The wettability of the solid surface is often characterized by the contact angle of the liquid on the solid surface. However, it has long been found that the contact angle of liquid on a solid surface can take a range...The wettability of the solid surface is often characterized by the contact angle of the liquid on the solid surface. However, it has long been found that the contact angle of liquid on a solid surface can take a range of values between two extremes： the advancing and the receding contact angles. The difference between the advancing and the receding contact angles is conventionally called contact angle hysteresis. Knowledge of contact angle hysteresis is essential to understand surface wettability and control surface wetting behavior. The wettability can be affected, for example, by the roughness of the solid surface. In our work, textile is used as macroscopic roughness surfaces, and smooth plate surface is used as well to determine contact angle hysteresis. The advancing and receding contact angles are measured on polyamide materials.展开更多
This study demonstrated that the changes in functional properties of both woven and knit cotton fabrics were determined to evaluate the performance of different special finishes. Here, 100% cotton fabrics were treated...This study demonstrated that the changes in functional properties of both woven and knit cotton fabrics were determined to evaluate the performance of different special finishes. Here, 100% cotton fabrics were treated with different types of finishing chemicals at different formulations. To assess the performance of different finishes on fabric properties, GSM, bursting strength, tensile strength, dimensional stability, absorbency, crease recovery angle with ASTM and AATCC methods were done. The results showed that the functional properties of the finished cotton fabrics both woven and knit depend to a great extent on the type of finish.展开更多
Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential bi...Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential biomedical biocompatible products in different forms from alginate fibres. Alginate nanofibres were prepared from sodium alginate polymer with the presence of poly-(ethylene oxide) (PEO), a small amount of Triton ×100 surfactant. A homogeneous spinning solution was prepared for producing Na-alginate/PEO nanofibers in electrospinning device. Nanofibres were produced by electrospinning from 70:30 and 80:20 Na-alginate/PEO of 4% solution. After a series of trials, the electrospinning parameters were optimized at 16 cm working distance, 0.4 mL/h flow rate and 10.5 kV applied voltage. The results show that the 4 wt% of 70:30 Na-alginate/PEO solution with 0.5 wt% Triton × 100 surfactant yielded smooth and stable electrospinning. The surface morphology of the fibres was investigated using Scanning Electron Microscope (SEM) and found the uniform fibres with an average diameter of 124 nm containing few thick or spindle-like fibres. FTIR investigation identified the chemical structure and molecular changes that occurred in the fibers.展开更多
Silk fabric-based wearable electronics stand among the most effective materials for the electronic skin function,due to their flexibility,robust mechanical features,and bio-compatibility.However,the development of fab...Silk fabric-based wearable electronics stand among the most effective materials for the electronic skin function,due to their flexibility,robust mechanical features,and bio-compatibility.However,the development of fabric sensors is restricted by limited resilience and the weak binding force of conductive materials to fabrics.Herein,a general strategy is developed for designing SF wearable devices with high elasticity and conductivity,combining the macroscopic design of three-dimensional SF structure,microscopic plasma-activated β-FeOOH scaffolds and in situ polymerized polypyrrole.Significantly,the fabric exhibits a maximum tensile strain of up to 30%,high conductivity(resistivity of 0.3Ω·cm),fast response in sensing(50 ms),and excellent durability(>1500 cycles).The possible mechanism of plasma activation of akaganeite scaffolds to produce zero-valent iron and induce pyrrole polymerization is analyzed.In addition,the e-textiles are demonstrated for personal-care management,including motion recognition,information interaction and electric heating.This work provides a novel guide to constructing advanced fabric-sensor devices capable of high conductivity and elasticity,which are expected to be applied in the fields of health monitoring,smart homes,and virtual reality interaction.展开更多
Manufacturing of a macro-scale helix auxetic yarn(HAY)was described. Consequently areal woven fabric and three kinds of woven fabrics various in weaves were introduced respectively. Their expected auxetic effect( assu...Manufacturing of a macro-scale helix auxetic yarn(HAY)was described. Consequently areal woven fabric and three kinds of woven fabrics various in weaves were introduced respectively. Their expected auxetic effect( assured by double helix yarn) was tested through the Poisson's ratio value(for auxetic structure is negative).Other observed parameters talked about variation in woven fabric porosity and the pores' parameters during the sample straining.Setting of this non-standard test( connection between dynamometer and image analysis) was also introduced. The differences among observed parameters were evaluated and conclusions for three types of woven fabrics were determined. It was found that less auxetic behavior caused less porosity. Less auxetic structure( satin) with longer floating threads embodies bigger pores' size and less circularity. The plain pattern has the greatest porosity but the smallest pores; the satin pattern behaves by contraries.展开更多
A stochastic approach based on a 3D 3-state Potts model combined with Monte Carlo simulation was used to study the equilibrium wicking height of liquids in vertical cylindrical capillaries. The Lifshitz-van der Waals ...A stochastic approach based on a 3D 3-state Potts model combined with Monte Carlo simulation was used to study the equilibrium wicking height of liquids in vertical cylindrical capillaries. The Lifshitz-van der Waals and Lewis acid-base theories were adopted to characterize the apolar and polar interactions in the spin system. The evolution of the spin system was driven by the difference in total energy for two successive states. To verify the model, equilibrium wicking height of water, formamide, heptane, and octane in capillaries of different radii were examined and the corresponding computer simulations were implemented. Good agreement was obtained between the simulation and experimental results. It shows the potential of the proposed approach to be applied in this area.展开更多
Ccanposites are common material constructions for high-tech use now. Mechanical properties of woven reinforced composites are influenced by voids inside the structure. Voids could be classified to the two sections. Lo...Ccanposites are common material constructions for high-tech use now. Mechanical properties of woven reinforced composites are influenced by voids inside the structure. Voids could be classified to the two sections. Long and thin cracks are more dangerous than pores. It is important to find relations between preparation and place of occurrence of voids. This paper classifies defects according to rise mechanism, point of occurrence, orientation, size and affect to the properties. Image analysis was used for observing samples. Future work would be oriented not only to observing real samples, bet also to calculate mechanical properties frwn real and ideal structures in 3D woven reinforced composites.展开更多
文摘The wettability of the solid surface is often characterized by the contact angle of the liquid on the solid surface. However, it has long been found that the contact angle of liquid on a solid surface can take a range of values between two extremes： the advancing and the receding contact angles. The difference between the advancing and the receding contact angles is conventionally called contact angle hysteresis. Knowledge of contact angle hysteresis is essential to understand surface wettability and control surface wetting behavior. The wettability can be affected, for example, by the roughness of the solid surface. In our work, textile is used as macroscopic roughness surfaces, and smooth plate surface is used as well to determine contact angle hysteresis. The advancing and receding contact angles are measured on polyamide materials.
文摘This study demonstrated that the changes in functional properties of both woven and knit cotton fabrics were determined to evaluate the performance of different special finishes. Here, 100% cotton fabrics were treated with different types of finishing chemicals at different formulations. To assess the performance of different finishes on fabric properties, GSM, bursting strength, tensile strength, dimensional stability, absorbency, crease recovery angle with ASTM and AATCC methods were done. The results showed that the functional properties of the finished cotton fabrics both woven and knit depend to a great extent on the type of finish.
文摘Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential biomedical biocompatible products in different forms from alginate fibres. Alginate nanofibres were prepared from sodium alginate polymer with the presence of poly-(ethylene oxide) (PEO), a small amount of Triton ×100 surfactant. A homogeneous spinning solution was prepared for producing Na-alginate/PEO nanofibers in electrospinning device. Nanofibres were produced by electrospinning from 70:30 and 80:20 Na-alginate/PEO of 4% solution. After a series of trials, the electrospinning parameters were optimized at 16 cm working distance, 0.4 mL/h flow rate and 10.5 kV applied voltage. The results show that the 4 wt% of 70:30 Na-alginate/PEO solution with 0.5 wt% Triton × 100 surfactant yielded smooth and stable electrospinning. The surface morphology of the fibres was investigated using Scanning Electron Microscope (SEM) and found the uniform fibres with an average diameter of 124 nm containing few thick or spindle-like fibres. FTIR investigation identified the chemical structure and molecular changes that occurred in the fibers.
基金supported by the Public Welfare Project of Zhejiang Province(LGF21E030005)National Natural Science Foundation of China(NSFC 51803185)the China Scholarships Council for supporting research at National University of Singapore(202008330177).
文摘Silk fabric-based wearable electronics stand among the most effective materials for the electronic skin function,due to their flexibility,robust mechanical features,and bio-compatibility.However,the development of fabric sensors is restricted by limited resilience and the weak binding force of conductive materials to fabrics.Herein,a general strategy is developed for designing SF wearable devices with high elasticity and conductivity,combining the macroscopic design of three-dimensional SF structure,microscopic plasma-activated β-FeOOH scaffolds and in situ polymerized polypyrrole.Significantly,the fabric exhibits a maximum tensile strain of up to 30%,high conductivity(resistivity of 0.3Ω·cm),fast response in sensing(50 ms),and excellent durability(>1500 cycles).The possible mechanism of plasma activation of akaganeite scaffolds to produce zero-valent iron and induce pyrrole polymerization is analyzed.In addition,the e-textiles are demonstrated for personal-care management,including motion recognition,information interaction and electric heating.This work provides a novel guide to constructing advanced fabric-sensor devices capable of high conductivity and elasticity,which are expected to be applied in the fields of health monitoring,smart homes,and virtual reality interaction.
文摘Manufacturing of a macro-scale helix auxetic yarn(HAY)was described. Consequently areal woven fabric and three kinds of woven fabrics various in weaves were introduced respectively. Their expected auxetic effect( assured by double helix yarn) was tested through the Poisson's ratio value(for auxetic structure is negative).Other observed parameters talked about variation in woven fabric porosity and the pores' parameters during the sample straining.Setting of this non-standard test( connection between dynamometer and image analysis) was also introduced. The differences among observed parameters were evaluated and conclusions for three types of woven fabrics were determined. It was found that less auxetic behavior caused less porosity. Less auxetic structure( satin) with longer floating threads embodies bigger pores' size and less circularity. The plain pattern has the greatest porosity but the smallest pores; the satin pattern behaves by contraries.
基金Science Foundation of Zhejiang Sci-Tech University(ZSTU),China(No.0901804-Y)
文摘A stochastic approach based on a 3D 3-state Potts model combined with Monte Carlo simulation was used to study the equilibrium wicking height of liquids in vertical cylindrical capillaries. The Lifshitz-van der Waals and Lewis acid-base theories were adopted to characterize the apolar and polar interactions in the spin system. The evolution of the spin system was driven by the difference in total energy for two successive states. To verify the model, equilibrium wicking height of water, formamide, heptane, and octane in capillaries of different radii were examined and the corresponding computer simulations were implemented. Good agreement was obtained between the simulation and experimental results. It shows the potential of the proposed approach to be applied in this area.
基金Supported by the Czech Scientific Foundation (No.106/03/ H150)
文摘Ccanposites are common material constructions for high-tech use now. Mechanical properties of woven reinforced composites are influenced by voids inside the structure. Voids could be classified to the two sections. Long and thin cracks are more dangerous than pores. It is important to find relations between preparation and place of occurrence of voids. This paper classifies defects according to rise mechanism, point of occurrence, orientation, size and affect to the properties. Image analysis was used for observing samples. Future work would be oriented not only to observing real samples, bet also to calculate mechanical properties frwn real and ideal structures in 3D woven reinforced composites.
