determined the chemical composition of the resulting PS/TPPA composite nanospheres. The photoluminescent(PL) spectral analysis indicates that the peak position of the composite nanospheres in either solid state or water is identical to that of pure TPPA, at about 652 nm, and is still unchangeable when they are left for at least 20 d, indicating the stable photoluminescent property of the fluorescent composite nanospheres.展开更多
Monooctadecyl maleate, as a polymerizable surfactant, was synthesized by the mono-esterification of maleic anhydride and octadecanol, and was utilized to surface-modify nano-Fe3O4 particles. A polymerizable magnetic f...Monooctadecyl maleate, as a polymerizable surfactant, was synthesized by the mono-esterification of maleic anhydride and octadecanol, and was utilized to surface-modify nano-Fe3O4 particles. A polymerizable magnetic fluid was obtained by directly dispersing modified nano-Fe3O4 particles into styrene monomer, and the polystyrene/nano-Fe3O4 composite was prepared through free radical polymerization of polymerizable magnetic fluid. The structure and dispersion status in different dispersion phases of modified nano-Fe3O4 particles were studied by Fourier transform infrared (FTIR) spectrometry, X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The experimental results show that the nano-Fe3O4 particles modified by monooctadecyl maleate with the size of about 7-10 nm can be uniformly dispersed into styrene and fixed in the composite during the procedure of polymerization. Thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM) indicate that the thermal stability of polystyrene/nano-Fe3O4 composite is improved compared to that of pure polystyrene, and the composite is a sort of superparamagnetic materials.展开更多
Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene (CLPS) as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysila...Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene (CLPS) as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane (VTES), vinyl trimethoxysilane (VTMS) and γ-methacryloylpropyl trimethoxysilane (MPS). The treated glass fibers were analyzed by fourier transform infrared spectroscopy (FTIR). Dynamic mechanical thermal analysis (DMTA) and thermo-gravimetric analysis (TGA) were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy (SEM). The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.展开更多
The development of alternative wood composites based on the use of waste or recycled materials can be beneficial due to over exploitation of natural resources.Under this frame,an option for the successful utilization ...The development of alternative wood composites based on the use of waste or recycled materials can be beneficial due to over exploitation of natural resources.Under this frame,an option for the successful utilization of waste polystyrene which avoids environmental problems that formaldehyde adhesives cause and also reduces waste dis-posal,is its potential application as a binder for the production of value-added environmentally friendly and low cost wood composites.Two types of panel were successfully made,consisting of wood dust and two recycled poly-styrene contents,namely,15%and 30%.Both physical properties,water absorption and thickness swelling,and mechanical properties,modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength,were significantly improved as the recycled polystyrene content increased from 15%to 30%.Water absorption and thickness swelling after 24 h immersion in water were improved by 165%and 750%as the recycled polystyrene content increased from 15%to 30%.The magnitude of the improvement in mechanical properties however,was less pronounced than of the physical properties since modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength were increased by 43.6%,50%and 61.5%,respec-tively.The low viscosity of the recycled polystyrene caused more mobility inside the panel matrix and therefore,an improved penetration took place into adequate depth of the compressed dust particles.It is concluded that boards can be successfully produced using these waste raw materials,wood dust and recycled polystyrene in organic solvent as a binder,and therefore it can reduce waste disposal and provide cleaner production for the development of wood-based boards.展开更多
This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dio...This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with HPLC-ESI-MS. The influence of several operational parameters, including the eluant and its volume, the flow rate and acidity of water sample were investigated and optimized. Under the optimum conditions, the limits of detection were 1.0 ng/L, 2.5 and 4.5 ng/L for TCC, TCS, and MTCS, respectively. The linearity of the method was observed in the range of 5-2000 ng/L, with correlation coefficients (r2) >.99. The spiked recoveries of TCC, TCS and MTCS in water sampleswereachieved in the range of 89.5% -96.8% with RSD below 5.7%. The proposed method has been successfully applied to analyze real water samples and satisfactory results were achieved.展开更多
To tailor properties of polymer composites are very important for their applications.Very small concentrations of nanoparticles can significantly alter their physical characteristics.In this work,molecular dynamics si...To tailor properties of polymer composites are very important for their applications.Very small concentrations of nanoparticles can significantly alter their physical characteristics.In this work,molecular dynamics simulations are performed to study the thermodynamic and structural properties of polystyrene/C60(PS/C60)composites.The calculated densities,glass transition temperatures,and coefficient of thermal expansion of the bulk PS are in agreement with the experimental data available,implying that our calculations are reasonable.We find that the glass transition temperature Tg increases accordingly with an added concentration of C60 for PS/C60 composites.However,the self-diffusion coefficient D decreases with increase of addition of C60.For the volumetric coefficients of thermal expansion(CTE)of bulk PS and PS/C60 composites,it can be seen that the CTE increases with increasing content of C60 above Tg(rubbery region).However,the CTE decreases with increasing content of C60 below Tg(glassy region).展开更多
Polysiloxane-polystyrene composite latexes were prepared by two-stage emulsionpolymerization. Polymerization of styrene in swollen polysiloxane latex particles were studied.Formation of simple polystyrene particle in ...Polysiloxane-polystyrene composite latexes were prepared by two-stage emulsionpolymerization. Polymerization of styrene in swollen polysiloxane latex particles were studied.Formation of simple polystyrene particle in the 2nd-stage polymerization depends on the particlesize of the lst-stage latex and the polymerization temperature. Polystyrene domains in thevulcanizates reinforce the silicone rubbers effectively.展开更多
Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and en...Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and energy-dispersive spectroscopic results demonstrated that the polyanion of PSS^- is co-deposited into the PPy matrix and couldn't bestripped fiom the film extensively by dedoping.The doping level together with dipolaron content of the PPy-PSSAcomposite film increases during electrochemical polymerization process.SEM images revealed that the composite film hassmooth and compact morphology and AFM pictures suggested that PPy chains are possibly grown perpendicular to theelectrode surface.TGA tests indicated that the composite films has much better thermal stability than that of pure PPy.Furthermore,electrochemical studies showed that the relaxation process at certain holding potential has great effect on theshape of the cyclic voltammetric curves of PPy-PSSA composite film.The composite film exhibits cation and anionexchange during the redox process after undergoing the relaxation step.It is more difficult for divalent anion to enter thepolymer matrix than a univalent ion,and a large cation such as(CH_3CH_2CH_2CH_2)_4N^+ cannot be involved in the ionexchange process.展开更多
<div style="text-align:justify;"> <span style="font-family:Verdana;">The use of vegetable fibers composites in structures sometimes presents significant fires risks because of their hig...<div style="text-align:justify;"> <span style="font-family:Verdana;">The use of vegetable fibers composites in structures sometimes presents significant fires risks because of their high flammability. This work aims to study the impact of the addition of mineral filler (clay) on the fire behaviour of wood-polystyrene composites and their mechanical properties. Thus, composites containing 25% of expanded polystyrene binder have been produced. On this base material, proportions of clay ranging from 0% to 15% were gradually added. These samples were elaborated by compaction and for some them, submitted to thermoforming after drying. Both kinds of sample were subjected to flame persistence test;flexural strength and compressive strength test were also measured. The results show that composites without mineral filler ignite continuously until the total consumption and when the mineral filler content increases the combustion time decreases. The addition of the mineral filler allows these composites to pass from class M3 of moderately flammable combustible materials to class M2 of hardly flammable materials, according to the M classification of construction and furnishing materials. The measurement of the mechanical properties shows that the strengths increase when the filler content goes from 0% to 10% and then decrease. This leads to set the optimum content of mineral filler around 10%.</span> </div>展开更多
Environmental pollution is a whole world concern. One of the causes of </span><span><span style="font-family:Verdana;">that </span><span style="font-family:Verdana;">p...Environmental pollution is a whole world concern. One of the causes of </span><span><span style="font-family:Verdana;">that </span><span style="font-family:Verdana;">pollution</span></span><span><span style="font-family:Verdana;"> is the proliferation of plastic waste. Among these </span><span style="font-family:Verdana;">wastes</span><span style="font-family:Verdana;"> there is expanded </span></span><span style="font-family:Verdana;">polystyrene (EPS), mainly from </span><span style="font-family:Verdana;">packaging</span><span style="font-family:Verdana;">. This study aims to valorize EPS waste by developing a composite material from EPS waste and wood waste. For this purpose, a resin made of EPS has been elaborated by dissolving EPS in acetone. That resin was used as a binder in volume proportions of 15%, 20%, 25% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 30% to stabilize the samples. Some of them were thermoformed. The method of elaboration was based on a device consisting of an extruder for mixing the constituents, and a manual press for shaping and compacting the samples. Analyses show that the drying time depends on the composition of the mixture. Increasing the resin content leads to reduce water absorption and porosity of the samples;it also contributes to homogenize the internal structure of the samples. However, for the same resin contents, the thermoformed samples are less porous;they have </span><span style="font-family:Verdana;">more</span><span style="font-family:Verdana;"> homogeneous internal structure</span><span style="font-family:Verdana;">;and</span><span style="font-family:Verdana;"> absorb less water than non-thermoformed samples.展开更多
In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does ...In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.展开更多
Fe (III) 2,9,16,23 tertracarboxy phthalocyanine (Fe (III) taPc) was synthesized, and bonded to polystyrene (PS) with covalence by Friedel Crafts reaction to form a new polymer (Fe (III) taPc PS) (polymer (II))....Fe (III) 2,9,16,23 tertracarboxy phthalocyanine (Fe (III) taPc) was synthesized, and bonded to polystyrene (PS) with covalence by Friedel Crafts reaction to form a new polymer (Fe (III) taPc PS) (polymer (II)). UV VIS and Infrared spectra indicated that Fe (III) taPc was successfully bonded to PS. A photoreceptor device of sandwich structure consisting of alternate layers of polymer (II) and fullerene (C 60 ) was prepared. The experiment results show that the photoconductivity of the photoreceptor is higher than that of the single layer film of polymer (II) or C 60 , because of the charge transfer effect between the layers.展开更多
A series of polymer- supported Pd -Fe2O3 composite catalysts were prepared and their hydrogenation property mas investigated. It was found that the above catalysts have good catalytic hydrogenation activity for carbon...A series of polymer- supported Pd -Fe2O3 composite catalysts were prepared and their hydrogenation property mas investigated. It was found that the above catalysts have good catalytic hydrogenation activity for carbon - carbon double bonds systems and reusability. Furthermore, XPS and IR spectra shouted that active component in the composite catalysts is atomic Pd(0). An addition of a small amount of Fe2O3 has a promotive action upon hydrogenation activity of the catalysts, which indicated that there are some strong interactions (electron transfer) between Pd(0) and Fe(Ⅲ) species. Based on these results, a possible catalytic hydrogenation mechanism was also suggested.展开更多
The axial bearing capacity of prefabricated composite walls composed of inner and outer concrete wythes,expandable polystyrene(EPS)boards and steel sleeve connectors is investigated.An experimental study on the axial ...The axial bearing capacity of prefabricated composite walls composed of inner and outer concrete wythes,expandable polystyrene(EPS)boards and steel sleeve connectors is investigated.An experimental study on the axial bearing capacity of four prefabricated composite walls after fire treatment is carried out.Two of the prefabricated composite walls are normal-temperature specimens,and the others are treated with fire.The damage modes and crack development are observed,and the axial bearing capacity,lateral deformation of the specimens,and the concrete and reinforcing bar strain are tested.The results show that the ultimate bearing capacity of specimens after a fire is less than that of normal-temperature specimens;when the insulation board thicknesses are 40 mm and 60 mm,the decrease amplitudes are 20.8%and 16.8%,respectively.The maximum lateral deformation of specimens after a fire is greater than that of normal-temperature specimens,and under the same level of load,the lateral deformation increases as the insulation board thickness increases.Moreover,the strain values of the concrete and reinforcing bars of specimens after a fire are greater than those of normal-temperature specimens,and the strain values increase as the thickness of insulation board increases.展开更多
The novel method for preparing the polymer composite particles has been developed. It was tried to prepare polymer composite particles composed of polystyrene and carbon black with the phase separation method followed...The novel method for preparing the polymer composite particles has been developed. It was tried to prepare polymer composite particles composed of polystyrene and carbon black with the phase separation method followed by suspension polymerization. In order to prepare the polymer composite particles with the more uniform diameter, the styrene monomer droplets containing carbon black were formed with phase separation emulsification in which ethyl alcohol and water were used as the good solvent and the poor solvent for styrene monomer, respectively. In the experiment, the surfactant species and their concentrations, the pouring velocity of water and the weight ratio of carbon black to styrene monomer were mainly changed. Water was poured at the given pouring velocity into ethyl alcohol in which styrene monomer and an initiator were dissolved and carbon black was dispersed beforehand. The spherical polymer composite particles containing carbon black were prepared with Tween 20 and Tween 80 of nonionic surfactants and the irregular polymer composite particles were prepared with PVA, SDS and Kotamine. The diameters of polymer composite particles increased with the pouring velocity of water and with the weight ratio of carbon black to styrene monomer.展开更多
文摘In the current context of environmental challenges, this study focuses on developing innovative and eco-friendly composites using rice husk and recycled expanded polystyrene. This dual-responsibility approach valorizes a by-product like rice husk, often considered waste, and reuses polystyrene, a plastic waste, thereby contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene into a solvent to create a binder, which is then mixed with rice husk and cold-compacted into composite materials. The study examines the impact of two particle sizes (fine and coarse) and different proportions of recycled polystyrene binder. The results show significant variations in the mechanical characteristics of the composites, with Modulus of Rupture (MOR) values varying from 2.41 to 3.47 MPa, Modulus of Elasticity (MOE) ranging from 223.41 to 1497.2 MPa, and Stiffness Coefficient (K) from 5.04 to 33.96 N/mm. These characteristics demonstrate that these composites are appropriate for various construction applications, including interior decoration, panel claddings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only highlights the recycling of agricultural and plastic waste but also provides a localized approach to addressing global climate change challenges through the adoption of sustainable building materials.
文摘Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufacturing method that involves dissolving the polystyrene in a solvent followed by cold pressing. Various particle sizes and two binder dosages were investigated to assess their influence on the physico-mechanical properties of the composites. The mechanical properties obtained range from 2.54 to 4.47 MPa for the Modulus of Rupture (MOR) and from 686 to 1400 MPa for the Modulus of Elasticity in Bending (MOE). The results indicate that these composites have potential for applications in the construction sector, particularly for wood structures and interior decoration. Moreover, surface treatments could enhance their durability and mechanical properties. This research contributes to the valorization of agricultural and plastic waste as eco-friendly and economical construction materials.
基金Supported by National Natural Science Foundation of China(Nos.20674023 and 20801022)
文摘Fluorescent polystyrene(PS)/porphyrin(TPPA) composite nanospheres were successfully fabricated by electrospinning. The SEM images clearly show that owing to adding TPPA in PS, the averaged diameter of the composite nanospheres became smaller, from 1500 to 580 nm. Fourier-transform infrared(FTIR) spectra determined the chemical composition of the resulting PS/TPPA composite nanospheres. The photoluminescent(PL) spectral analysis indicates that the peak position of the composite nanospheres in either solid state or water is identical to that of pure TPPA, at about 652 nm, and is still unchangeable when they are left for at least 20 d, indicating the stable photoluminescent property of the fluorescent composite nanospheres.
基金Funded by the Natural Science Foundation of Guangdong Province (No. 020891)
文摘Monooctadecyl maleate, as a polymerizable surfactant, was synthesized by the mono-esterification of maleic anhydride and octadecanol, and was utilized to surface-modify nano-Fe3O4 particles. A polymerizable magnetic fluid was obtained by directly dispersing modified nano-Fe3O4 particles into styrene monomer, and the polystyrene/nano-Fe3O4 composite was prepared through free radical polymerization of polymerizable magnetic fluid. The structure and dispersion status in different dispersion phases of modified nano-Fe3O4 particles were studied by Fourier transform infrared (FTIR) spectrometry, X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The experimental results show that the nano-Fe3O4 particles modified by monooctadecyl maleate with the size of about 7-10 nm can be uniformly dispersed into styrene and fixed in the composite during the procedure of polymerization. Thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM) indicate that the thermal stability of polystyrene/nano-Fe3O4 composite is improved compared to that of pure polystyrene, and the composite is a sort of superparamagnetic materials.
基金Supported by National Natural Science Foundation of China (No.50872101,A3 Foresight Program-50821140308)National Basic Research Program of China (No.2009CB939704)a joint project of National Nature Science Foundation of China and Russian Foundation for Basic Research(No.NSFC-RFBR 51011120252)
文摘Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene (CLPS) as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane (VTES), vinyl trimethoxysilane (VTMS) and γ-methacryloylpropyl trimethoxysilane (MPS). The treated glass fibers were analyzed by fourier transform infrared spectroscopy (FTIR). Dynamic mechanical thermal analysis (DMTA) and thermo-gravimetric analysis (TGA) were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy (SEM). The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.
基金This research is co-financed by Greece and the European Union(European Social Fund-ESF)through the Operational Programme‘Human Resources,Development,Education and Lifelong Learning 2014-2020’in the context of the project‘Innovative wood plastic composites made from recycled polystyrene and recycled wood chips’(MIS 5048422).
文摘The development of alternative wood composites based on the use of waste or recycled materials can be beneficial due to over exploitation of natural resources.Under this frame,an option for the successful utilization of waste polystyrene which avoids environmental problems that formaldehyde adhesives cause and also reduces waste dis-posal,is its potential application as a binder for the production of value-added environmentally friendly and low cost wood composites.Two types of panel were successfully made,consisting of wood dust and two recycled poly-styrene contents,namely,15%and 30%.Both physical properties,water absorption and thickness swelling,and mechanical properties,modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength,were significantly improved as the recycled polystyrene content increased from 15%to 30%.Water absorption and thickness swelling after 24 h immersion in water were improved by 165%and 750%as the recycled polystyrene content increased from 15%to 30%.The magnitude of the improvement in mechanical properties however,was less pronounced than of the physical properties since modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength were increased by 43.6%,50%and 61.5%,respec-tively.The low viscosity of the recycled polystyrene caused more mobility inside the panel matrix and therefore,an improved penetration took place into adequate depth of the compressed dust particles.It is concluded that boards can be successfully produced using these waste raw materials,wood dust and recycled polystyrene in organic solvent as a binder,and therefore it can reduce waste disposal and provide cleaner production for the development of wood-based boards.
文摘This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with HPLC-ESI-MS. The influence of several operational parameters, including the eluant and its volume, the flow rate and acidity of water sample were investigated and optimized. Under the optimum conditions, the limits of detection were 1.0 ng/L, 2.5 and 4.5 ng/L for TCC, TCS, and MTCS, respectively. The linearity of the method was observed in the range of 5-2000 ng/L, with correlation coefficients (r2) >.99. The spiked recoveries of TCC, TCS and MTCS in water sampleswereachieved in the range of 89.5% -96.8% with RSD below 5.7%. The proposed method has been successfully applied to analyze real water samples and satisfactory results were achieved.
基金Project supported by the National Natural Science Foundation of China(Grant No.11704329)the Scientific Research Fund of Sichuan Provincial Education Department of China(Grant No.15ZB293)+1 种基金the Pre-Research Project of Yibin University of China(Grant No.2019YY06)the Open Research Fund of Computational Physics Key Laboratory of Sichuan Province at Yibin University of China(Grant No.JSWL2014KF02).
文摘To tailor properties of polymer composites are very important for their applications.Very small concentrations of nanoparticles can significantly alter their physical characteristics.In this work,molecular dynamics simulations are performed to study the thermodynamic and structural properties of polystyrene/C60(PS/C60)composites.The calculated densities,glass transition temperatures,and coefficient of thermal expansion of the bulk PS are in agreement with the experimental data available,implying that our calculations are reasonable.We find that the glass transition temperature Tg increases accordingly with an added concentration of C60 for PS/C60 composites.However,the self-diffusion coefficient D decreases with increase of addition of C60.For the volumetric coefficients of thermal expansion(CTE)of bulk PS and PS/C60 composites,it can be seen that the CTE increases with increasing content of C60 above Tg(rubbery region).However,the CTE decreases with increasing content of C60 below Tg(glassy region).
文摘Polysiloxane-polystyrene composite latexes were prepared by two-stage emulsionpolymerization. Polymerization of styrene in swollen polysiloxane latex particles were studied.Formation of simple polystyrene particle in the 2nd-stage polymerization depends on the particlesize of the lst-stage latex and the polymerization temperature. Polystyrene domains in thevulcanizates reinforce the silicone rubbers effectively.
基金This work was supported by the National Natural Science Foundation of China(No.50225311,20374034,50133010).
文摘Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and energy-dispersive spectroscopic results demonstrated that the polyanion of PSS^- is co-deposited into the PPy matrix and couldn't bestripped fiom the film extensively by dedoping.The doping level together with dipolaron content of the PPy-PSSAcomposite film increases during electrochemical polymerization process.SEM images revealed that the composite film hassmooth and compact morphology and AFM pictures suggested that PPy chains are possibly grown perpendicular to theelectrode surface.TGA tests indicated that the composite films has much better thermal stability than that of pure PPy.Furthermore,electrochemical studies showed that the relaxation process at certain holding potential has great effect on theshape of the cyclic voltammetric curves of PPy-PSSA composite film.The composite film exhibits cation and anionexchange during the redox process after undergoing the relaxation step.It is more difficult for divalent anion to enter thepolymer matrix than a univalent ion,and a large cation such as(CH_3CH_2CH_2CH_2)_4N^+ cannot be involved in the ionexchange process.
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">The use of vegetable fibers composites in structures sometimes presents significant fires risks because of their high flammability. This work aims to study the impact of the addition of mineral filler (clay) on the fire behaviour of wood-polystyrene composites and their mechanical properties. Thus, composites containing 25% of expanded polystyrene binder have been produced. On this base material, proportions of clay ranging from 0% to 15% were gradually added. These samples were elaborated by compaction and for some them, submitted to thermoforming after drying. Both kinds of sample were subjected to flame persistence test;flexural strength and compressive strength test were also measured. The results show that composites without mineral filler ignite continuously until the total consumption and when the mineral filler content increases the combustion time decreases. The addition of the mineral filler allows these composites to pass from class M3 of moderately flammable combustible materials to class M2 of hardly flammable materials, according to the M classification of construction and furnishing materials. The measurement of the mechanical properties shows that the strengths increase when the filler content goes from 0% to 10% and then decrease. This leads to set the optimum content of mineral filler around 10%.</span> </div>
文摘Environmental pollution is a whole world concern. One of the causes of </span><span><span style="font-family:Verdana;">that </span><span style="font-family:Verdana;">pollution</span></span><span><span style="font-family:Verdana;"> is the proliferation of plastic waste. Among these </span><span style="font-family:Verdana;">wastes</span><span style="font-family:Verdana;"> there is expanded </span></span><span style="font-family:Verdana;">polystyrene (EPS), mainly from </span><span style="font-family:Verdana;">packaging</span><span style="font-family:Verdana;">. This study aims to valorize EPS waste by developing a composite material from EPS waste and wood waste. For this purpose, a resin made of EPS has been elaborated by dissolving EPS in acetone. That resin was used as a binder in volume proportions of 15%, 20%, 25% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 30% to stabilize the samples. Some of them were thermoformed. The method of elaboration was based on a device consisting of an extruder for mixing the constituents, and a manual press for shaping and compacting the samples. Analyses show that the drying time depends on the composition of the mixture. Increasing the resin content leads to reduce water absorption and porosity of the samples;it also contributes to homogenize the internal structure of the samples. However, for the same resin contents, the thermoformed samples are less porous;they have </span><span style="font-family:Verdana;">more</span><span style="font-family:Verdana;"> homogeneous internal structure</span><span style="font-family:Verdana;">;and</span><span style="font-family:Verdana;"> absorb less water than non-thermoformed samples.
文摘Fluoroalkyl end-capped vinyltrimethoxysilane-<i><span style="font-family:Verdana;">N</span></i><span><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;">N</span></i></span><span style="font-family:Verdana;">-dimethylacrylamide cooli</span><span style="font-family:;" "=""><span style="font-family:Verdana;">gomer [R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(CH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">-CHSi(OMe)</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">x</span></sub></i><span style="font-family:Verdana;">-(CH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">-CHC(=O)NMe</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">y</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">;R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;"> = CF(CF</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">)OC</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">F</span><sub><span style="font-family:Verdana;">7</span></sub><span style="font-family:Verdana;">:</span></span><span style="font-family:;" "=""><span style="font-family:Verdana;"> R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM)</span><i><sub><span style="font-family:Verdana;">x</span></sub></i><span style="font-family:Verdana;">-(DMAA)</span><i><sub><span style="font-family:Verdana;">y</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">] was synthesized by reaction of fluoroalkanoyl peroxide [R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-C(=O)O-O(O=)C-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">] with vinyltrimethoxysilane (VM) and </span><i><span style="font-family:Verdana;">N</span></i><span><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;">N</span></i></span><span style="font-family:Verdana;">-</span></span><span style="font-family:Verdana;">dimethylacrylamide (DMAA). The modified glass surface treated with the</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> cooligomeric nanoparticles [R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">x</span></sub></i><span style="font-family:Verdana;">-(DMAA)</span><i><sub><span style="font-family:Verdana;">y</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">] prepared under the sol-gel reaction of the cooligomer under alkaline conditions was found to exhibit an oleophobic/superhydrophilic property, although the corresponding fluorinated homooligomeric nanoparticles [R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">n</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">] afforded an </span><span style="font-family:Verdana;">oleophobic/hydrophobic property on the modified surface under similar </span><span style="font-family:Verdana;">con</span><span><span style="font-family:Verdana;">ditions. R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">n</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">/R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">x</span></sub></i><span style="font-family:Verdana;">-(DMAA)</span><i><sub><span style="font-family:Verdana;">y</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">/</span><b><i><span style="font-family:Verdana;">PSt</span></i></b><span style="font-family:Verdana;"> (micro-sized</span></span> <span style="font-family:Verdana;">polystyrene particles) composites, which were prepared by the sol-gel reac</span><span style="font-family:Verdana;">tions of the corresponding homooligomer and cooligomer in the presence of </span><b><i><span style="font-family:Verdana;">PSt </span></i></b><span style="font-family:Verdana;">particle under alkaline conditions, provided an oleophobic/superhydrophilic </span><span style="font-family:Verdana;">property on the modified surface. However, it was demonstrated that the</span><span><span style="font-family:Verdana;"> surface wettability on the modified surface treated with the R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-</span></span><span><span style="font-family:Verdana;">SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">n</span></sub></i><span style="font-family:Verdana;">-</span></span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">/R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM-SiO</span><sub><span style="font-family:Verdana;">3/2</span></sub><span style="font-family:Verdana;">)</span><i><sub><span style="font-family:Verdana;">x</span></sub></i><span style="font-family:Verdana;">-(DMAA)</span><i><sub><span style="font-family:Verdana;">y</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">/</span><b><i><span style="font-family:Verdana;">PSt</span></i></b><span style="font-family:Verdana;"> composites changes dramatically from oleophobic/superhydrophilic to superoleophilic/superhydrophilic </span><span style="font-family:Verdana;">and superoleophilic/superhydrophobic characteristics, increasing with </span><span style="font-family:Verdana;">greater </span><span><span style="font-family:Verdana;">feed ratios (mg/mg) of the R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;">-(VM)</span><i><sub><span style="font-family:Verdana;">n</span></sub></i><span style="font-family:Verdana;">-R</span><sub><span style="font-family:Verdana;">F</span></sub><span style="font-family:Verdana;"> homooligomer in homooligo</span></span><span style="font-family:Verdana;">mer/cooligo</span></span><span style="font-family:Verdana;">mer from 0 to 100 in the preparation of the composites. Such controlled surfac</span>
文摘In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.
文摘Fe (III) 2,9,16,23 tertracarboxy phthalocyanine (Fe (III) taPc) was synthesized, and bonded to polystyrene (PS) with covalence by Friedel Crafts reaction to form a new polymer (Fe (III) taPc PS) (polymer (II)). UV VIS and Infrared spectra indicated that Fe (III) taPc was successfully bonded to PS. A photoreceptor device of sandwich structure consisting of alternate layers of polymer (II) and fullerene (C 60 ) was prepared. The experiment results show that the photoconductivity of the photoreceptor is higher than that of the single layer film of polymer (II) or C 60 , because of the charge transfer effect between the layers.
文摘A series of polymer- supported Pd -Fe2O3 composite catalysts were prepared and their hydrogenation property mas investigated. It was found that the above catalysts have good catalytic hydrogenation activity for carbon - carbon double bonds systems and reusability. Furthermore, XPS and IR spectra shouted that active component in the composite catalysts is atomic Pd(0). An addition of a small amount of Fe2O3 has a promotive action upon hydrogenation activity of the catalysts, which indicated that there are some strong interactions (electron transfer) between Pd(0) and Fe(Ⅲ) species. Based on these results, a possible catalytic hydrogenation mechanism was also suggested.
基金The National Key Research and Development Program of China(No.2016YFC0701703)the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(No.2016TM045J)the Scientific Innovation Research of Graduate Students in Jiangsu Province(No.KYLX_0151)
文摘The axial bearing capacity of prefabricated composite walls composed of inner and outer concrete wythes,expandable polystyrene(EPS)boards and steel sleeve connectors is investigated.An experimental study on the axial bearing capacity of four prefabricated composite walls after fire treatment is carried out.Two of the prefabricated composite walls are normal-temperature specimens,and the others are treated with fire.The damage modes and crack development are observed,and the axial bearing capacity,lateral deformation of the specimens,and the concrete and reinforcing bar strain are tested.The results show that the ultimate bearing capacity of specimens after a fire is less than that of normal-temperature specimens;when the insulation board thicknesses are 40 mm and 60 mm,the decrease amplitudes are 20.8%and 16.8%,respectively.The maximum lateral deformation of specimens after a fire is greater than that of normal-temperature specimens,and under the same level of load,the lateral deformation increases as the insulation board thickness increases.Moreover,the strain values of the concrete and reinforcing bars of specimens after a fire are greater than those of normal-temperature specimens,and the strain values increase as the thickness of insulation board increases.
文摘The novel method for preparing the polymer composite particles has been developed. It was tried to prepare polymer composite particles composed of polystyrene and carbon black with the phase separation method followed by suspension polymerization. In order to prepare the polymer composite particles with the more uniform diameter, the styrene monomer droplets containing carbon black were formed with phase separation emulsification in which ethyl alcohol and water were used as the good solvent and the poor solvent for styrene monomer, respectively. In the experiment, the surfactant species and their concentrations, the pouring velocity of water and the weight ratio of carbon black to styrene monomer were mainly changed. Water was poured at the given pouring velocity into ethyl alcohol in which styrene monomer and an initiator were dissolved and carbon black was dispersed beforehand. The spherical polymer composite particles containing carbon black were prepared with Tween 20 and Tween 80 of nonionic surfactants and the irregular polymer composite particles were prepared with PVA, SDS and Kotamine. The diameters of polymer composite particles increased with the pouring velocity of water and with the weight ratio of carbon black to styrene monomer.