Hong Cui

Research into kapok yarn can fully harness the unique functional advantages of kapok, such as its light weight, high thermal insulation, water-repellent and breathable properties, and biodegradability. In order to solve the problems of difficult yarn formation of kapok fiber, limited twist reduction of ring-spun weak-twisted yarns, and low production efficiency of traditional ring spinning, this paper proposes a false core spinning principle, with the main body fiber kapok/cotton 20/80, and the false-core yarn is made of 5.8 tex Vinylon staple fiber. 29.2tex yarns with different twist factors (350, 300, 250, 200, 150, 100) were spun to find out the lowest twist factor of 100, and yarns of different densities (19.4 tex, 14.6 tex, 11.7 tex, 9.7 tex, 8.3 tex, 7.3 tex, 6.5 tex, 5.8 tex) were spun to find out the lowest linear density of 5.8 tex with the lowest twist factor of 100.The spun yarns were woven into plain fabrics as weft yarns, and the softness of the fabrics gradually increased with the reduction of the twist factor ; the breathability gradually increased. The softness of the fabric gradually increased with the reduction of yarn density ; the air permeability of the fabric first decreased and then increased. Compared with ordinary ring-spun yarn, the false-core ultra-low-twist super-soft yarn achieves a maximum production-efficiency improvement of 124.97%.

This study investigates the influence of spinning process parameters on microfiber release from polyester fabrics, identifying yarn hairiness as the dominant controlling factor. Experimental results demonstrate an extremely high correlation ( R ² = 0.997) between 3 mm hairiness and microfiber release, confirming protruding fibers as the primary shedding source. Among the parameters examined, spinning method exhibits greater influence than twist factor, with Siro compact spinning consistently delivering optimal performance by achieving minimal hairiness and microfiber release while maintaining high breaking strength. The optimal combination was determined as Siro compact spinning with a twist factor of 400. The research establishes that spinning method's effect on microfiber release is primarily indirect, mediated through its determination of yarn hairiness. These findings provide a scientific basis for source reduction of microplastic pollution in textiles, demonstrating that proper selection of spinning technologies and process parameters can significantly reduce microfiber shedding at the manufacturing stage. The study offers practical solutions for developing more sustainable textiles and advancing green manufacturing practices in the textile industry, contributing to environmental protection and circular economy objectives.

Microplastics refer to plastic fibers, particles or films less than 5 mm in diameter. Textile microplastics are an important form of microplastics, which can harm the ecological environment and human health. This paper studies the relationship between textile microplastic shedding and fabric structure to reduce microplastics pollution and reduce its impact on humans and the natural environment. Firstly, household washing is simulated by considering the main fabric type, the number of steel balls used in the washing, washing temperature, washing time and other influencing factors. An orthogonal test of the mixing level of the four factors is designed by selecting the fabric type, the number of steel balls used in washing, washing temperature and washing time, and the influencing factors is analyzed, and the best washing scheme is obtained. Then, under optimal washing conditions, the three factors and three levels of orthogonal test are designed to analyze the influence of fabric structure and external factors on the shedding of microplastics by changing the amounts of friction and insolation time. The results show that the microplastics released by knitted fabrics are significantly more under the same washing conditions than that of woven fabrics. Satin fabrics released the most microplastics and plain fabrics the least. In addition, among the external factors, the amount of friction significantly affects the production of microplastics.

Polyimide yarn as a kind of high performance fiber material has to improve the adhesion between the material surface and the resin in order to get a deeper application. The surface of polyimide yarn is modified by low temperature plasma treatment, and the effect of plasma treatment parameters on the adhesion between polyimide yarn and polypropylene resin is studied. By comparing the extraction force on the surface of polyimide yarn before and after treatment, the effect of plasma treatment parameters such as treatment time, processing gas and treating power on yarn adhesion is investigated. Furthermore, the adhesive force between polyimide yarn and polypropylene resin is analyzed by a single factor to optimize the process parameters to obtain higher adhesive force. Additionally, the Box–Behnken design is utilized to optimize the plasma treatment parameters, and the significance of the influence of the plasma treatment parameters on the adhesion between the polyimide fiber and the resin is discussed. The optimal process parameters are obtained through analysis: the treatment time 90 s, the processing gas oxygen, and the treating power 150 W.

The mulberry fiber is extracted from the mulberry bast by biochemical degumming method. Based on the single factor experiment, the orthogonal experiment is further designed. The optimal process parameters for biochemical combined degumming are as follows: pretreatment stage, sulfuric acid solution concentration 2.5g/L, time 1h, temperature 60°C, bath ratio 1:20; alkaline pectinase treatment stage, alkaline pectinase solution concentration 46g/L, time 8h, temperature 50°C, bath ratio 1:20, solution pH = 9; alkali boiling stage, sodium hydroxide solution concentration 10g/L, alkali boiling time 3h, sodium silicate 30g/L, temperature 100°C, bath ratio 1:20; xylanase treatment stage, the concentration of xylanase solution 9g/L, the time 4h, the temperature 50°C, the bath ratio 1:20, and the solution pH = 4.8. By comparing the properties of mulberry fiber obtained by biochemical degumming and chemical degumming, it is found that the biochemical degumming process has less damage to fibers and more effective removal of lignin and hemicellulose.

Mulberry fiber is a new natural fiber. More and more attentions are paid to mulberry because of its good properties. The traditional chemical degumming method is liable to cause environmental pollution. This subject adopts the method of biochemical degumming technology to obtain mulberry fibers with certain spinnable properties. The degumming process of mulberry bark is studied on the basis of knowing the chemical composition and percentage content of the material composition of the raw material of mulberry bark, and the influence of different process conditions and parameters on the degumming effect is analyzed. Through single factor experiment and analysis of results, the optimized process parameters of biochemical combined degumming are as follows: the temperature and concentration of pickling acid pretreatment are 60°C and 2.5 g/L, respectively. The concentration, duration of action, and bath ratio of alkaline pectinase are 47 g/L, 8 h, and 1:20, respectively. The concentration and action time of sodium hydroxide in alkali boiling are: 10 g/L, 3 h. The concentration, duration of action, and bath ratio of xylanase are 10 g/L, 4 h, 1:20, respectively. The optimization process parameters obtained above lay the foundation for further orthogonal experiments to obtain the optimal degumming process.

In order to obtain the optimal collocation of two important technological parameters in the spinning process, the multi-response surface method was used to optimise the experimental results. Through the orthogonal design of the two factors and four levels of factor encoding, 16 groups of orthogonal experiments were designed; the experimental results were fit using the curve fitting toolbox of Matlab; a regression equation of yarn quality indicators, and in addition to a three-dimensional surface chart, an optimal scheme of the roving twist factor and spinning drafting for a roving twist factor of 110 were established; a spinning back draft of 1.5 was obtained based on experimental results of the response surface analysis and variance regression analysis. Experiments on the optimal scheme were carried out to verify the practicability of the results obtained by this method. The results show that application of the multiple response surface method to the optimisation of process parameters is of practical significance. This method can be applied for the optimisation of other process parameters.

A mathematical model is established for self-twist spinning process by applying laws of fluid mechanics (i.e. mass conservation and momentum conservation). The motion curve of the convergent point was determined and the convergence point was decided by densities and velocities of two fed-in strands and the resultant self-twist yarn, independent of their mechanical properties. The experimental verification proves that the motion trajectory of the convergence point reaches a better agreement with the theoretical trajectory. The results provide general way to study the self-twist yarn spinning process and optimize the process parameters.