Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalance...Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalanced stress during the cooling process,and this unbalanced stress can be exploited to prepare naturally crimped fibers by spinning design.In this work,different types of polyamides(PAs)were selected for fabrication of the PA-based side-by-side bicomponent elastic fibers using melt spinning,and the structure development and performance of such bicomponent elastic fibers were studied.Meanwhile,thermoplastic PA elastomer(TPAE)with intrinsic elasticity was also used as one of the comparative materials.The block structure of the PA segment and the polyether segment in the TPAE molecule is the key to providing thermal shrinkage differences and forming a good interface structure.As a result,the crimp ratio of PA6/TPAE bicomponent elastic fiber is 7.23%,which is better than that of the currently commercialized T400 fiber(6.72%).The excellent crimp performance of PA6/TPAE bicomponent elastic fibers comes from the asymmetric distribution of the stress along the radial direction of the fibers during the cooling process,which is caused by the difference in thermal shrinkage between PA6 and TPAE.In addition,the crimp formability of the PA-based bicomponent elastic fibers could be improved by expanding the shrinkage stress through wet-heat treatment.The crimp ratio of PA6/TPAE bicomponent elastic fibers reaches the maximum(33.08%)after treatment at 100℃.At the same time,the fabric made of PA6/TPAE bicomponent elastic fibers has the excellent air and water vapor permeability,with an air permeability of 272.76 mm/s and a water vapor transmission rate of 406.71 g/(m^(2)·h).展开更多
The supermolecular structure and mechanical properties as well as the crimp behavior of theside-by-side polyamide (PA 66-C710) fibers are studied by means of density gradient method,sonic measurement,X-ray,diffractome...The supermolecular structure and mechanical properties as well as the crimp behavior of theside-by-side polyamide (PA 66-C710) fibers are studied by means of density gradient method,sonic measurement,X-ray,diffractometry,differential scanning calorimetry,crimp tester etc.fortheir as-spun fibers,drawn fibers,and boiling-water treated fibers.The effects of the processingand treatment conditions on the formation of the supermolecular structure and the crimp behaviorof the fibers are investigated and discussed in detail,also the crimp mechanism of the side-by-sidebicomponent fibers is proposed.From these results,it is shown that by adopting suitable spinningfinish,reasonable processing technology and optimal heat treatment conditions the side-by-sidebicomponent polyamide fibers with excellent crimp property,close to that of nylon texturizedstretch yarns,can be obtained.展开更多
An attempt was made to numerically compute the temperature profile within the melt spinning of sheath core bicomponent fibers by deriving a set of simultaneous partial differential equations. The effects of accelerati...An attempt was made to numerically compute the temperature profile within the melt spinning of sheath core bicomponent fibers by deriving a set of simultaneous partial differential equations. The effects of acceleration, gravity, and air friction on the kinetics of the polymer were included and the upper-convected Maxwell model as the constitutive equation was adopted in this model.The sheath- core bicomponent fibers were partitioned intb a serial of circular cross section and it is assumed that each circular cross section has a temperature gradient while conducting the equation of energy balance. A mathematical model was developed to describe the melt spinning of sheath-core bicomponent fibers.展开更多
Highloft nonwoven was produced by heat bonding of bicomponent polyester fibers. The effect of fiber properties and processing parameters on the mechanical properties of the nonwoven was investigated. The heat bonding ...Highloft nonwoven was produced by heat bonding of bicomponent polyester fibers. The effect of fiber properties and processing parameters on the mechanical properties of the nonwoven was investigated. The heat bonding processing parameters for the nonwoven were optimized. The results show that the range of processing temperature is wider while the shell melting point of the bicomponent fibers (Tm1) is lower. The best processing temperature is about 15℃ higher than Tm1 while the shell melting point (Tm1) is higher.展开更多
PA6/PET bicomponent fiber at different spinning speedswere produced. Influences of cross blowing, spinning speed, PA6 and PET component ratio, drawing condition etc. on the mechanical properties, heat shrinkage,orient...PA6/PET bicomponent fiber at different spinning speedswere produced. Influences of cross blowing, spinning speed, PA6 and PET component ratio, drawing condition etc. on the mechanical properties, heat shrinkage,orientation and crystallization of the fiber were investigated. Also the rules among these influencing parameters were obtained. The splitting property of the fiber and its influence on the textile processing are discussed, which offers a base for the production of PA6/PET bicomponent fiber using splitting technology.展开更多
Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at ...Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at the laboratory scale. It remains a great challenge to use industrial spinning equipment to achieve continuous processing of TRF_(s) with excellent thermal and mechanical properties. Here, polyamide 6(PA6) based TRF_(s) with a sheath-core structure were prepared by bicomponent melt-spinning. The sheath-core TRF(TRF_(sc)) are composed of PA6 as sheath and functional PA6 as core, which are filled with the shape stable phase change materials(ssPCM),dendritic silica@polyethylene glycol(SiO_(2)@PEG). With the aid of the sheath structure, the filling content of SiO_(2)@PEG can reach 30 %, so that the enthalpy of the TRF_(s) can be as high as 21.3 J/g. The ultra-high enthalpy guarantees the temperature regulation ability during the alternating process of cooling and heating. In hot environment, the temperature regulation time is 6.59 min, and the temperature difference is 12.93℃. In addition, the mechanical strength of the prepared TRF_(sc) reaches 2.26 cN/dtex, which can fully meet its application in the field of thermal management textiles and devices to manage the temperature regulation of the human body or precision equipment, etc.展开更多
Stretchable conductive fibers offer unparalleled advantages in the development of wearable strain sensors for smart textiles due to their excellent flexibility and weaveability.However,the practical applications of th...Stretchable conductive fibers offer unparalleled advantages in the development of wearable strain sensors for smart textiles due to their excellent flexibility and weaveability.However,the practical applications of these fibers in wearable devices are hindered by either contradictory properties of conductive fibers(high stretchability versus high sensing stability),or lack of manufacturing scalability.Herein,we present a facile approach for highly stretchable self-crimping fiber strain sensors based on a polyether-ester(TPEE)elastomer matrix using a side-by-side bicomponent melt-spinning process involving two parallel but attached components with different shrinkage properties.The TPEE component serves as a highly elastic mechanical support layer within the bicomponent fibers,while the conductive component(E-TPEE)of carbon black(CB),multiwalled carbon nanotubes(MWCNTs)and TPEE works as a strain-sensitive layer.In addition to the intrinsic elasticity of the matrix,theTPEE/E-TPEE bicomponent fibers present an excellent form of elasticity due to self-crimping.The self-crimping elongation of the fibers can provide a large deformation,and after the crimp disappears,the intrinsic elastic deformation is responsible for monitoring the strain sensing.The reliable strain sensing range of theTPEE/E-TPEE composite fibers was 160%-270%and could be regulated by adjusting the crimp structure.More importantly,the TPEE/E-TPEE fibers had a diameter of 30-40 pm and tenacity of 40-50 MPa,showing the necessary practicality.This work introduces new possibilities for fiber strain sensors produced in standard industrial spinning machines.展开更多
基金Fundamental Research Funds for the Central Universities of China(No.2232022D-10)Open Fund of State Key Laboratory of Biobased Fiber Manufacturing Technology,China(No.SKL202306)。
文摘Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalanced stress during the cooling process,and this unbalanced stress can be exploited to prepare naturally crimped fibers by spinning design.In this work,different types of polyamides(PAs)were selected for fabrication of the PA-based side-by-side bicomponent elastic fibers using melt spinning,and the structure development and performance of such bicomponent elastic fibers were studied.Meanwhile,thermoplastic PA elastomer(TPAE)with intrinsic elasticity was also used as one of the comparative materials.The block structure of the PA segment and the polyether segment in the TPAE molecule is the key to providing thermal shrinkage differences and forming a good interface structure.As a result,the crimp ratio of PA6/TPAE bicomponent elastic fiber is 7.23%,which is better than that of the currently commercialized T400 fiber(6.72%).The excellent crimp performance of PA6/TPAE bicomponent elastic fibers comes from the asymmetric distribution of the stress along the radial direction of the fibers during the cooling process,which is caused by the difference in thermal shrinkage between PA6 and TPAE.In addition,the crimp formability of the PA-based bicomponent elastic fibers could be improved by expanding the shrinkage stress through wet-heat treatment.The crimp ratio of PA6/TPAE bicomponent elastic fibers reaches the maximum(33.08%)after treatment at 100℃.At the same time,the fabric made of PA6/TPAE bicomponent elastic fibers has the excellent air and water vapor permeability,with an air permeability of 272.76 mm/s and a water vapor transmission rate of 406.71 g/(m^(2)·h).
文摘The supermolecular structure and mechanical properties as well as the crimp behavior of theside-by-side polyamide (PA 66-C710) fibers are studied by means of density gradient method,sonic measurement,X-ray,diffractometry,differential scanning calorimetry,crimp tester etc.fortheir as-spun fibers,drawn fibers,and boiling-water treated fibers.The effects of the processingand treatment conditions on the formation of the supermolecular structure and the crimp behaviorof the fibers are investigated and discussed in detail,also the crimp mechanism of the side-by-sidebicomponent fibers is proposed.From these results,it is shown that by adopting suitable spinningfinish,reasonable processing technology and optimal heat treatment conditions the side-by-sidebicomponent polyamide fibers with excellent crimp property,close to that of nylon texturizedstretch yarns,can be obtained.
文摘An attempt was made to numerically compute the temperature profile within the melt spinning of sheath core bicomponent fibers by deriving a set of simultaneous partial differential equations. The effects of acceleration, gravity, and air friction on the kinetics of the polymer were included and the upper-convected Maxwell model as the constitutive equation was adopted in this model.The sheath- core bicomponent fibers were partitioned intb a serial of circular cross section and it is assumed that each circular cross section has a temperature gradient while conducting the equation of energy balance. A mathematical model was developed to describe the melt spinning of sheath-core bicomponent fibers.
文摘Highloft nonwoven was produced by heat bonding of bicomponent polyester fibers. The effect of fiber properties and processing parameters on the mechanical properties of the nonwoven was investigated. The heat bonding processing parameters for the nonwoven were optimized. The results show that the range of processing temperature is wider while the shell melting point of the bicomponent fibers (Tm1) is lower. The best processing temperature is about 15℃ higher than Tm1 while the shell melting point (Tm1) is higher.
文摘PA6/PET bicomponent fiber at different spinning speedswere produced. Influences of cross blowing, spinning speed, PA6 and PET component ratio, drawing condition etc. on the mechanical properties, heat shrinkage,orientation and crystallization of the fiber were investigated. Also the rules among these influencing parameters were obtained. The splitting property of the fiber and its influence on the textile processing are discussed, which offers a base for the production of PA6/PET bicomponent fiber using splitting technology.
基金financially supported by the National Natural Science Foundation of China (52073047)the Science and Technology Commission of Shanghai Municipality (20JC1414900)+1 种基金the Program of Shanghai Technology Research Leader (20XD1433700)the INTERNATIONAL COOPERATION Fund of the Science and Technology Commission of Shanghai Municipality (20520740800)。
文摘Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at the laboratory scale. It remains a great challenge to use industrial spinning equipment to achieve continuous processing of TRF_(s) with excellent thermal and mechanical properties. Here, polyamide 6(PA6) based TRF_(s) with a sheath-core structure were prepared by bicomponent melt-spinning. The sheath-core TRF(TRF_(sc)) are composed of PA6 as sheath and functional PA6 as core, which are filled with the shape stable phase change materials(ssPCM),dendritic silica@polyethylene glycol(SiO_(2)@PEG). With the aid of the sheath structure, the filling content of SiO_(2)@PEG can reach 30 %, so that the enthalpy of the TRF_(s) can be as high as 21.3 J/g. The ultra-high enthalpy guarantees the temperature regulation ability during the alternating process of cooling and heating. In hot environment, the temperature regulation time is 6.59 min, and the temperature difference is 12.93℃. In addition, the mechanical strength of the prepared TRF_(sc) reaches 2.26 cN/dtex, which can fully meet its application in the field of thermal management textiles and devices to manage the temperature regulation of the human body or precision equipment, etc.
基金the Prospective Applied Basic Research Program of Suzhou City(No.SYG202041)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.19KJB540004)+1 种基金Jiangsu Postdoctoral Science Foundation(No.2020Z159)China Postdoctoral Science Foundation(No.2017M620125).
文摘Stretchable conductive fibers offer unparalleled advantages in the development of wearable strain sensors for smart textiles due to their excellent flexibility and weaveability.However,the practical applications of these fibers in wearable devices are hindered by either contradictory properties of conductive fibers(high stretchability versus high sensing stability),or lack of manufacturing scalability.Herein,we present a facile approach for highly stretchable self-crimping fiber strain sensors based on a polyether-ester(TPEE)elastomer matrix using a side-by-side bicomponent melt-spinning process involving two parallel but attached components with different shrinkage properties.The TPEE component serves as a highly elastic mechanical support layer within the bicomponent fibers,while the conductive component(E-TPEE)of carbon black(CB),multiwalled carbon nanotubes(MWCNTs)and TPEE works as a strain-sensitive layer.In addition to the intrinsic elasticity of the matrix,theTPEE/E-TPEE bicomponent fibers present an excellent form of elasticity due to self-crimping.The self-crimping elongation of the fibers can provide a large deformation,and after the crimp disappears,the intrinsic elastic deformation is responsible for monitoring the strain sensing.The reliable strain sensing range of theTPEE/E-TPEE composite fibers was 160%-270%and could be regulated by adjusting the crimp structure.More importantly,the TPEE/E-TPEE fibers had a diameter of 30-40 pm and tenacity of 40-50 MPa,showing the necessary practicality.This work introduces new possibilities for fiber strain sensors produced in standard industrial spinning machines.
