Effect of blending ratio on the hollow coffee carbon polyester/cotton blended yarn

The effect of blending ratio on the performance of hollow coffee carbon polyester/cotton blended compact siro-spun yarn was investigated. Five blend ratios of hollow coffee carbon polyester/cotton fiber (i.e. 20/80, 35/65, 50/50, 65/35, and 80/20) and polyester/cotton fiber 35/65 were designed, and six groups of 14.6 tex yarn were spun by compact siro. Indices for the performance of the yarn (surface morphology, evenness, hairiness, tensile property, and hydroscopicity) were tested and analyzed. The regression analysis showed the excellent linear relationship between the content of hollow coffee carbon polyester and each performance index was obtained. Cubic curve models were built to comprehensively evaluate the performance of the yarn. The blending effect in these yarns was evaluated using the Hamilton transfer index. The tests results show that with the increase of the content of hollow coffee carbon polyester in the blended yarn, the evenness and tensile properties of the hollow coffee carbon polyester/cotton blended yarn continue to increase, whereas the hairiness index and moisture regain of the yarn gradually decrease. With the change of blending ratio, the transfer index of each fiber in hollow coffee carbon polyester/cotton blended yarn will change. When the content of hollow coffee carbon polyester is more than or equal to 50%, it has the tendency to preferentially distribute inward, whereas the cotton fiber has the tendency to preferentially distribute outward. When the content of hollow coffee carbon polyester is less than 50%, the reverse is true. The comprehensive evaluation value of the yarn performance decreased first and then increased with the increase in the content of hollow coffee carbon polyester.

Room-Temperature Hydrogen-Gas Sensor Based on Carbon Nanotube Yarn

The proposed study describes the development of a carbon nanotube (CNT)-based gas sensor capable of detecting the presence of hydrogen (H2) gas at room temperature. CNT yarn used in the proposed sensor was fabricated from synthesized CNT arrays. Subsequently, the yarn was treated by means of a simple one-step procedure, called acid treatment, to facilitate removal of impurities from the yarn surface and forming functional species. To verify the proposed sensor’s effectiveness with regard to detection of H2 gas at room temperature, acid-treated CNT and pure yarns were fabricated and tested under identical conditions. Corresponding results demonstrate that compared to the untreated CNT yarn, the acid-treated CNT yarn exhibits higher sensitivity to the presence of H2 gas at room temperature. Additionally, the acid-treated CNT yarn was observed to demonstrate excellent selectivity pertaining to H2 gas.

Synthesis of Corn Starch Derivatives and Their Application in Yarn Sizing

The use of synthesized natural starches for the sizing process in fabric production is primarily an environmental contribution. Synthesized corn starch is environmentally friendly and productive, showing good results in cotton yarn sizing. Acrylamide (AA) and 2-hydroxyethyl methacrylate (HEMA) were applied for the grafting process of corn starch, and the initiators azobisisobutyronitrile (AIBN), potassium persulfate (KPS), and benzoyl peroxide (BP) were chosen to form the grafted monomers more effectively. The application of synthesized corn starch has been confirmed, especially with the AIBIN initiator in the grafting process of HEMA onto starch. The FTIR analysis confirmed that new and efficient products for sizing cotton yarns based on natural raw material (corn) were developed. The research showed that the synthesized corn starch improved physical-mechanical yarn properties and abrasion resistance and reduced yarn surface hairiness. Ultrasonic desizing of yarn and the use of a lower size concentration led to better results than desizing by washing, and the Tegewa numbers confirmed that the desizing process was successful.

STUDI PENGHITUNG PACKING FRACTION MENGGUNAKAN FISIKA CITRA

Abstrak Packing fraction menunjukkan derajat susunan serat pada suatu benang, yang dihitung berdasarkan perbandingan antara volume serat terhadap volume benang atau lua serat total terhadap luas benang. Pada kondisi panjang serat dan panjang benang memiliki panjang yang sama, maka untuk menghitung volume serat maupun volume benang dapat didekati dengan penghitungan luas permukaan serat total dan luas permukaan benang. Penghitungan rasio luas permukaan serat terhadap luas permukaan benang yang akurat sangatlah sulit didapatkan dikarenakan bentuk permukaan serat yang sembarang dan perhitungan kalkulus matematika yang rumit. Untuk mengatasi masalah tersebut, maka diperlukan suatu metode fisika citra untuk menghitung luasan permukaan serat sembarang. Pada penelitian ini telah didapatkan suatu metode untuk mengukur nilai Packing fraction dengan lebih baik menggunakan metode pengolahan citra untuk mendapatkan luasan acak serat. Kata Kunci: packing fraction; benang; tekstil; image processing Abstract The Study Calculation of Packing fraction using physics of imaging. Packing fraction shows the degree of arrangement of fibers in a yarn, which is calculated based on the ratio between the volume of fiber to the volume of yarn or total fiber area to yarn area. In the condition of fiber length and yarn length have the same length, then to calculate volume of fiber and volume of yarn it can be approached by calculating the total fiber surface area and yarn surface area. Precise calculation of the fiber surface area to yarn surface area is very difficult to obtain due to the arbitrary shape of the fiber surface and complex mathematical calculation. To overcome this problem, we need an image processing method to calculate the surface area of any fiber. In this research, a method for measuring the value of Packing fraction has been better obtained using an image processing method to obtain a random area of ​​fiber. Keywords: packing fraction; yarn; textile; image processing

Numerical simulation of the effect of flow field in swirl nozzle spinning on yarn performance

Swirl nozzle spinning is an effective method to reduce ring-spun yarn hairiness due to device structure and vortex characteristics. This study establishes a computational domain of a swirl nozzle comprising an air inlet channel and a yarn channel to investigate the characteristics of the vortex in the swirl nozzle and the effects of inlet pressure on the wrapped force of the yarn. Simulation results show that the airflow rotates clockwise toward the two yarn entrance directions; moreover, the pressure at the central area of the yarn channel is lower than that of the surrounding area, which is good for the yarn’s steady movement and free fibers wrapping on the yarn surface into the yarn body. When the inlet pressure is high, the pressure spreading to each section of the yarn channel is also high. When the difference between the pressure near the inner wall and the yarn axis is high, the yarn surface has added high pressure, and the velocity and its fluctuation are also high. Experiment result reveals that 0.2 MPa is sufficient in significantly reducing yarn hairiness and that operating the nozzle under a low air pressure is economical. Thus, the numerical simulation can provide the theoretical as well as quantitative reference for the vortex tube design in the coming future.

A method to produce ring single yarn with fancy and anti-frictional structure by feeding filaments in front of the front roller nip

In this study, a composite ring spinning via feeding filaments in front of the front roller nip method was developed as a novel, effective way to form yarn surface looped fancy wrappings. The novel method was theoretically demonstrated to produce fil-wrap yarn with tight filament wrappings and periodic filament loop decorations on the surface. Tight filament wrappings fasten staple fibers firmly onto the yarn stem to achieve excellent anti-friction, while filament loops decorate the yarn surface to yield a fancy appearance. However, intensive bending of looped and wrapping filaments are likely sheared down to decrease the yarn’s tensile strength. The novel method was combined with corefil spinning to produce a fil-clamp yarn with enhanced structural fastness and strength. Experiments were conducted to validate the approach. Experimental results proved that the novel fil-wrap and fil-clamp yarns had periodic filament looped and tight wrappings, resulting in eliminated hairiness and increased fancy loops after comparison with conventional sirofil and corefil yarns. respectively. The fil-wrap yarn with only surface-bending filament wrappings was weaker, but more friction-resistant than conventional sirofil and corefil yarns. Yarn strength and anti-friction were enhanced after burying straight filaments in the fil-wrap yarn body to form a fil-clamp yarn. The fil-clamp yarn with fancy and anti-frictional structure is expected to endow fabrics with improved fluffiness, softness and anti-frictional properties.

Effects of Processing Parameters on the Mechanical Properties of Aramid Air Textured Yarns for Protective Clothing

This study examined the mechanical properties of a para-aramid filament according to the processing conditions of air-jet textured yarns (ATY). The specimens were prepared by changing the yarn speed, over feed ratio, air pressure, and heater temperature, which are important processing factors in the ATY process. The basic physical properties of the ATY, such as denier, tenacity, breaking strain, and initial modulus, were measured and their thermal shrinkage, such as dry and wet shrinkage, were measured to determine the thermal stability of the aramid ATY. In addition, the instability of para-aramid ATY were measured and assessed with the loop formation of ATY, according to the ATY process parameters. An examination of the effects of process parameters on the physical properties of aramid ATY revealed the core overfeed and air pressure to be the main factors. A high core overfeed and air pressure make the aramid ATY crimpy in the yarn core and entangle the fluffy loops on the yarn surface, resulting in an increase in the yarn linear density and breaking strain as well as a decrease in the tenacity and initial modulus. In contrast, these yarn physical properties were unaffected by the yarn speed, heater temperature, and wetting treatment. In addition, the dry and wet thermal shrinkage were unaffected by the process parameters of ATY. On the other hand, the instability decreased with increasing core overfeed and heater temperature and increased with increasing air pressure. These results showed that a high core overfeed makes the aramid ATY crimpy with an entangled yarn structure, and high air pressure helps provide small loops on the yarn surface. Finally, a high heater temperature makes the crimpy ATY structure more stable due to the strong heat set, which results in low instability.