The risk of leakage and low thermal conductivity severely hinder the wide application of phase change materials(PCMs).In this work,the high-density polyethylene/carbon nanotubes(HDPE/CNTs)porous scaffolds were success...The risk of leakage and low thermal conductivity severely hinder the wide application of phase change materials(PCMs).In this work,the high-density polyethylene/carbon nanotubes(HDPE/CNTs)porous scaffolds were successfully fabricated via a sacrificial template method followed by the general melt blending and water solvent etching.Subsequently,a series of paraffin wax HDPE/CNTs/PW composite PCMs were obtained combined with the simple vacuum impregnation method.The obtained HDPE/CNTs porous scaffolds can effectively avoid the leakage of PW,meanwhile,the thermal conductivity and electrical conductivity of HDPE/CNTs/PW-3:7 are increased by 2.94 times and 13 orders of magnitude compared with the HDPE/PW-3:7 respectively,also,it exhibits high phase change enthalpy(153.95 J/g for melting enthalpy and 152.82 J/g for crystallization enthalpy).From the above perspectives,the HDPE/CNTs/PW-3:7 has promising potential value in the application of light-to-thermal conversion,electro-to-thermal conversion and thermal energy storage.展开更多
Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were ...Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C;suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C.展开更多
In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- ti...In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes.展开更多
An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-tr...An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>26 MPa), break elongation (<1.1%), flexural strength (>22 MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite.展开更多
HDPE管(全称High Density Polyethylene,高密度聚乙烯管)具有耐腐蚀、耐低温、轻质高强、连接可靠等核心优势,目前广泛应用于海上取排水口设计中。由于其质量轻,通常需要压载块助沉。混凝土块是常见的压载块,然而目前尚无统一的标准阐...HDPE管(全称High Density Polyethylene,高密度聚乙烯管)具有耐腐蚀、耐低温、轻质高强、连接可靠等核心优势,目前广泛应用于海上取排水口设计中。由于其质量轻,通常需要压载块助沉。混凝土块是常见的压载块,然而目前尚无统一的标准阐述如何设置压载块个数。如果混凝土块设置过多,将导致起吊困难,同时造成不必要的施工费用增加,如果设置过少,将起不到助沉的效果,因此,合理设置混凝土块对于HDPE管的安装显得尤为重要。本文以湛江某项目排水口工程为例,详细论述了HDPE管压载块数量的计算。展开更多
将改性磷石膏晶须与高密度聚乙烯(High density polyethylene,HDPE)进行共混,通过注塑成型技术制备HDPE/磷石膏晶须复合材料,采用傅立叶转换红外光谱(FI-IR)、扫描电镜(SEM)、热分析(DSC)等技术,分析改性磷石膏晶须对HDPE复合材料力学...将改性磷石膏晶须与高密度聚乙烯(High density polyethylene,HDPE)进行共混,通过注塑成型技术制备HDPE/磷石膏晶须复合材料,采用傅立叶转换红外光谱(FI-IR)、扫描电镜(SEM)、热分析(DSC)等技术,分析改性磷石膏晶须对HDPE复合材料力学性能的影响。结果表明:改性后HDPE/磷石膏晶须复合材料的冲击强度、拉伸强度和弯曲强度分别为44.33 k J/m2、25.54 MPa和473.5 MPa,与纯HDPE相比,相应提高了31.5%、6.64%和25.15%;与未改性HDPE/磷石膏晶须复合材料相比,冲击强度提高69.13%,拉伸强度与弯曲强度分别降低1.28%和9.65%。故改性后HDPE/磷石膏晶须的综合性能较好。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51903092)support from Guangdong Special Support Program(Grant No.2017TX04N371)。
文摘The risk of leakage and low thermal conductivity severely hinder the wide application of phase change materials(PCMs).In this work,the high-density polyethylene/carbon nanotubes(HDPE/CNTs)porous scaffolds were successfully fabricated via a sacrificial template method followed by the general melt blending and water solvent etching.Subsequently,a series of paraffin wax HDPE/CNTs/PW composite PCMs were obtained combined with the simple vacuum impregnation method.The obtained HDPE/CNTs porous scaffolds can effectively avoid the leakage of PW,meanwhile,the thermal conductivity and electrical conductivity of HDPE/CNTs/PW-3:7 are increased by 2.94 times and 13 orders of magnitude compared with the HDPE/PW-3:7 respectively,also,it exhibits high phase change enthalpy(153.95 J/g for melting enthalpy and 152.82 J/g for crystallization enthalpy).From the above perspectives,the HDPE/CNTs/PW-3:7 has promising potential value in the application of light-to-thermal conversion,electro-to-thermal conversion and thermal energy storage.
文摘Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C;suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C.
文摘In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes.
文摘An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>26 MPa), break elongation (<1.1%), flexural strength (>22 MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite.
文摘HDPE管(全称High Density Polyethylene,高密度聚乙烯管)具有耐腐蚀、耐低温、轻质高强、连接可靠等核心优势,目前广泛应用于海上取排水口设计中。由于其质量轻,通常需要压载块助沉。混凝土块是常见的压载块,然而目前尚无统一的标准阐述如何设置压载块个数。如果混凝土块设置过多,将导致起吊困难,同时造成不必要的施工费用增加,如果设置过少,将起不到助沉的效果,因此,合理设置混凝土块对于HDPE管的安装显得尤为重要。本文以湛江某项目排水口工程为例,详细论述了HDPE管压载块数量的计算。
文摘将改性磷石膏晶须与高密度聚乙烯(High density polyethylene,HDPE)进行共混,通过注塑成型技术制备HDPE/磷石膏晶须复合材料,采用傅立叶转换红外光谱(FI-IR)、扫描电镜(SEM)、热分析(DSC)等技术,分析改性磷石膏晶须对HDPE复合材料力学性能的影响。结果表明:改性后HDPE/磷石膏晶须复合材料的冲击强度、拉伸强度和弯曲强度分别为44.33 k J/m2、25.54 MPa和473.5 MPa,与纯HDPE相比,相应提高了31.5%、6.64%和25.15%;与未改性HDPE/磷石膏晶须复合材料相比,冲击强度提高69.13%,拉伸强度与弯曲强度分别降低1.28%和9.65%。故改性后HDPE/磷石膏晶须的综合性能较好。
