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In this study, a versatile method for the manufacturing of chitosan-grafted porous poly (L-lactic acid) (P-PLLA) nanofibrous membrane by using polydopamine (PDA) as an intermediate layer has been developed. P-PLLA fibreswere electrospun and collected as nano/micro fibrous membranes. Highly porous fibres could serve as a substrate for chitosan to adsorb heavy metal ions. Moreover, PDA was used to modify P-PLLA surface to increase the coatinguniformity and stability of chitosan. Due to the very high surface area of P-PLLA membranes and abundant amine groups of both PDA and chitosan, the fabricated membranes were utilized as adsorbent for removal of copper(Cu2+) ions from the wastewater. The adsorption capability of Cu2+ ions was examined with respect to the PDA polymerization times, pH, initial metal ion concentration and time. Finally, the equilibrium adsorption data of chitosan-grafted membranes fitted well with the Langmuir isotherm with the maximum adsorption capacity of 270.27 mg/g.

The present study relates to manufacturing, characterization and optimization of bagasse fiber reinforced composites. For this purpose, response surface methodology was applied to simultaneously optimize the tensile strength, tensile modulus and tensile strain of bagasse fiber reinforced composites. Three levels of process variables, including concentration of sodium hydroxide for bagasse fiber treatment (4, 6, and 8%), content of bagasse fiber (10, 20, and 30 wt%), and length of bagasse fiber (1, 2, and 3 inch) were used to design the experiments according to the Box–Behnken design. Experimental results were analyzed by analysis of variance and fitted to second order polynomial models by using multiple regression analysis. The Derringer’s desirability function revealed that the values of process variables leading to optimized tensile strength, tensile modulus and tensile strain are 4%, 14.2 wt% and 1 inch for concentration of NaOH for bagasse fiber treatment, content of bagasse fiber and length of bagasse fiber, respectively. Validation experiments were carried out and high degree of correlation was found between the actual values and the predicted values of tensile properties of bagasse fiber reinforced composites.

This article investigates how the bending stiffness of the core thread and the effect threads affect the average values and the variability of the structural properties of resultant fancy yarns. The Design of Experiment technique was used to study the effects of individual factors and the interactions of factors. The analysis indicated that that the bending stiffness of the effect thread was a main factor. Increases in the effect thread bending stiffness led to significant increases of the size of fancy profile and reductions of the number of fancy profiles. Additionally, there was a strong interaction effect between the bending stiffness of the core thread and the bending stiffness of the effect thread which influenced the structures of the resultant fancy yarns. It was also found that variations in the bending stiffness of the input threads were reflected in similar variations in the size and number of fancy profiles. The study is important for engineering the structure and the variation in structural properties of fancy yarns by selecting appropriate input threads.

In this research article, the PVDF (polyvinylidene fluoride)–PANI (polyaniline)–titanium nanotube (TNT) based nanocomposite membranes were synthesised through phase inversion method. The composition and structural properties of nanocomposite membranes were characterised by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscope (SEM). The significant properties of synthesised membranes such as distribution of pore size, thermal properties, mechanical properties, and photocatalytic behaviour of membranes were also studied. The hydrophilic properties of the composite membranes increased with filler content (PANI-TNT) and results in improved pure water flux (484.8 ± 2.9 L/m2 h−1) compared to that (312.0 ± 1.91 L/m2 h−1) of the pure PVDF membrane. The pure PVDF and nanocomposite membrane were further analysed in terms of their filtration properties such as adsorption of dyes (methyl orange, Allura red) and UV self-cleaning properties. The newly developed nanocomposite membranes showed excellent pollutant removal efficiency (~90%). The synthesised nanocomposite membranes also showed photocatalytic activities due to the presence of TNTs, and adsorption of methyl orange (MO) reduces significantly with the UV light irradiations. The UV self-cleaning property of the composite membrane was further confirmed due to their high flux recovery ratio of about 94%. The results show that embedded PANI-TNT within nanocomposite was photo-catalytically active and degrade the dye molecules from the surface of the nano composite membrane.

For nonwovens, fiber orientation distribution is an important structural characteristic that directly influences the anisotropic properties of the materials. Different Vslurry/Vbelt ratios were adopted to fabricate nonwovens during the wet-laid process. The results indicated that fiber orientation distribution of nonwovens can be regulated by adopting different Vslurry/Vbelt ratios owing to the web-forming principle of wet-laid techniques. Mechanical tests showed that both wet and dry tensile strength of nonwovens in different angle directions present anisotropy under different Vslurry/Vbelt ratio parameters. A liquid spreading distribution experiment proved that liquid spreading length and area of nonwovens could be manipulated using different Vslurry/Vbelt ratios in the fabrication process. Therefore, specific anisotropic properties of wet-laid hydroentangled nonwovens can be realized by controlling the process parameters for particular end-use applications.

Nanofibres with high surface area have various applications in many fields, such as filtration, tissue engineering and drug delivery. In the previous reported works, a lot of researchers have fabricated porous polymer nanofibres with porous surface structure, but few researchers could produce thoroughly hollow porous nanofibres by electrospinning. Here, we developed porous poly( l -lactide) (PLLA) fibres with good internal pore connection by two methods, i) removal of a pore-forming agent from PLLA composite fibres; ii) non-solvent induced re-crystallization of pure PLLA fibres. In the first method, electrospun PLLA/cellulose acetate butyrate (CAB) composite fibres were immersed into acetone to remove CAB. Results showed that the fibres with less CAB could produce porous structures. However, with the increasing of CAB content, the fibre surface had only a collapsed structure. In the second method, while pure PLLA fibres were immersed into acetone, the solvent-induced recrystallization of PLLA generated porous structures throughout the whole fibres. Owing to the higher crystallization, the mechanical properties of PLLA fibres were also highly improved.

In order to understand the impact of mechanical action on the wrinkling of cotton fabrics in a drum washer, fabric movement was observed and a movement index system was developed to characterize the textile motion. Results showed that wash load and spinning speed were the major factors influencing the smoothness of cotton fabrics, with a p value of 0.032 and 0.00 respectively at 95% confidence level. The analysis of fabric movement illustrated that when the wash load increased, the free motion region decreases and the ratio of passive motion region increase, resulting in severe wrinkling of cotton fabric.A regression model was developed to characterize the relationship between fabric movement and smoothness.. These findings help the understanding of the mechanism of wrinkling during a drum washer washing.

This study examines the relationships between the structure of fancy bouclé yarns and the bending stiffness of the input threads that are used to make those fancy yarns. Four fancy bouclé yarns and an extra two confirmation bouclé yarns were made to test the impact of the bending stiffness of the effect input threads. Six fancy yarns were made to test the impact of bending stiffness of the core thread on the fancy yarn structure. The structure of the fancy yarn was defined by the number of fancy profiles, the size of fancy profile, the circularity ratio of fancy profile and the shape factor of fancy yarn. It was found that increasing the value of the stiffness of the effect thread increased the size of fancy profile but decreased both the number of fancy profiles and the shape factor of fancy yarn. Those relationships were represented by regression models that were significant at α = 0.10. The deviation between the theoretical values and the real values was −14.39% and 2.07%. Further, up to a value of 8.636 g mm2, the bending stiffness of the core thread appeared not to have an effect on the structure of the fancy yarns. This study is important as it is the first that accounts statistically for the impact of bending stiffness of the input threads on the structure of the resultant fancy yarns. Therefore, it aids fancy yarn manufacturers when designing fancy yarns with predicted structures.

Purpose The purpose of this paper is to mathematically model the structure of doubled fancy yarns made by combining together several threads. Design/methodology/approach It was assumed that such a structure may have two distinctive parts – sinusoidal and helical (i.e. sigmoidal). This model is based on calculating the length of the effect thread in relation to the core thread. The case of having several variants of such a structure was discussed to account for several types of doubled fancy yarns. The number of wraps of the binder, the overfed ratio, and heights of the fancy profiles in the different parts were the fundamental parameters of this model. The effects of changes in the number of wraps, the overfeed ratio or both simultaneously, on this model, were also considered. The shape factor of fancy yarn was also modelled depending on the basic model of the structure. Findings The model was tested and the correlation coefficient between the theoretical value and the real value of length of the effect thread was 0.90. Originality/value This model is useful for predicting the length of the effect component based on the type, dimension and number of the fancy profiles of doubled fancy yarn, and for understanding the changes of the multiple-thread structure of fancy yarn when the overfeed ratio and/or the number of wraps were to change.

Polylactide (PLA) single polymer composites (SPCs) were prepared using PLA nonwovens made of core-sheath PLA fibers as raw materials by hot-pressing. The core and sheath materials were poly(l-lactide) (PLLA) and PLA with d-lactide of about 10 mol% (PLA90), respectively. The melt processing window of PLA SPCs reached more than 40 °C. The effects of hot-pressing temperature on the crystallinity, the size distribution of crystallites, the lamellar thickness and mechanical property of PLA SPCs were significant while those of hot-pressing pressure were small. The strong interfacial adhesion between matrix and reinforcement led to high mechanical properties of PLA SPCs. For pure PLA materials prepared at 180 °C, the tensile strength (σb), elongation at break (εb), the work of rupture (W) and impact strength (αcU) were only 19 MPa, 1.8%, 0.15 J, and 2.8 kJ/m2, respectively while those of the SPCs prepared at 130–160 °C were 47–65 MPa, 15–32%, 9–22 J, and 14.9–67.2 kJ/m2, respectively. With the increase of hot-pressing temperature, the σb, W and αcU decreased. Keywords: Polylactide, Core-sheath fibers, Single polymer composites, Melt-processing window

Two kinds of composite filter materials were prepared by regulating the structure of melt-electrospinning polypropylene (PP) webs. The self-designed multi-nozzle melt-electrospinning device was used to produce PP webs which deposited on PP spunbonded nonwoven. Firstly, the composite filter materials with different thickness and ratios of coarse/fine fibers were prepared, and the effect of the thickness and the ratio of coarse/fine fibers on filtration properties were studied. The results showed that the filtration efficiency and pressure drop increased as thickness increased. In addition, compared with the general filters which were composed of coarse or fine fibers, the filters with coarse/fine fibers had “low pressure drop” under the similar filtration efficiency. In the case of the ratio of coarse/fine fiber about 2:2, this filter achieved optimal performance. When the thickness was 0.42 mm, its filtration efficiency for particles more than or equal to 2.0 μm could reach more than 95 %. Its pressure drop and air permeability were 18.13 Pa and 54.69 mm/s, respectively, while those of general filter were 38.67 Pa and 10.02 mm/s, respectively. After that, the composite filter materials composed of various angles of oriented webs were produced. The results showed that the filtration efficiency for particles with the size of morethan or equal to 2.0 μm was higher than that of filters composed of one angle of oriented webs. In addition, the lower the orientation was, the lower the pressure drop was.

Cotton plain fabrics are prone to winkle and shrinkage during daily wear usage and care processes. In this research, cotton fabrics sample are subjected to pre-washing processes and an extended series of tumble-dry cycles using standard drying procedures to investigate the impact of the drying on appearance physical properties of cotton fabric including smoothness appearance (SA), dimensional shrinkage, bending stiffness. And Scanning electron microscopy (SEM), thermo-gravimetric analyzer (TGA) and x-ray diffraction (XRD) were also employed to investigate whether the repeated drying in dryer can cause changes in the thermal stability, the composition transform and microscopic damage of cotton fibers or not. Results showed that smoothness appearance grade of cotton fabrics significantly depended on drying cycles during first 15 drying cycles. The results of dimensional stability showed that the dimensional shrinkage of cotton fabric was slight and had no relationship with drying cycles. And found that the shrinkage of cotton fabrics in the warp direction (1.29-1.71%) is higher than that of cotton fabrics weft direction (0.002-0.045%). The bending stiffness of cotton fabric was enhanced by drum-drying based on the bending stiffness data. TGA curves and XRD analysis showed that drying had little effect on thermal stability and crystallinity of cotton fibers. This indicated that drying only affected the appearance physical properties of cotton fabric such as appearance smoothness, dimensional stability, did not change composition and molecular structure (crystallinity). And from multiple levels including fabric-level, yarn-level and fiber-level, explained reasons of fabric properties change (namely, damage behavior). Moreover, this finding is not only helpful to understand of damage mechanisms of cotton fabrics drying in domestic dryer, but also provided reference for dryer manufacturers to accurately specify the types of clothing that can be dried by using a dryer. Additionally, it is also helpful to guide consumers to correctly care clothing in textile daily care. For example, the drying in dryer was not suitable for 100% cotton shirt with higher requirement of smoothness appearance grade, but it was suitable for fabric that smoothness is not concerned in usage, such as 100% cotton quilts and jeans.

A series of monophenyl borate (MPB) modified high-ortho phenolic copolymer fibers (BOPFs) were prepared by melt-spinning of the high-ortho phenol-formaldehyde resins with different content of MPB, and cured in a formaldehyde solution. The solution curing fibers were heated up to 240 °C at elevated temperatures in N2. The effect of MPB on the structure and properties of the BOPFs was investigated by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA) and scanning electron microscope (SEM). The results show that a B-O linkage inserts into the high-ortho phenolic copolymer molecular chain with the addition of MPB, and increases the crosslinkage and thermal stability. The peak of O/P (ortho/para) value of fiber (1.94) and elongation (5.6 %) were obtained when BOPFs-4 was heat-cured at 240 °C for 2 h.

Wet-laid hydroentangled nonwovens are widely used for disposable products, but these products generally do not have good dispersibility and can block sewage systems after being discarded into toilets. In this study, both pulp fibers and Danufil fibers are selected as we hypothesize that the high wet strength and striated surface of Danufil fibers would allow us to produce nonwovens with better dispersibility while having enough mechanical properties. The wet strength and dispersibility of nonwovens are systematically studied by investigating the influence of the fiber blend ratio, fiber length, and water jet pressure. The results indicate that the percent dispersion could be as high as 81.3% when the wet strength is higher than 4.8 N, which has been improved greatly comparing the percent dispersion of 67.6% reported before.

Particulate matter (PM) poses a threat to people’s living environment. Fresh air ventilation systems can filter particulate matter and play an important role in enhancing indoor air quality. A high filtration efficiency material with low pressure drop prolongs the service life of the filters and reduces energy consumption. However, maintaining the long-term storage of charge in electret materials remains a challenge. Herein, we report a novel sheath/core bicomponent spunbond (BCS) electret material with low pressure drop and improved charge stability using polyethylene/polypropylene (PE/PP) as the matrix polymer and magnesium stearate (MgSt) as the charge enhancer. Benefiting from the three-dimensional (3D) fluffy structure created by the spunbond technique and through-air reinforcement, the resulting electret materials exhibit a low pressure drop of 37.92 Pa, excellent dust holding capacity of 10.87 g m–2, and high filtration efficiency of 98.94%. Moreover, due to the introduction of MgSt, the filtration efficiency only decreased by 4.1% in 90 days. The successful fabrication of PE/PP BCS materials with MgSt not only provided a promising medium for particle capture but also developed a new approach for the design of fresh air filtration materials.

Porous poly(L-lactic acid) (PLLA) nanofibrous membrane with the high surface area was developed by electrospinning and post acetone treatment and used as a substrate for deposition of chitosan. Chitosan was coated onto porous nanofibrous membrane via direct immersion coating method. The porous PLLA/chitosan structure provided chitosan a high surface framework to fully and effectively adsorb heavy metal ions from water and showed higher and faster ion adsorption. The composite membrane was used to eliminate copper ions from aqueous solutions. Chitosan acts as an adsorbent due to the presence of aminic and hydroxide groups which are operating sites for the capture of copper ions. The maximum adsorption capacity of copper ions reached 111.66 ± 3.22 mg/g at pH (7), interaction time (10 min) and temperature (25 °C). The adsorption kinetics of copper ions was established and was well agreed with the second-order model and Langmuir isotherm. Finally, the thermodynamic parameters were studied.

A paraffin microsphere-templated 3D porous EcoFlex sponge was prepared to selectively absorb oil or chemicals from water. The technology for producing this EcoFlex sponge does not need complicated synthesis processes or instruments, and the materials applied in this work are ecofriendly. Therefore, this sponge can be employed in the environmental field. EcoFlex sponges showed high hydrophobicity (contact angle = 140-143°) and oleophilicity. The developed sponge exhibits a porous three-dimensional framework inside with excellent internal connectivity, which contributes both better absorption capacity and faster absorption rate. For instance, the absorption capacity for chloroform can reach 3400 wt %. The absorption capacity of the sponge was optimized using different size of paraffin microspheres and these sponges exhibit relatively high absorption capacity in a short time (2 min). The volume of sponge expands in some oils and organic solvents: the increased volume capacity for hexane can reach 2200%. This sponge also has great recovery capability and durability; it keeps its original shape and absorption capacity after 15 cycles of oil absorption and compression.

Recycling carbon fibre is crucial in the reduction of waste from the increasing use of carbon fibre reinforced composites in industry. The reclaimed fibres, however, are usually short and discontinuous as opposed to the continuous virgin carbon fibre. In this work, short recycled carbon fibres (rCF) were mixed with flax and poly-lactic acid (PLA) fibres acting as the matrix to form nonwoven mats through wet-laying. The mats were compression moulded to produce composites with different ratios of rCF and flax fibre in the PLA matrix. Their flexural behaviour was examined through three-point-bending tests, and their morphological properties were characterised with scanning electron and optical microscopes. Experimental data showed that the flexural properties increased with higher rCF content, with the maximum being a flexural modulus of approximately 14 GPa and flexural strength of 203 MPa with a fibre volume fraction of 75% rCF and 25% flax fibre. The intimate mixing of the fibres contributed to a lesser reduction of flexural properties when increasing the flax fibre content.

This paper presents the performance of a new nonwoven piezo-resistive sensor for capturing cardiorespiratory signals. The novel piezo-resistive sensor is fabricated by sandwiching a nano silver electro-conductive ink impregnated nonwoven material between two layers of knitted silver fabric that function as sensor electrodes. The paper describes the technology for minimizing the signal noise due to motion artifacts in the sensor. The nonwoven piezo-resistive sensor is tested on volunteers by capturing their cardiorespiratory signals, where the signal noise is filtered using a bandpass filter. The paper further presents the analysis of the performance of the sensor together with a comparison against a commercially available, portable, cardiorespiratory signal monitoring device. The study shows that the wearable nonwoven piezo-resistive sensor system is highly sensitive, and it is an accurate and reliable sensor for capturing cardiorespiratory signals.

Electrospinning is a versatile method for making nanofibres from polymer solution. Hydroxypropyl-β-cyclodextrin (HP-β-CD) is electrospun from aqueous solution by blending with non-toxic, biocompatible, synthetic polymer poly(ethylene oxide) (PEO). The aqueous solutions containing 70:30 HP-β-CD/PEO polymer blend with 8 wt.% concentration were electrospun to study the effects of process parameters on fibre morphology. Electrospinning was carried out at variable feed rate, applied voltage and working distance to see the effects on process stability and fibre diameter. Scanning electron microscope images showed that increasing feed rate, applied voltage and working distance promote bead formation in the fibre. The average diameter of the nanofibres was measured using ImageJ software. It was observed that the fibre diameter increased with increasing the feed rate and applied voltage. In contrast, the diameter of the fibres decreased with increasing the working distance up to a certain level. Further increase o...

To fill the binary image of draped fabric into a comparable grayscale image with detailed shade information, the three-dimensional point cloud of draped fabric was obtained with a self-built three-dimensional scanning device. The three-dimensional point cloud of drape fabric is encapsulated into a triangular mesh, and the binary and grayscale images of draped fabric were rendered in virtual environments separately. A pix2pix convolutional neural network with the binary image of draped fabric as input and the grayscale image of draped fabric as output was constructed and trained. The relationship between the binary image and the grayscale image was established. The results show that the trained pix2pix neural network can fill unknown binary top view images of draped fabric to grayscale images. The average pixel cosine similarity between filling results and ground truth could reach 0.97.

Easy care for clothing is increasingly important, but the major problem is still the severe wrinkles formed on garments after machine washing. In this research, orthogonal tests and the analysis of variance (ANOVA) at a 95% confidence level were used to determine the critical parameters that affect fabric smoothness. We developed a video capturing and processing system for dynamic measurements of fabric in a top-loading washer to find the relationship between fabric movement and wrinkling performance during laundering. The ANOVA results showed that the smoothness of woven cotton fabrics was mainly affected by the washing load and the drum rotating speed, with p values of 0.000 and 0.036, respectively. Additionally, a relation models for fabric movements suggested by a curvilinear regression analysis indicated that the main causes of fabric wrinkling during top-loading washing were liquor ratio and the centrifugal force imposed on the fabric. The smoothness grade increased with the decrease of washing load and drum rotating speed, since these settings led to lower liquor ratio with a constant water volume and less stress on the fabric. The results of this study provide valuable information for the optimization of washing programs for fabric smoothness.

Despite the silk fabrics were widely used as luxury textile products, little information is available for dryer manufacturer setting drying parameters that consumers can use for silk production care. The purpose of this study is to determine the optimal drying procedure for large load and non-ironing procedure for small load when silk fabrics were used in daily life. Change in appearance, mechanical properties and microstructure of silk fabrics before and after drying were investigated. Drying experiments with various drying parameters (heater power, air flow rate and drum rotating speed) were performed on a self-modified domestic hot-air drum dryer. Experimental results reveal that the performance of silk fabric after drying is more sensitive to air flow rate (relative humidity of drying air) rather than heater power (temperature). The minimum drying damage is caused by lower heater power, absence of mechanical agitation and above moderate air flow rate. The total drying time is strongly dependent on heater power and air flow rate. Increasing these parameters shortens the drying time considerably. A drying procedure of heater power of 3000W, air flow rate of 8.5m/s and drum rotating speed of 45-50rpm (No.2) is proved to be optimal for drying silk fabrics due to its ideal smoothness appearance, dimensional stability and drying efficiency. When consumers dry a small amount of clothes, a drying procedure of heater power of 3000W, air flow rate of 8.5m/s and drum rotating speed of 0rpm (No.6) is more reasonable procedure because it reduces or eliminates ironing. And results shows that drum drying in dryer can be an effective alternative to indoor-drying or sunlight-drying if a suitable procedure is used. This finding can help the drying machine manufacturers to design and improve of dryers, especially for drying procedures optimization of delicate textiles. And it also provides consumers a feasible care method that does not reduce the quality of the dried silk fabric and the drying efficiency.

The aim of this research is to produce some three-dimensional (3D) nonwoven fabrics with variation in weight and type of fibre and then analyse their fibre orientation distribution by fast Fourier Transform (FFT) method. Three different fibres were used: polyester, polypropylene and blended polyester and polypropylene. Fabric weight varied from 20 to 180 g/m2. The processes of web formation and consolidation were based on the principle of air-laid and hot through-air thermal bonding technique. The result of the fibre orientation showed a random distribution of the fibres for all the samples. It indicated that there was no relationship between the variables and fibre orientation distribution. The position of 3D web whether from the top or side part did not show any variation and thus they did not have the influence towards the fibre orientation.

We have developed a mechanical hybrid yarn spinning system that produces different yam types on a modified open-end rotor spinning frame. In order to improve yam properties and produce novel yams, we investigate the effects of combinations with typical hybrid yams by inserting two filament yarns with varying filament over-feeds. The results are a new rotor spun loop (RSL) yam made by combining two aspects of typical hybrid yarn production into one process, and an RSL yam where a filament yam, fed with a core filament over-feed (CFOF), is located in the center of one yarn and the other filament yam, fed with the effect filament over-feed (EFOF), makes a loop on the yarn surface. The stable conditions of RSL yam production are within a range of EFOF ≧ 4 (m/min) and -6.0 << CFOF << -4.0 (m/min).

We have developed a mechanical hybrid yam spinning system that produces different kinds of yam on a modified open-end rotor spinning frame. In order to understand the characteristics of hybrid yam and produce novel yarns, it is necessary to investigate yarn formation and the twisting mechanism in the spinning rotor during yam production. Our results reveal that the rotor revolution generally results in combining the filament yam and the staple fiber strand. The fiber twist angle of the strand in a hybrid yarn is smaller than that of a rotor spun single yam with the same spinning conditions. Although a fed filament yam has a false twist inserted by increasing the filament over-feed, the filament yarn in the hybrid yarn has a smaller level of fiber twist angle in the same direction as the twist of the staple fiber strand due to untwisting of the false twist.

Highly porous polylactide (PLA) microfibers with the diameter of about 14 µm are prepared by melt-spinning and stretching core–sheath PLA fibers (CSF) and sequent treatment of ethyl acetate. The resultant pores are regular and elliptical. The average values of length of major axis and minor axis of elliptical pores are around 1 and 0.5 μm, respectively. This new and facile method can prepare porous PLA fibers on industrial scale, and nearly overcome all the shortcomings of melt-spinning and stretching method. In addition, highly porous structure in partially oriented poly(l-lactide) yarn (POY) can be also formed by treating POY using ethyl acetate. The obtained pores are irregular. In addition, the formation mechanism of pore structure in CSF is different with the one in POY. The former is the separation of row-nucleated lamellae induced by stretching while the latter is swelling and subsequent solvent-induced crystallization. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45860.