GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that rel...GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that relative densities decrease with increasing GF fraction, and the 50μm-GF reinforced specimens exhibit a better densification than the 300μm-GF reinforced ones. The GF particles distribute quite uniformly inPb matrix, and the composites fabricated at low sintering temperature （〈200℃） possess fine-grain microstructure. The addition of GF significantly improves the strength of the Pb composites, and the ultimate tensile strength of the Pb composite reinforcedwith the addition of 50μm-0.5% GF（mass fraction）is about 30MPa higher than that of GF-free sample. For all composites groups, increasing the reinforcement content from 0.5%to 2%（mass fraction）results in a decrease in both tensile strength and ductility.展开更多
The polyvinyl chloride (PVC) composites containing fly ash of various grit sizes and contents were prepared by hot pressing. The hardness, impact strength of the composites were measured, and their friction and wear p...The polyvinyl chloride (PVC) composites containing fly ash of various grit sizes and contents were prepared by hot pressing. The hardness, impact strength of the composites were measured, and their friction and wear properties under dry and water lubrication sliding against quenched AISI-1045 steel were evaluated on an MM-200 tester. The fractograph of impact specimens, worn surfaces of the composites and their transfer films on the counterpart steel surfaces were observed with a scanning electron microscope and an optical microscope. Experimental results show that the composites containing 50% 74147μm fly ash have the highest hardness, highest impact strength and smallest wear rate. The wear rate of the composite is reduced by over two orders of magnitude. However, the composite containing over 50% fly ash has decreased wear-resistance, which is attributed to the weakened interaction between the filler and the polymer matrix in the presence of inadequate polymer matrix. The improved wear-resistance of the composite under dry sliding against the steel is attributed to the formation of the composite transfer film thereon.展开更多
High aspect ratio Phlogopite mica was used to enhance the dimensional stability and mechanical properties of extruded rigid Polyvinyl Chloride (PVC) foam. Mica was added to rigid PVC compound at different concentratio...High aspect ratio Phlogopite mica was used to enhance the dimensional stability and mechanical properties of extruded rigid Polyvinyl Chloride (PVC) foam. Mica was added to rigid PVC compound at different concentrations (0 - 20 wt%) and processed using a single screw profile extruder. PVC foam-Mica composites were characterized for their dimensional stability, and structural, thermal, and mechanical properties. Experimental results showed that the dimensional stability increased by 44% and heat resistance of the samples improved as the amount of mica increased in the composites. The storage modulus and tensile strength of the composites were also enhanced with the addition of mica. However, increasing the concentration of mica had no significant effect on the impact and flexural properties of the composites. SEM micrographs show good dispersion and orientation of the mica flakes along the cell walls of the PVC foam. Overall, the platy structure and physical properties of mica seemed to have played an important role in providing good interfacial bonding with the cell membranes of the foam, thus enhancing the dimensional stability of the PVC- Mica foam composites.展开更多
A new three-phase PZT C/PVC composite comprising PZT（50 vol%）,nanocrystalline PVC （50 vol%） and a small volume fraction f of black（C0was prepared by the hot-pressing technique.The dielectric property of the comp...A new three-phase PZT C/PVC composite comprising PZT（50 vol%）,nanocrystalline PVC （50 vol%） and a small volume fraction f of black（C0was prepared by the hot-pressing technique.The dielectric property of the composite as α function of the frequency and the dielectric and piezoelectric properties as α function of the volume fraction f of C were studied.The measured dielectric property demonstrates that α percolation transition occurs in the three-phase composites as in normal two-phase metal-insulator continuum media.The dielectric constant varies slightly with f at f〈0.1 and increases rapidly when f is close to the percolation threshold at 1kHz.The optimum properties were obtained for f=0.5 before the percolation threshold in the PZT/C/PVC（50/f/（50-f）vol%）composite with its d33（20pC/N） being 50% higher than that of the PZT/PVC（50/50vol%）,and its g33（47.23×10^-3Vm/N）and Kp（0.25） much higher than the earlier reported values,XRD patterns and P-E hysteresis loops were used to interpret the experimental results.展开更多
Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fa...Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fabricated using different compounds of PVC. Mica is useful particulate filler extensively used to enhance the performance of many polymeric materials. It surface resistance and arc resistance improving its mechanical properties. In the present research work mica filled PVC composites of different concentrations were prepared using untreated and surface treated water ground mica of different particle size. Mica filled PVC composites were compounded for various compositions and test samples were prepared using compression moulding process. These samples were tested for electrical insulation and mechanical properties. The results shows enhancement in dielectric properties with improvement in Young’s modulus, stiffness, reduction in elongation at break and slight increase in shore D hardness of composites. Scanning electron microscopy was used to test the morphology of the samples which has shown proper distributions and adhesion of the filler mica in PVC matrix. There was some effect of surface treatment of mica on its mechanical and dielectric properties of the composite.展开更多
The inclusion of CaCO3 and kaolin in polyvinyl chloride (PVC) polymer matrices greatly enhances the physical and mechanical properties of the composite. In this study, the effects of kaolin and surface treatment of Ca...The inclusion of CaCO3 and kaolin in polyvinyl chloride (PVC) polymer matrices greatly enhances the physical and mechanical properties of the composite. In this study, the effects of kaolin and surface treatment of CaCO3 and kaolin particles on the microstructure and mechanical properties of PVC composites filled with kaolin particles via melt blending method were studied by means of SEM, tensile, Charpy impact testing, and FTIR. Treated and untreated kao-lin particles were dispersed in matrices of PVC resin at different concentrations up to 30 wt percentage. The tensile strength, elastic modulus, strain to failure and morphology of the resulting composites were measured for various filler loadings. Uniform dispersion of the fillers into the matrix proved to be a critical factor. SEM images revealed that small sized particles were more agglomerated than micron-sized particles and the amount of agglomerates increased with increasing particle content. Silane treated Kaolin-CaCO3/PVC composites had superior tensile and impact strengths to untreated kaolin-CaCO3/PVC composites. The Young’s modulus of all composites increased with increasing particle content up to maximum at 10% filler loading followed by gradually decreasing as content increased.展开更多
The present work describes the viability of a mortar binder based on two industrial by-products: poly(vinyl chloride) (PVC) particles from scrap and anhydrite (CaSO4) from fluorgypsum. Mortar composites were made inco...The present work describes the viability of a mortar binder based on two industrial by-products: poly(vinyl chloride) (PVC) particles from scrap and anhydrite (CaSO4) from fluorgypsum. Mortar composites were made incorporating different amounts of PVC particles and cured at constant room temperature during various periods of time. From X-ray diffraction, it was possible to follow the hydration process and to estimate the effect of the PVC particles on anhydrite transformation to gypsum (CaSO4·2H2O). Compressive strength from uniaxial testing was measured from stress-strain curves carried out at room temperature. According to these results, the hydration rates of the composites depend on the concentration of PVC particles and there is an enhancement in their compressive strength as particle content increases, reaching values of 36 MPa after 28 days.展开更多
文摘GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that relative densities decrease with increasing GF fraction, and the 50μm-GF reinforced specimens exhibit a better densification than the 300μm-GF reinforced ones. The GF particles distribute quite uniformly inPb matrix, and the composites fabricated at low sintering temperature （〈200℃） possess fine-grain microstructure. The addition of GF significantly improves the strength of the Pb composites, and the ultimate tensile strength of the Pb composite reinforcedwith the addition of 50μm-0.5% GF（mass fraction）is about 30MPa higher than that of GF-free sample. For all composites groups, increasing the reinforcement content from 0.5%to 2%（mass fraction）results in a decrease in both tensile strength and ductility.
文摘The polyvinyl chloride (PVC) composites containing fly ash of various grit sizes and contents were prepared by hot pressing. The hardness, impact strength of the composites were measured, and their friction and wear properties under dry and water lubrication sliding against quenched AISI-1045 steel were evaluated on an MM-200 tester. The fractograph of impact specimens, worn surfaces of the composites and their transfer films on the counterpart steel surfaces were observed with a scanning electron microscope and an optical microscope. Experimental results show that the composites containing 50% 74147μm fly ash have the highest hardness, highest impact strength and smallest wear rate. The wear rate of the composite is reduced by over two orders of magnitude. However, the composite containing over 50% fly ash has decreased wear-resistance, which is attributed to the weakened interaction between the filler and the polymer matrix in the presence of inadequate polymer matrix. The improved wear-resistance of the composite under dry sliding against the steel is attributed to the formation of the composite transfer film thereon.
文摘High aspect ratio Phlogopite mica was used to enhance the dimensional stability and mechanical properties of extruded rigid Polyvinyl Chloride (PVC) foam. Mica was added to rigid PVC compound at different concentrations (0 - 20 wt%) and processed using a single screw profile extruder. PVC foam-Mica composites were characterized for their dimensional stability, and structural, thermal, and mechanical properties. Experimental results showed that the dimensional stability increased by 44% and heat resistance of the samples improved as the amount of mica increased in the composites. The storage modulus and tensile strength of the composites were also enhanced with the addition of mica. However, increasing the concentration of mica had no significant effect on the impact and flexural properties of the composites. SEM micrographs show good dispersion and orientation of the mica flakes along the cell walls of the PVC foam. Overall, the platy structure and physical properties of mica seemed to have played an important role in providing good interfacial bonding with the cell membranes of the foam, thus enhancing the dimensional stability of the PVC- Mica foam composites.
文摘A new three-phase PZT C/PVC composite comprising PZT（50 vol%）,nanocrystalline PVC （50 vol%） and a small volume fraction f of black（C0was prepared by the hot-pressing technique.The dielectric property of the composite as α function of the frequency and the dielectric and piezoelectric properties as α function of the volume fraction f of C were studied.The measured dielectric property demonstrates that α percolation transition occurs in the three-phase composites as in normal two-phase metal-insulator continuum media.The dielectric constant varies slightly with f at f〈0.1 and increases rapidly when f is close to the percolation threshold at 1kHz.The optimum properties were obtained for f=0.5 before the percolation threshold in the PZT/C/PVC（50/f/（50-f）vol%）composite with its d33（20pC/N） being 50% higher than that of the PZT/PVC（50/50vol%）,and its g33（47.23×10^-3Vm/N）and Kp（0.25） much higher than the earlier reported values,XRD patterns and P-E hysteresis loops were used to interpret the experimental results.
文摘Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fabricated using different compounds of PVC. Mica is useful particulate filler extensively used to enhance the performance of many polymeric materials. It surface resistance and arc resistance improving its mechanical properties. In the present research work mica filled PVC composites of different concentrations were prepared using untreated and surface treated water ground mica of different particle size. Mica filled PVC composites were compounded for various compositions and test samples were prepared using compression moulding process. These samples were tested for electrical insulation and mechanical properties. The results shows enhancement in dielectric properties with improvement in Young’s modulus, stiffness, reduction in elongation at break and slight increase in shore D hardness of composites. Scanning electron microscopy was used to test the morphology of the samples which has shown proper distributions and adhesion of the filler mica in PVC matrix. There was some effect of surface treatment of mica on its mechanical and dielectric properties of the composite.
文摘The inclusion of CaCO3 and kaolin in polyvinyl chloride (PVC) polymer matrices greatly enhances the physical and mechanical properties of the composite. In this study, the effects of kaolin and surface treatment of CaCO3 and kaolin particles on the microstructure and mechanical properties of PVC composites filled with kaolin particles via melt blending method were studied by means of SEM, tensile, Charpy impact testing, and FTIR. Treated and untreated kao-lin particles were dispersed in matrices of PVC resin at different concentrations up to 30 wt percentage. The tensile strength, elastic modulus, strain to failure and morphology of the resulting composites were measured for various filler loadings. Uniform dispersion of the fillers into the matrix proved to be a critical factor. SEM images revealed that small sized particles were more agglomerated than micron-sized particles and the amount of agglomerates increased with increasing particle content. Silane treated Kaolin-CaCO3/PVC composites had superior tensile and impact strengths to untreated kaolin-CaCO3/PVC composites. The Young’s modulus of all composites increased with increasing particle content up to maximum at 10% filler loading followed by gradually decreasing as content increased.
文摘The present work describes the viability of a mortar binder based on two industrial by-products: poly(vinyl chloride) (PVC) particles from scrap and anhydrite (CaSO4) from fluorgypsum. Mortar composites were made incorporating different amounts of PVC particles and cured at constant room temperature during various periods of time. From X-ray diffraction, it was possible to follow the hydration process and to estimate the effect of the PVC particles on anhydrite transformation to gypsum (CaSO4·2H2O). Compressive strength from uniaxial testing was measured from stress-strain curves carried out at room temperature. According to these results, the hydration rates of the composites depend on the concentration of PVC particles and there is an enhancement in their compressive strength as particle content increases, reaching values of 36 MPa after 28 days.
