UHMWPE fibers exhibit impressive modulus and strength,but they have not reached their theoretical limits.Researchers focus on molecular weight,orientation,and crystallinity of UHMWPE,yet their contributions to mechani...UHMWPE fibers exhibit impressive modulus and strength,but they have not reached their theoretical limits.Researchers focus on molecular weight,orientation,and crystallinity of UHMWPE,yet their contributions to mechanical properties are unclear.Molecular dynamics simulations are valuable but often limited by computational constraints.Our aim is to simulate higher molecular weights to better represent real UHMWPE fibers.We used Packmol and Polyply methodologies to construct PE systems,with Polyply reproducing more reasonable properties of UHMWPE fibers.Additionally,tensile simulations showed that orientation and crystallinity greatly impact Young's modulus more than molecular weight.Energy decomposition indicated that higher molecular weights lead to covalent bonds that can withstand more energy during stretching,thus increasing breaking strength.Combining simulations with machine learning,we found that orientation has the most significant impact on Young's modulus,contributing 60%,and molecular weight plays the most crucial role in determining the breaking strength,accounting for 65%.This study provides a theoretical basis and guidelines for enhancing UHMWPE's modulus and strength.展开更多
Purpose of this novel review article is to unfold the current scientific worth of high performance polymer nanocomposite nanofibers,owing to growing scientific interests in this field.Accordingly,this state-of-the-art...Purpose of this novel review article is to unfold the current scientific worth of high performance polymer nanocomposite nanofibers,owing to growing scientific interests in this field.Accordingly,this state-of-the-art manuscript has been systematically categorized into distinct sections related to(i)fundamentals of carbonaceous nanoreinforcements,(ii)design-structure-property-performance aspects of different categories of polymer nanocomposite nanofibers(conducting polymers,thermoplastics,and thermosets with carbonaceous nanofillers carbon nanotubes,graphene,fullerene),and then(iii)existing scientific worth(energy devices,electronics,space/defense,environmental sectors),future prospects,challenges,and conclusions.As per literature to date,polymer/carbonaceous nanocomposite nanofibers had myriad of advantageous physical characters(morphologies,electrical/charge conduction,thermal conduction,mechanical/thermal resistance,anticorrosion,permeability,radiation absorption).Notably,among conducting polymer nanofibers,polyaniline/carbon nanotube nanofibers revealed superior specific capacitance(~380 Fg^(-1))due to interfacial synergies and electron/charge transfer.Moreover,poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester/fullerene nanofibers revealed power conversion efficiency~3.6%.Out of thermoplastic systems,poly(vinyl alcohol)/carbon nanotube nanofibers have been designed for piezoelectric sensors(pressure sensitivity~0.28 kPa^(-1))and toxicmetal ion sensors(lead(II)).In addition,cellulose/carbonaceous nanocomposite nanofibers have been applied for supercapacitor electrodes(specific capacitance~250 Fg^(-1))and electromagnetic interference shielding effectiveness(~64-70 dB).Furthermore,epoxy/carbon nanotube nanocomposites revealed~20%-40% enhancements in tensile strength and shear strength due to load transfer properties.As per literature,technological performance of these materials depends upon types/amount of polymers,nanocarbons,and processing methods/parameters used.Owing to novelty of topic,outline,and literature coverage,this review will serve as an all-inclusive guide for concerned field researchers to carry out further industrial scale advancements in the field of nanocomposite nanofibers.展开更多
A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark...A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark rivers from the winding machines.The Institute of Coal Chemistry of the Chinese Academy of Sciences(CAS)developed T1000-grade high-performance carbon fiber here,and it has fully independent intellectual property rights.“It took us 20 years to go from having‘no grain to cook’to achieving‘high-end iteration,’”said Zhang Shouchun,Deputy Director of the Institute of Coal Chemistry,CAS,and project leader.Behind this striking black thread lies an arduous,persistent campaign of material innovation.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52303298 and 52233002)。
文摘UHMWPE fibers exhibit impressive modulus and strength,but they have not reached their theoretical limits.Researchers focus on molecular weight,orientation,and crystallinity of UHMWPE,yet their contributions to mechanical properties are unclear.Molecular dynamics simulations are valuable but often limited by computational constraints.Our aim is to simulate higher molecular weights to better represent real UHMWPE fibers.We used Packmol and Polyply methodologies to construct PE systems,with Polyply reproducing more reasonable properties of UHMWPE fibers.Additionally,tensile simulations showed that orientation and crystallinity greatly impact Young's modulus more than molecular weight.Energy decomposition indicated that higher molecular weights lead to covalent bonds that can withstand more energy during stretching,thus increasing breaking strength.Combining simulations with machine learning,we found that orientation has the most significant impact on Young's modulus,contributing 60%,and molecular weight plays the most crucial role in determining the breaking strength,accounting for 65%.This study provides a theoretical basis and guidelines for enhancing UHMWPE's modulus and strength.
文摘Purpose of this novel review article is to unfold the current scientific worth of high performance polymer nanocomposite nanofibers,owing to growing scientific interests in this field.Accordingly,this state-of-the-art manuscript has been systematically categorized into distinct sections related to(i)fundamentals of carbonaceous nanoreinforcements,(ii)design-structure-property-performance aspects of different categories of polymer nanocomposite nanofibers(conducting polymers,thermoplastics,and thermosets with carbonaceous nanofillers carbon nanotubes,graphene,fullerene),and then(iii)existing scientific worth(energy devices,electronics,space/defense,environmental sectors),future prospects,challenges,and conclusions.As per literature to date,polymer/carbonaceous nanocomposite nanofibers had myriad of advantageous physical characters(morphologies,electrical/charge conduction,thermal conduction,mechanical/thermal resistance,anticorrosion,permeability,radiation absorption).Notably,among conducting polymer nanofibers,polyaniline/carbon nanotube nanofibers revealed superior specific capacitance(~380 Fg^(-1))due to interfacial synergies and electron/charge transfer.Moreover,poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester/fullerene nanofibers revealed power conversion efficiency~3.6%.Out of thermoplastic systems,poly(vinyl alcohol)/carbon nanotube nanofibers have been designed for piezoelectric sensors(pressure sensitivity~0.28 kPa^(-1))and toxicmetal ion sensors(lead(II)).In addition,cellulose/carbonaceous nanocomposite nanofibers have been applied for supercapacitor electrodes(specific capacitance~250 Fg^(-1))and electromagnetic interference shielding effectiveness(~64-70 dB).Furthermore,epoxy/carbon nanotube nanocomposites revealed~20%-40% enhancements in tensile strength and shear strength due to load transfer properties.As per literature,technological performance of these materials depends upon types/amount of polymers,nanocarbons,and processing methods/parameters used.Owing to novelty of topic,outline,and literature coverage,this review will serve as an all-inclusive guide for concerned field researchers to carry out further industrial scale advancements in the field of nanocomposite nanofibers.
文摘A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark rivers from the winding machines.The Institute of Coal Chemistry of the Chinese Academy of Sciences(CAS)developed T1000-grade high-performance carbon fiber here,and it has fully independent intellectual property rights.“It took us 20 years to go from having‘no grain to cook’to achieving‘high-end iteration,’”said Zhang Shouchun,Deputy Director of the Institute of Coal Chemistry,CAS,and project leader.Behind this striking black thread lies an arduous,persistent campaign of material innovation.
