The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and ...The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and the optimization of raw materials inspection,steel pipe surface pretreatments,and water cooling control on a coating application process.The coating properties meet ISO standard 21809 on buried or submerged 3PP pipelines used in the petroleum and natural gas industries.Differential scanning calorimetry and X-ray diffraction were used to analyze the crystallinities and grain sizes of polypropylene(PP)top coats with different cooling rates.Increasing the melt cooling rate reduces the crystallinity and grain size of the PP top coat and enhances its strength and toughness.展开更多
By applying the reinforcing and toughening effect of calcium carbonate （CaCO3） nanoparticles on polypropylene, foam sheets of good performance were successfully fabricated by extrusion. The equipment and conditions ...By applying the reinforcing and toughening effect of calcium carbonate （CaCO3） nanoparticles on polypropylene, foam sheets of good performance were successfully fabricated by extrusion. The equipment and conditions of the extrusion were explored. The mechanical properties of the produced foam sheets were tested. The effect of CaCO3 nano-particles on the mechanical properties and the cellular structure of the sheets was comprehensively studied. The experimental results show that the optimum content of CaCO3 nano-particles in the composite material was -4wt%. At this content, the nano-particles were well dispersed in the substrate, and the composite material had maximum tensile strength and impact strength. Surface treatment of the nano-particles only affected the impact strength of the composite material. CaCO3 micro-particles, on the other hand, showed little effect on the properties of the composite material when the micro-particles content was less than 5 wt%. At a content higher than 5wt%, the properties of the composite material significantly worsened.展开更多
In order to improve the dimensional stability of wood-polymer composites, wood flour pre-treated by polyethylene glycol （PEG） at two different concentrations and then thermally treated at 140℃, was used as raw mate...In order to improve the dimensional stability of wood-polymer composites, wood flour pre-treated by polyethylene glycol （PEG） at two different concentrations and then thermally treated at 140℃, was used as raw material to produce wood flour/poly- propylene （PP） composites at a wood content of 40%. The structure of modified wood flour was analyzed with a scanning electron microscope （SEM） and its effect on the physical and mechanical properties of wood flour/PP composites was evaluated. The SEM results indicated the ＂bulking＂ effect of PEG on wood flour, which resulted in reduced water uptake. The combination of PEG and heat treatment further improved the moisture resistance of the composites. However, PEG modification had a negative effect on the flexural modulus of rupture （MOR） and the modulus of elasticity （MOE）; whereas heat treatment partly compensated for this reduc- tion. For dynamic mechanical properties, PEG treatment decreased the storage modulus （E＇）. However, the heat treatment resulted in an increase orE＇ of the wood flour/PP composites, with the temperature of loss factor peaks shifting to a higher temperature.展开更多
This study explores the coupling effect of pond ash(PA)and polypropylene(PP)fiber to control the strength and durability of expansive soil.The PA is used to chemically treat the expansive soil and PP fiber is adopted ...This study explores the coupling effect of pond ash(PA)and polypropylene(PP)fiber to control the strength and durability of expansive soil.The PA is used to chemically treat the expansive soil and PP fiber is adopted as reinforcement against tensile cracking.The sustainable use of PA and PP fiber are demonstrated by performing mechanical(i.e.unconfined compressive strength,split tensile strength and ultrasonic pulse velocity),chemical(pH value,electrical conductivity and calcite content),and microstructural analyses before and after 2nd,4th,6th,8th and 10th freezing-thawing(F-T)cycles.Three curing methods with 7 d,14 d and 28 d curing periods are considered to reinforce the 5%,10%,15%and 20%PA-stabilized expansive soil with 0.25%,0.5%and 1%PP fiber.In order to develop predictive models for mechanical and durability parameters,the experimental data are processed utilizing artificial neural network(ANN),in association with the leave-one-out cross-validation(LOOCV)as a resampling method and three different activation functions.The mechanical and durability properties of the PA-stabilized expansive soil subgrades are increased with PP fiber reinforcement.The results of ANN modeling predict the mechanical properties perfectly,and the correlation coefficient(R)approaches up to 0.96.展开更多
Day by day worldwide use of plastics is increasing because of their light weight and durable characteristics. Waste plastics are major environmental problems all over the world. Waste plastics are not bio-degradable, ...Day by day worldwide use of plastics is increasing because of their light weight and durable characteristics. Waste plastics are major environmental problems all over the world. Waste plastics are not bio-degradable, it remains in the landfill for a long period of time causing vegetation and aquatic ecosystem dilemmas. Abandoned waste plastic thrown into the ocean causes friction of ocean waves and then broken down by sunlight into small pieces and takes the shape of plastic like soup. Aquatic organism mistakes the plastic soup as their food and can’t digest, either they die or through food chain it affects human health. To avoid severe environmental degradation problems of waste plastics some countries and big cities banned or restricted the use of plastic products. The worldwide generation of waste plastics is approximately 280 million tons/year. All most all of these waste plastics are dumped either in land or ocean. City municipalities spend huge amount of money each year just to dispose of these waste plastics into landfill because most waste plastics are not recycled. When the waste plastics are subjected to incineration, they release harmful toxic gas into the environment causing severe pollution. These waste plastics gradually enhance the hazardous environmental problems. Generally plastics are made from crude oil, however crude oil is a very limited natural resource and non-renewable. Every year millions of barrels of crude oil are to produce the waste plastics and when plastics are discarded after use the energy source is lost. A new developed technology plan minimizes the environment pollution problems simultaneously boost up energy sector by renovating the waste plastics into high energy content fuel. The produced fuel is obtained using a unique thermal degradation of waste plastics and converting them into hydrocarbon fuel like materials. Preliminary tests proved that this fuel burns cleaner and the production cost is very low. Unique production setup demonstrated to produce 93% fuel from waste plastic in the pilot scale. The Fuel produced has been tested and proven to work on majority types of internal combustion engines. This technology utilized can avoid waste plastic pollution problem worldwide by the implementation of newly developed technology. Through the utilization of the technology the use of reliable plastics won’t need to be banned and serve as a very reliable alternate source of energy. The technology will also help reduce a significant amount of import oil from foreign countries and help provide a steady economy.展开更多
Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile...Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile strength, flexural strength, Izod impact strength are examined. Scanning electron microscopy (SEM) and polarised light microscopy (PLM) are used to observe the surface and crystal morphology. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) tests verify the non compatibility of both polymers. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques are used to study the thermal behaviour of composites. The results manifest co-occurring spherulites for polyblends;indicating the composite to be a physical blend of continuous and dispersed phases, but on the other hand PP improves the tensile and flexural properties of HDPE.展开更多
文摘The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and the optimization of raw materials inspection,steel pipe surface pretreatments,and water cooling control on a coating application process.The coating properties meet ISO standard 21809 on buried or submerged 3PP pipelines used in the petroleum and natural gas industries.Differential scanning calorimetry and X-ray diffraction were used to analyze the crystallinities and grain sizes of polypropylene(PP)top coats with different cooling rates.Increasing the melt cooling rate reduces the crystallinity and grain size of the PP top coat and enhances its strength and toughness.
基金the National Natural Science Foundation of China(No.19632004 and 10172074)
文摘By applying the reinforcing and toughening effect of calcium carbonate （CaCO3） nanoparticles on polypropylene, foam sheets of good performance were successfully fabricated by extrusion. The equipment and conditions of the extrusion were explored. The mechanical properties of the produced foam sheets were tested. The effect of CaCO3 nano-particles on the mechanical properties and the cellular structure of the sheets was comprehensively studied. The experimental results show that the optimum content of CaCO3 nano-particles in the composite material was -4wt%. At this content, the nano-particles were well dispersed in the substrate, and the composite material had maximum tensile strength and impact strength. Surface treatment of the nano-particles only affected the impact strength of the composite material. CaCO3 micro-particles, on the other hand, showed little effect on the properties of the composite material when the micro-particles content was less than 5 wt%. At a content higher than 5wt%, the properties of the composite material significantly worsened.
基金supported by the National Natural Science Foundation of China (Grant No.30871966)
文摘In order to improve the dimensional stability of wood-polymer composites, wood flour pre-treated by polyethylene glycol （PEG） at two different concentrations and then thermally treated at 140℃, was used as raw material to produce wood flour/poly- propylene （PP） composites at a wood content of 40%. The structure of modified wood flour was analyzed with a scanning electron microscope （SEM） and its effect on the physical and mechanical properties of wood flour/PP composites was evaluated. The SEM results indicated the ＂bulking＂ effect of PEG on wood flour, which resulted in reduced water uptake. The combination of PEG and heat treatment further improved the moisture resistance of the composites. However, PEG modification had a negative effect on the flexural modulus of rupture （MOR） and the modulus of elasticity （MOE）; whereas heat treatment partly compensated for this reduc- tion. For dynamic mechanical properties, PEG treatment decreased the storage modulus （E＇）. However, the heat treatment resulted in an increase orE＇ of the wood flour/PP composites, with the temperature of loss factor peaks shifting to a higher temperature.
文摘This study explores the coupling effect of pond ash(PA)and polypropylene(PP)fiber to control the strength and durability of expansive soil.The PA is used to chemically treat the expansive soil and PP fiber is adopted as reinforcement against tensile cracking.The sustainable use of PA and PP fiber are demonstrated by performing mechanical(i.e.unconfined compressive strength,split tensile strength and ultrasonic pulse velocity),chemical(pH value,electrical conductivity and calcite content),and microstructural analyses before and after 2nd,4th,6th,8th and 10th freezing-thawing(F-T)cycles.Three curing methods with 7 d,14 d and 28 d curing periods are considered to reinforce the 5%,10%,15%and 20%PA-stabilized expansive soil with 0.25%,0.5%and 1%PP fiber.In order to develop predictive models for mechanical and durability parameters,the experimental data are processed utilizing artificial neural network(ANN),in association with the leave-one-out cross-validation(LOOCV)as a resampling method and three different activation functions.The mechanical and durability properties of the PA-stabilized expansive soil subgrades are increased with PP fiber reinforcement.The results of ANN modeling predict the mechanical properties perfectly,and the correlation coefficient(R)approaches up to 0.96.
文摘Day by day worldwide use of plastics is increasing because of their light weight and durable characteristics. Waste plastics are major environmental problems all over the world. Waste plastics are not bio-degradable, it remains in the landfill for a long period of time causing vegetation and aquatic ecosystem dilemmas. Abandoned waste plastic thrown into the ocean causes friction of ocean waves and then broken down by sunlight into small pieces and takes the shape of plastic like soup. Aquatic organism mistakes the plastic soup as their food and can’t digest, either they die or through food chain it affects human health. To avoid severe environmental degradation problems of waste plastics some countries and big cities banned or restricted the use of plastic products. The worldwide generation of waste plastics is approximately 280 million tons/year. All most all of these waste plastics are dumped either in land or ocean. City municipalities spend huge amount of money each year just to dispose of these waste plastics into landfill because most waste plastics are not recycled. When the waste plastics are subjected to incineration, they release harmful toxic gas into the environment causing severe pollution. These waste plastics gradually enhance the hazardous environmental problems. Generally plastics are made from crude oil, however crude oil is a very limited natural resource and non-renewable. Every year millions of barrels of crude oil are to produce the waste plastics and when plastics are discarded after use the energy source is lost. A new developed technology plan minimizes the environment pollution problems simultaneously boost up energy sector by renovating the waste plastics into high energy content fuel. The produced fuel is obtained using a unique thermal degradation of waste plastics and converting them into hydrocarbon fuel like materials. Preliminary tests proved that this fuel burns cleaner and the production cost is very low. Unique production setup demonstrated to produce 93% fuel from waste plastic in the pilot scale. The Fuel produced has been tested and proven to work on majority types of internal combustion engines. This technology utilized can avoid waste plastic pollution problem worldwide by the implementation of newly developed technology. Through the utilization of the technology the use of reliable plastics won’t need to be banned and serve as a very reliable alternate source of energy. The technology will also help reduce a significant amount of import oil from foreign countries and help provide a steady economy.
文摘Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile strength, flexural strength, Izod impact strength are examined. Scanning electron microscopy (SEM) and polarised light microscopy (PLM) are used to observe the surface and crystal morphology. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) tests verify the non compatibility of both polymers. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques are used to study the thermal behaviour of composites. The results manifest co-occurring spherulites for polyblends;indicating the composite to be a physical blend of continuous and dispersed phases, but on the other hand PP improves the tensile and flexural properties of HDPE.
