Polyethylene terephthalate(PET)fibers are the largest category of chemical fibers and are widely used.However,the dyeing of PET fibers requires high temperature and pressure(130℃and 0.2 MPa),and the dyeing process co...Polyethylene terephthalate(PET)fibers are the largest category of chemical fibers and are widely used.However,the dyeing of PET fibers requires high temperature and pressure(130℃and 0.2 MPa),and the dyeing process consumes huge amounts of energy.Existing studies have shown that the dyeing ability of PET is directly related to the size of the amorphous region,which determines the external conditions for dyeing.In this research,we synthesized a series of low-temperature easydyeing masterbatches,PET-co-polyethylene glycol(PETEG),using polyethylene glycol(PEG)with different number-average molecular masses Mn and additive amounts.The phase domain size of the amorphous region of PET fibers was regulated via the masterbatch method.The relationship between the phase domain size and dyeing performance was explored from three perspectives:the amount of masterbatch,type of masterbatch,and PEG relative molecular mass.The results indicate that the fiber sample with PEG(Mn=2000 g/mol)at a mass fraction of 20%modified masterbatch has a smaller crystalline lamellar thickness(5.59 nm)and a larger interlamellar amorphous layer thickness(6.43 nm).The increase in the long period and lamellar inclination angle results in a looser structure,allowing small molecule dyes to diffuse into the fibers more easily.The dye-uptake increases from 63.21%to 92.66%at 100℃with the addition of the masterbatch.Additionally,the dye-uptake of the modified fibers increases with the relative molecular mass of PEG and the mass fraction of the masterbatch.All modified fibers achieve a staining color fastness of grade 4 or higher.This research demonstrates a simple masterbatch method that enables atmospheric pressure dyeing and provides a practical solution for efficient,low-temperature,and low-energy dyeing of PET fibers.展开更多
Nano-silica treated with different kinds of coupling agent （KH550, A-143, A-151） was used to modify the surface condition of glass fiber, and then, the modified glass fiber/unsaturated polyester resin （UPR） compos...Nano-silica treated with different kinds of coupling agent （KH550, A-143, A-151） was used to modify the surface condition of glass fiber, and then, the modified glass fiber/unsaturated polyester resin （UPR） composites materials were prepared. Scanning electron microscopy （SEM）, dynamic mechanical analysis （DMA）, and impact test were used to characterize the composite materials＇ structure and properties. The morphology of composite materials shows that the adhesion between nano-silica and glass fiber is improved when silane coupling agent is added in. The DMA and impact test results show that silane coupling agent （especially KH550 and A-151） could effectively improve the composite＇s mechanical properties. When the dose of KH550 was 0.1% （m ： m）, the storage modulus and impact strength reached the maximum.展开更多
The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of dra...The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry weight.Results indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by nanoclay.In addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.展开更多
Abstract A newly developed coaxial dielectric barrier discharge reactor with a length of 1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord in a roll-to-roll manner. In this react...Abstract A newly developed coaxial dielectric barrier discharge reactor with a length of 1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord in a roll-to-roll manner. In this reactor, swirling mixture gases of oxygen of about 1% and argon with a flow rate of 1.5 L/rain to 2.7 L/min ensured the gas usage sparing, discharge uniformity and efficient fiber surface modification. The water contact angle and surface morphology of the treated fiber were measured. The results show that the surface oxygenation is mainly responsible for the wettability improvement of the fiber cord when passing through the plasma zone at a linear speed of 3 m/min to 8 m/rain. The specimens of modified-polyester fiber reinforced rubber composite were also prepared for the interracial shear strength tests. Furthermore, the effect of adding oxygen into argon discharge on the fiber surface oxidation was correlated with optical emission spectroscopy. Finally, the effect of adding oxygen into argon discharge on the kinetic processes of the active species generation were also analyzed.展开更多
Improvement in synthetic fiber based composites is a hot topic in the material area.The incompatibility between the surfaces of synthetic fibers is a significant challenge due to fibers hydrophobic property.In this st...Improvement in synthetic fiber based composites is a hot topic in the material area.The incompatibility between the surfaces of synthetic fibers is a significant challenge due to fibers hydrophobic property.In this study,PET(polyethylene terephthalate) fibers based on low hydrophilic were slightly treated with NaOH or sodium dodecyl benzene sulfonate(SDBS).SEM images showed that there were some pits on the surface of PET fibers treated by NaOH,while PET fibers treated by SDBS became smoother.The peaks at 3725 cm^(-1) and 3628 cm^(-1) were generated for PET fibers treated by NaOH,which was attributed to—OH produced from the ester group hydrolysis,but no same peak is shown for the treated ones by SDBS.Meanwhile,the crystallinity indices of the treated PET fibers slightly decreased.Compared with original PET fibers,the formation of sheet made from PET fibers treated by NaOH became worse,but that from SDBS treated PET fibers became better.展开更多
Modified polyester fibers were obtained using 2% and 6% of kaolin blends through melt spinning.The influences of two thermal treatments maintaining the original tension(180 ℃×2 min and 200 ℃×1 min)on the s...Modified polyester fibers were obtained using 2% and 6% of kaolin blends through melt spinning.The influences of two thermal treatments maintaining the original tension(180 ℃×2 min and 200 ℃×1 min)on the structure and properties of fiber were compared.The changes of grain size and crystallinity of fiber were investigated by X-ray diffraction(XRD).The changes of thermal properties of fibers were analyzed using dynamic mechanical analyzer(DMA).The results show that the crystalline structure of kaolin modified polyester fiber doesn't change with the thermal treatment.With the kaolin content increasing,the grain size of fiber changed.The higher the thermal treatment temperature is,the higher the crystallinity of fiber is.There are two glass-transition temperatures for kaolin modified:the lower one is the glass-transition temperature of polyester fiber matrix,and the higher one is derived from the heterogeneous blend of polyester matrix and nano kaolin.The higher the kaolin content is,the higher the glass-transition temperature is.Thermal treatment could increase the compatibility of polyester matrix and nano kaolin.There was only one glass-transition temperature for the thermal treatment fiber,and the heat resistance of fiber was improved.Thermogravimetric analysis-differential scanning calorimetry(TGA-DSC)results of kaolin modified polyethylene terephthalate(PET)matrix indicate that the decomposition temperature of PET fibers,kaolin modified PET fibers,and thermal treated fibers were little different within 40%-60% of weight loss rate range.展开更多
The degradation of diethylene glycol terephthalate (DTP) and polyethylene terephthalate (PET) fiber by microbe was studied.The degree of DTP degradation was determined by High Performance Liquid Chromatography (HPLC) ...The degradation of diethylene glycol terephthalate (DTP) and polyethylene terephthalate (PET) fiber by microbe was studied.The degree of DTP degradation was determined by High Performance Liquid Chromatography (HPLC) to be more than 90%.The products after degradation of DTP and PET fiber were various.The degradation of DTP can be described by the first-order reaction model.The degradation of PET fiber was found to be little,but surface erosion of PET fiber could be clearly seen from the SEM photographs indicating there occurred some traces of biodegradation on the PET fiber surface.展开更多
In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optic...In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optical diagnostics.It is found that the interfacial adhesion strength between treated PET fiber and resorcinol formaldehyde latex(RFL)(little)-rubber was improved(about 50%) by the measurement of interfacial shear strength(IFSS) and peel test.The wettability was improved rapidly in the initial treatment time.It is considered that oxidation chemical reaction as the major role of PET fiber surface modification is ahead of the physical etching effect.The high density of atomic oxygen in the plasma by optical emission spectroscopy supports the purpose.According to the scanning electron micrograph(SEM) image in the work,the longer treatment time obviously caused physical etching effect,which shall be less responsible for the improvement of the wettability.展开更多
Reversible addition-fragmentation chain transfer(RAFT) mediated grafting of acrylonitrile onto Polyethylene/Poly(ethylene terephthalate)(PE/PET) composite fibers was performed using γ-irradiation as the initial sourc...Reversible addition-fragmentation chain transfer(RAFT) mediated grafting of acrylonitrile onto Polyethylene/Poly(ethylene terephthalate)(PE/PET) composite fibers was performed using γ-irradiation as the initial source at ambient temperature. Different initial concentrations of 2-cyanoprop-2-yl dithiobenzonate were used as the chain transfer agent. The kinetics of graft polymerization is in accordance with the living RAFT polymerization. The successful grafting of acrylonitrile is proved by Fourier transform infrared spectroscopy analysis.The results of monofilament tensile test show that mechanical properties of the fibers change slightly after grafting. Scanning electronic microscopy images of the fibers show that the surface of RAFT grafted fibers is smoother than that of fibers grafted conventionally.展开更多
Cation Dyeable Polyester(CDP)was made by copolymerizing dimethyl terephthalate(DMT),S-sodium sulfonate dimethyl isophthalate(SIPM) with a weight fraction of 4.5% and ethyleneglycol (EG).Blend of PET and CDP was spun i...Cation Dyeable Polyester(CDP)was made by copolymerizing dimethyl terephthalate(DMT),S-sodium sulfonate dimethyl isophthalate(SIPM) with a weight fraction of 4.5% and ethyleneglycol (EG).Blend of PET and CDP was spun into hollow fiber.The fiber was then treated withaqueous NaOH.In this paper,kinetics and mechanism of alkaline hydrolysis of PET,CDP andtheir blend PET/CDP fiber were studied by means of specific area measurement,scantling elec-tron microscopy and other chemical analyses.It was showed that the rate of alkaline hydrolysis isCDP】PET/CDP】PET.Because of blending effect,the alkaline hydrolysis of PET/CDP is dif-ferent from that of PET.CDP phase in the PET/CDP fiber is predominantly hydrolyzed,andhence some pieces of fiber(micro-fiber) fall off the fiber because of etching.展开更多
为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行...为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。展开更多
This paper deals with the fracture feature of three kinds of polyester fibers with differentstructures under different tensile conditions.We studied fracture initiation,crack propagationand ultimate fracture character...This paper deals with the fracture feature of three kinds of polyester fibers with differentstructures under different tensile conditions.We studied fracture initiation,crack propagationand ultimate fracture characteristics under tension of polyester fibers.The fracture features ofpolyester fibers are related with fiber structure and tensile condition.Crack is initiated in fibersurface.It propagates from outside to inside and eventually causes rupture of the fiber.In addi-tion,it is stated also that the analysis on tensile fracture feature of fibers might be confirmed bydynamic testing technique of scanning electron microscopy.展开更多
Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester （PP/EHDPET） blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub&g...Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester （PP/EHDPET） blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub>O solu-tion. We investigated the morphology of PP/EHDPETblend fibers before and after stretching and alkalinehydrolysis. Then thermal behavior of the blend has alsobeen studied.展开更多
Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copo...Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copolyester that can be rapidly hydro-degraded in the hot alkaline solution. This paper discussed the kinetics of alkaline hydrolysis of EHDPET, and the effect of catalyst, bulk ratio and the content of polypropylene grafted maleic anhydride (PP-g-MAH) on the alkaline hydrolysis process. Meanwhile, the morphological change of the outer surface of blend fibers during this process was also investigated by the technology of scanning electron microscope (SEM).展开更多
基金Key R&D Program of the Xinjiang Uygur Autonomous Region,China(No.2024B01011)。
文摘Polyethylene terephthalate(PET)fibers are the largest category of chemical fibers and are widely used.However,the dyeing of PET fibers requires high temperature and pressure(130℃and 0.2 MPa),and the dyeing process consumes huge amounts of energy.Existing studies have shown that the dyeing ability of PET is directly related to the size of the amorphous region,which determines the external conditions for dyeing.In this research,we synthesized a series of low-temperature easydyeing masterbatches,PET-co-polyethylene glycol(PETEG),using polyethylene glycol(PEG)with different number-average molecular masses Mn and additive amounts.The phase domain size of the amorphous region of PET fibers was regulated via the masterbatch method.The relationship between the phase domain size and dyeing performance was explored from three perspectives:the amount of masterbatch,type of masterbatch,and PEG relative molecular mass.The results indicate that the fiber sample with PEG(Mn=2000 g/mol)at a mass fraction of 20%modified masterbatch has a smaller crystalline lamellar thickness(5.59 nm)and a larger interlamellar amorphous layer thickness(6.43 nm).The increase in the long period and lamellar inclination angle results in a looser structure,allowing small molecule dyes to diffuse into the fibers more easily.The dye-uptake increases from 63.21%to 92.66%at 100℃with the addition of the masterbatch.Additionally,the dye-uptake of the modified fibers increases with the relative molecular mass of PEG and the mass fraction of the masterbatch.All modified fibers achieve a staining color fastness of grade 4 or higher.This research demonstrates a simple masterbatch method that enables atmospheric pressure dyeing and provides a practical solution for efficient,low-temperature,and low-energy dyeing of PET fibers.
基金Supported by the National Natural Science Foundation of of China(J1210061)
文摘Nano-silica treated with different kinds of coupling agent （KH550, A-143, A-151） was used to modify the surface condition of glass fiber, and then, the modified glass fiber/unsaturated polyester resin （UPR） composites materials were prepared. Scanning electron microscopy （SEM）, dynamic mechanical analysis （DMA）, and impact test were used to characterize the composite materials＇ structure and properties. The morphology of composite materials shows that the adhesion between nano-silica and glass fiber is improved when silane coupling agent is added in. The DMA and impact test results show that silane coupling agent （especially KH550 and A-151） could effectively improve the composite＇s mechanical properties. When the dose of KH550 was 0.1% （m ： m）, the storage modulus and impact strength reached the maximum.
文摘The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry weight.Results indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by nanoclay.In addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.
基金supported by National Natural Science Foundation of China (No.11075033)Mehler Engineered Products (Suzhou) Co. Ltd. of China
文摘Abstract A newly developed coaxial dielectric barrier discharge reactor with a length of 1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord in a roll-to-roll manner. In this reactor, swirling mixture gases of oxygen of about 1% and argon with a flow rate of 1.5 L/rain to 2.7 L/min ensured the gas usage sparing, discharge uniformity and efficient fiber surface modification. The water contact angle and surface morphology of the treated fiber were measured. The results show that the surface oxygenation is mainly responsible for the wettability improvement of the fiber cord when passing through the plasma zone at a linear speed of 3 m/min to 8 m/rain. The specimens of modified-polyester fiber reinforced rubber composite were also prepared for the interracial shear strength tests. Furthermore, the effect of adding oxygen into argon discharge on the fiber surface oxidation was correlated with optical emission spectroscopy. Finally, the effect of adding oxygen into argon discharge on the kinetic processes of the active species generation were also analyzed.
基金financially supported by the innovation project of science and technology plan of Shaanxi Province in 2015(No.2015KTCQ01-44)
文摘Improvement in synthetic fiber based composites is a hot topic in the material area.The incompatibility between the surfaces of synthetic fibers is a significant challenge due to fibers hydrophobic property.In this study,PET(polyethylene terephthalate) fibers based on low hydrophilic were slightly treated with NaOH or sodium dodecyl benzene sulfonate(SDBS).SEM images showed that there were some pits on the surface of PET fibers treated by NaOH,while PET fibers treated by SDBS became smoother.The peaks at 3725 cm^(-1) and 3628 cm^(-1) were generated for PET fibers treated by NaOH,which was attributed to—OH produced from the ester group hydrolysis,but no same peak is shown for the treated ones by SDBS.Meanwhile,the crystallinity indices of the treated PET fibers slightly decreased.Compared with original PET fibers,the formation of sheet made from PET fibers treated by NaOH became worse,but that from SDBS treated PET fibers became better.
文摘Modified polyester fibers were obtained using 2% and 6% of kaolin blends through melt spinning.The influences of two thermal treatments maintaining the original tension(180 ℃×2 min and 200 ℃×1 min)on the structure and properties of fiber were compared.The changes of grain size and crystallinity of fiber were investigated by X-ray diffraction(XRD).The changes of thermal properties of fibers were analyzed using dynamic mechanical analyzer(DMA).The results show that the crystalline structure of kaolin modified polyester fiber doesn't change with the thermal treatment.With the kaolin content increasing,the grain size of fiber changed.The higher the thermal treatment temperature is,the higher the crystallinity of fiber is.There are two glass-transition temperatures for kaolin modified:the lower one is the glass-transition temperature of polyester fiber matrix,and the higher one is derived from the heterogeneous blend of polyester matrix and nano kaolin.The higher the kaolin content is,the higher the glass-transition temperature is.Thermal treatment could increase the compatibility of polyester matrix and nano kaolin.There was only one glass-transition temperature for the thermal treatment fiber,and the heat resistance of fiber was improved.Thermogravimetric analysis-differential scanning calorimetry(TGA-DSC)results of kaolin modified polyethylene terephthalate(PET)matrix indicate that the decomposition temperature of PET fibers,kaolin modified PET fibers,and thermal treated fibers were little different within 40%-60% of weight loss rate range.
基金The Sustentation Fund of Science Technology Development of High University of Tianjin City's (021106)
文摘The degradation of diethylene glycol terephthalate (DTP) and polyethylene terephthalate (PET) fiber by microbe was studied.The degree of DTP degradation was determined by High Performance Liquid Chromatography (HPLC) to be more than 90%.The products after degradation of DTP and PET fiber were various.The degradation of DTP can be described by the first-order reaction model.The degradation of PET fiber was found to be little,but surface erosion of PET fiber could be clearly seen from the SEM photographs indicating there occurred some traces of biodegradation on the PET fiber surface.
文摘In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optical diagnostics.It is found that the interfacial adhesion strength between treated PET fiber and resorcinol formaldehyde latex(RFL)(little)-rubber was improved(about 50%) by the measurement of interfacial shear strength(IFSS) and peel test.The wettability was improved rapidly in the initial treatment time.It is considered that oxidation chemical reaction as the major role of PET fiber surface modification is ahead of the physical etching effect.The high density of atomic oxygen in the plasma by optical emission spectroscopy supports the purpose.According to the scanning electron micrograph(SEM) image in the work,the longer treatment time obviously caused physical etching effect,which shall be less responsible for the improvement of the wettability.
基金Supported by the National Natural Science Foundation of China(Nos.11475246 and 11175234)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA02030205)
文摘Reversible addition-fragmentation chain transfer(RAFT) mediated grafting of acrylonitrile onto Polyethylene/Poly(ethylene terephthalate)(PE/PET) composite fibers was performed using γ-irradiation as the initial source at ambient temperature. Different initial concentrations of 2-cyanoprop-2-yl dithiobenzonate were used as the chain transfer agent. The kinetics of graft polymerization is in accordance with the living RAFT polymerization. The successful grafting of acrylonitrile is proved by Fourier transform infrared spectroscopy analysis.The results of monofilament tensile test show that mechanical properties of the fibers change slightly after grafting. Scanning electronic microscopy images of the fibers show that the surface of RAFT grafted fibers is smoother than that of fibers grafted conventionally.
文摘Cation Dyeable Polyester(CDP)was made by copolymerizing dimethyl terephthalate(DMT),S-sodium sulfonate dimethyl isophthalate(SIPM) with a weight fraction of 4.5% and ethyleneglycol (EG).Blend of PET and CDP was spun into hollow fiber.The fiber was then treated withaqueous NaOH.In this paper,kinetics and mechanism of alkaline hydrolysis of PET,CDP andtheir blend PET/CDP fiber were studied by means of specific area measurement,scantling elec-tron microscopy and other chemical analyses.It was showed that the rate of alkaline hydrolysis isCDP】PET/CDP】PET.Because of blending effect,the alkaline hydrolysis of PET/CDP is dif-ferent from that of PET.CDP phase in the PET/CDP fiber is predominantly hydrolyzed,andhence some pieces of fiber(micro-fiber) fall off the fiber because of etching.
文摘为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。
文摘This paper deals with the fracture feature of three kinds of polyester fibers with differentstructures under different tensile conditions.We studied fracture initiation,crack propagationand ultimate fracture characteristics under tension of polyester fibers.The fracture features ofpolyester fibers are related with fiber structure and tensile condition.Crack is initiated in fibersurface.It propagates from outside to inside and eventually causes rupture of the fiber.In addi-tion,it is stated also that the analysis on tensile fracture feature of fibers might be confirmed bydynamic testing technique of scanning electron microscopy.
文摘Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester （PP/EHDPET） blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub>O solu-tion. We investigated the morphology of PP/EHDPETblend fibers before and after stretching and alkalinehydrolysis. Then thermal behavior of the blend has alsobeen studied.
文摘Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copolyester that can be rapidly hydro-degraded in the hot alkaline solution. This paper discussed the kinetics of alkaline hydrolysis of EHDPET, and the effect of catalyst, bulk ratio and the content of polypropylene grafted maleic anhydride (PP-g-MAH) on the alkaline hydrolysis process. Meanwhile, the morphological change of the outer surface of blend fibers during this process was also investigated by the technology of scanning electron microscope (SEM).
