Composites formed by adding nano-scale particles to a polymer matrix results in improving electrical, mechanical, and thermal properties of the composite. Good tribological properties can be obtained for polymers fill...Composites formed by adding nano-scale particles to a polymer matrix results in improving electrical, mechanical, and thermal properties of the composite. Good tribological properties can be obtained for polymers filled with nano-scale fillers compared to that filled with micro-scale particles. The friction and wear resistance of these composites is found to increase with increasing filler concentration. It is also possible to use multi-functional fillers to develop high performance composites which cannot be achieved by using a single filler.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
Rheological and thermal properties of LD-PE and LD-PE + 65 vol% Ni composite were examined by viscosity, pvt and thermal conductivity measurements at a wide range of shear rate, temperature and pressure. The typical s...Rheological and thermal properties of LD-PE and LD-PE + 65 vol% Ni composite were examined by viscosity, pvt and thermal conductivity measurements at a wide range of shear rate, temperature and pressure. The typical shear-thinning viscosity of LD-PE polymer melt was enhanced up to four times by adding 65 vol% Ni braze metal particles. LD-PE show increasing specific volume versus temperature, decreasing with pressure and braze particle filler content. Variation of specific volume of LD-PE was reduced to 5% by admixing 65 vol% rigid Ni braze metal particles. Thermal conductivity of LD-PE was increased up to 15 times in the composite, reduced by decreasing pressure at temperature exceeding 80℃. Furthermore, thermal analysis was performed in modulated DSC to determine the specific heat capacity in wide temperature range. Viscosity and pvt-data were fitted using Cross-WLF equation and 2-domain Tait-pvt model, respectively. Simulation of LD-PE and LD-PE + 65 vol% Ni composite was performed based on rheological and thermal properties to define processing parameters. Simulation and injection molding of ring-shaped LD-PE + 65 vol% Ni composite braze metal preforms were performed successfully.展开更多
The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount o...The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount of nanosized particles are added to a polymer matrix. The addition of inorganic solid nanoparticles (typically in the form of fibres, flakes, spheres or fine particles) into polymer matrix increases their physical, structural and mechanical properties. Since the polymer-nano composites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. This leads to focus on preparation & characterization of polymer nanocomposite. This article is intended to review the status of worldwide research in this aspect. The successful application of nano particles depends upon both the correct preparation techniques followed by testing through characterization. Surface modification can improve the inherent characteristics of the nano particles and serve to prepare nano composites inexistent in nature. Therefore, some tools as their various properties like electrical, optical and morphological can be used to optimize the preparation of polymer nano composites. This chapter will make an overview about different routes to prepare polymer-based nano composites by extrusion, synthesis of nano particles by sol-gel reactions, sputtering and mainly by physical evaporation deposition method.展开更多
Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of sol...Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of solid-state electrolyte is vital to commercialize SSLBs.Composite polymer electrolyte(CPE),derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties.The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE,improving its ionic conductivity,mechanical properties,thermal and electrochemical stability,as well as interface compatibility with both electrodes.In this review,the effects of particle characteristics including its species,size,proportion,morphology on the ionic conductivity and mechanical properties of CPE are reviewed.Meanwhile,some novel composite strategies are also introduced including surface modification,hybridization,and alignment of particles in polymer matrices,as well as some new preparation methods of CPE.The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism.Finally,a perspective on the direction of future CPE development for SSLBs is presented.展开更多
Polymer-nanoinorganic particles composite membranes present an interesting approach for improving the physical and chemical,as well as separation properties of polymer membranes,because they possess character-istics o...Polymer-nanoinorganic particles composite membranes present an interesting approach for improving the physical and chemical,as well as separation properties of polymer membranes,because they possess character-istics of both organic and inorganic membranes such as good permeability,selectivity,mechanical strength,ther-mal stability and so on.The preparations and structures of polymer-nanoinorganic particles composite membranes and their unique properties are reviewed.展开更多
High Density Polyethylene (HDPE) composites reinforced with treated bio-filler from Argan-Nut Shell (ANS) at various filler contents are prepared by extrusion and injection molding processes. The microstructures o...High Density Polyethylene (HDPE) composites reinforced with treated bio-filler from Argan-Nut Shell (ANS) at various filler contents are prepared by extrusion and injection molding processes. The microstructures of the composites are charac- terized by Fourier Transform Infrared Spectroscopy (FTIS) and Scanning Electron Microscopy (SEM); the thermal stability is analyzed by Thermogravimetric Analysis (TGA), and their mechanical properties are investigated by dynamical mechanical analysis and rheological testing. The morphological and structural results indicate an improvement in adhesion between the ANS fillers and HDPE matrix upon alkali treatment. The mechanical properties of the composites show a significant increase in young's modulus with the addition of filler, a gain of 58% is marked compared to neat polymer, Thermal analysis reveals that the incorporation of bio-filler in polymer results in a decrease in decomposition temperatures. This research offers an ecological alternative to upgrade the valorization of abundant and unexploited Moroccan resources. In addition, the possibility of finding uses for ANS in composite manufacturing will help open new markets for what is normally considered waste or for use in low value products.展开更多
文摘Composites formed by adding nano-scale particles to a polymer matrix results in improving electrical, mechanical, and thermal properties of the composite. Good tribological properties can be obtained for polymers filled with nano-scale fillers compared to that filled with micro-scale particles. The friction and wear resistance of these composites is found to increase with increasing filler concentration. It is also possible to use multi-functional fillers to develop high performance composites which cannot be achieved by using a single filler.
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.
文摘Rheological and thermal properties of LD-PE and LD-PE + 65 vol% Ni composite were examined by viscosity, pvt and thermal conductivity measurements at a wide range of shear rate, temperature and pressure. The typical shear-thinning viscosity of LD-PE polymer melt was enhanced up to four times by adding 65 vol% Ni braze metal particles. LD-PE show increasing specific volume versus temperature, decreasing with pressure and braze particle filler content. Variation of specific volume of LD-PE was reduced to 5% by admixing 65 vol% rigid Ni braze metal particles. Thermal conductivity of LD-PE was increased up to 15 times in the composite, reduced by decreasing pressure at temperature exceeding 80℃. Furthermore, thermal analysis was performed in modulated DSC to determine the specific heat capacity in wide temperature range. Viscosity and pvt-data were fitted using Cross-WLF equation and 2-domain Tait-pvt model, respectively. Simulation of LD-PE and LD-PE + 65 vol% Ni composite was performed based on rheological and thermal properties to define processing parameters. Simulation and injection molding of ring-shaped LD-PE + 65 vol% Ni composite braze metal preforms were performed successfully.
文摘The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount of nanosized particles are added to a polymer matrix. The addition of inorganic solid nanoparticles (typically in the form of fibres, flakes, spheres or fine particles) into polymer matrix increases their physical, structural and mechanical properties. Since the polymer-nano composites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. This leads to focus on preparation & characterization of polymer nanocomposite. This article is intended to review the status of worldwide research in this aspect. The successful application of nano particles depends upon both the correct preparation techniques followed by testing through characterization. Surface modification can improve the inherent characteristics of the nano particles and serve to prepare nano composites inexistent in nature. Therefore, some tools as their various properties like electrical, optical and morphological can be used to optimize the preparation of polymer nano composites. This chapter will make an overview about different routes to prepare polymer-based nano composites by extrusion, synthesis of nano particles by sol-gel reactions, sputtering and mainly by physical evaporation deposition method.
基金This work was financially supported by the National Key R&D Program of China(Grant No.2018YFB0104300)the Beijing Municipal Natural Science Foundation(Grant No.2202027)the China Scholarship Council(No.202006460047).
文摘Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of solid-state electrolyte is vital to commercialize SSLBs.Composite polymer electrolyte(CPE),derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties.The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE,improving its ionic conductivity,mechanical properties,thermal and electrochemical stability,as well as interface compatibility with both electrodes.In this review,the effects of particle characteristics including its species,size,proportion,morphology on the ionic conductivity and mechanical properties of CPE are reviewed.Meanwhile,some novel composite strategies are also introduced including surface modification,hybridization,and alignment of particles in polymer matrices,as well as some new preparation methods of CPE.The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism.Finally,a perspective on the direction of future CPE development for SSLBs is presented.
基金The authors acknowledge the National Key Funda-mental Research Development Plan(No.2003CB615705)for giving financial supports in this project.
文摘Polymer-nanoinorganic particles composite membranes present an interesting approach for improving the physical and chemical,as well as separation properties of polymer membranes,because they possess character-istics of both organic and inorganic membranes such as good permeability,selectivity,mechanical strength,ther-mal stability and so on.The preparations and structures of polymer-nanoinorganic particles composite membranes and their unique properties are reviewed.
文摘High Density Polyethylene (HDPE) composites reinforced with treated bio-filler from Argan-Nut Shell (ANS) at various filler contents are prepared by extrusion and injection molding processes. The microstructures of the composites are charac- terized by Fourier Transform Infrared Spectroscopy (FTIS) and Scanning Electron Microscopy (SEM); the thermal stability is analyzed by Thermogravimetric Analysis (TGA), and their mechanical properties are investigated by dynamical mechanical analysis and rheological testing. The morphological and structural results indicate an improvement in adhesion between the ANS fillers and HDPE matrix upon alkali treatment. The mechanical properties of the composites show a significant increase in young's modulus with the addition of filler, a gain of 58% is marked compared to neat polymer, Thermal analysis reveals that the incorporation of bio-filler in polymer results in a decrease in decomposition temperatures. This research offers an ecological alternative to upgrade the valorization of abundant and unexploited Moroccan resources. In addition, the possibility of finding uses for ANS in composite manufacturing will help open new markets for what is normally considered waste or for use in low value products.