Yu Ping Zhao

Extraction and Characterization of Silk Fibroin from Waste Silk

Waste silk fibers were dissolved in calcium chloride aqueous solution. Effect of calcium chloride concentration on silk solubility was studied. Dialysis method was used to purify the dissolved silk fibroin. The purified silk fibroin was characterized by FTIR and thermoanalysis technique. Results showed that the purified silk fibroin mainly had irregular curly conformation. The glass transition temperature of the regenerated silk fibroin reached 90.6°C-135°C, higher than 78.9°C-135°C before purification. Thermal weight loss temperature by 50% was 490.3°C differing from 429.7°C before purification.

The Dyeing Research of Wool Fibers Based on Reactive Disperse Dyes in Supercritical Carbon Dioxide

This paper adopts reactive disperse bright-red KR-2B to dye wool skeins in supercritical CO2 dyeing equipment. The influencing factors are analyzed by measuring the surface depth of dyed wool skeins, including time, temperature and pressure, and the optimal dyeing parameters are as following: time 60min, temperature 120°C, pressure 24 MPa. Then we adopt the scanning electron microscope (SEM) and the infrared spectrum (FTIR) to observe the apparent shape and structure before dyeing and after dyeing. The results indicate that the global dye structure divide and the dyestuffs have good fixation on the wool skeins.

Research on Bleaching Processes of Natural Cane Fiber by Ultrasonic

The effects of ultrasonic on bleaching of cane fiber were discussed in this paper. Ultrasonic frequency, ultrasonic time, the concentration of the hydrogen peroxide, temperature and pH value were optimized by the single factor experiment. The bleached fiber was analyzed by X-ray diffraction and Scanning electron microscope. The results showed the optimum processing parameters as follows: ultrasonic time 40 min, ultrasonic frequency 33 KHz (first 20 min); 55 KHz (second 20 min), temperature 90°C and the concentration of the hydrogen 30 ml/L, pH value 10.5. In the above conditions, the best bleaching effect was achieved.

Methods to Separate Polyester/Wool Blended Fabric

Polyester/wool blended fabrics were studied in this paper, and two methods were developed to separate polyester and wool fiber from physical and chemical respectively according to the characteristic differences between them. The characteristics and the ranges each method can be applied to were pointed out after analyzing factors like cost and conditions of production, complexity of the equipments, the length and continuity of the process and also the recovery of the product and pollutions. The study of this work not only decreased the waste of polyester/wool blended fabrics but also made full use of the two fibers. Also, the secondary pollution of polyester fiber was reduced and the value of wool can be reflected.

Influences of Coagulation Bath on Properties of Thermal Regulating PAN Fibers

Physical properties of thermal regulating polyacrylonitrile (PAN) fibers prepared at different concentration of coagulation bath were tested to investigate influences of coagulation bath on properties of the fibers. Results indicated that linear density of the fibers increased, breaking strength, thermal shrinkage and boil water shrinkage decreased while elongation first increased and then decreased with the increasing of mass fraction of sodium thiocyanate (NaSCN) in coagulation bath. The optimum NaSCN concentration in coagulation bath should be 10%. Fibers prepared under the above NaSCN concentration showed good mechanical and thermal properties, and the breaking strength was 1.35 cN/dtex, the enthalpy was 26.0 J/g and the thermal efficiency was 78.4%.

Mixed Reactive Disperse Dyes on Wool Yarn Dyeing in Supercritical CO2

Mixed reactive disperse dyes is adopted to dye wool yarn by supercritical CO2 dyeing equipment, and the influencing factors on the wool yarn uptake are analyzed including dyeing temperature, dyeing time, dyeing pressure. The results reveal the interaction relationship between single dyes dyeing on the wool yarn: the total uptake of mixed reactive disperse dyes and the uptake of single reactive disperse dyes increase with the increasing of temperature and pressure, it also increase by the extension of time. In the same conditions, the total uptake of mixed reactive disperse dyes is more than the uptake of single reactive disperse dyes. The uptake of single reactive disperse dyes in the mixed dyes is less than the uptake of single reactive disperse dyes. In the dyeing process of mixed dyes, the wool yarn dyeing of two dyes has selective and competitive. Both color fastness to rubbing and color fastness to washing of dyed wool yarn are in line with national institute of standards.

Linear Regression Analysis on Dyeing of Feather Fibers with Acid Dyes

Feather fibers dyed with the weak acid dyes in ultrasonic conditions. Influence of different dyeing time and dyeing temperature on dye uptake and the formaldehyde content was discussed through the multiple linear regression analysis method, respectively. This paper discussed the correlation between dye uptake, the formaldehyde content and dyeing time, dyeing temperature, and established linear regression equation of dye uptake, the formaldehyde content with different dyeing process conditions, respectively. The best dyeing time was 45min and the best dyeing temperature was 80°C, according to the linear regression equation. The experimental results showed that dye uptake could achieve 92.1% and the highest value of the formaldehyde content was 33.09 mg/kg. The linear regression of dye uptake and the formaldehyde content had a high fitting precision and a good predicting ability, which can be of guiding significance to the actual production.

Structure and Properties of the Anion Functional Alginate Fiber

An anion functional alginate fiber is developed by blended spinning, consisted by chitosan, nanometer tourmaline and other additives. Box-Benhnken Design response surface experimental design method is used to optimize the factors influencing anion emission, and the optimal anion releasing condition is as following: tourmaline 1.01g/100ml, coupling agent 0.23ml/100ml, dispersant 0.31g/100ml. By the optimal condition, the anion releasing quantity is 2950. Then FTIR, SEM, XRD are used to characterize the fiber, and the crystallinity is 0.78.

Study on the Supercritical CO2 Art of Dyeing

A new water-free dyeing process – Supercritical CO2 art of dyeing was proposed according to the high consumption of water and energy and serious environmental pollution problems. The results indicated that the effects of temperature, pressure and reaction time on dyeing deepness (K/S value) were investigated and the key factor is temperature. The PET fabrics dyed with disperse dyes in Supercritical CO2 were determined and the results showed that the dyeing protects with high dyeing rate and good characteristics, which can meet the requirements of the people on the dyed fabrics pattern and other visual art.

Application of Ultrasonic Wave in Dyeing of Feather Fibers

In this work, the dyeing methods with ultrasonic technology and tradition method were investigated. Dye uptake and rubbing fastness as detection index of feather fibers were analysed. The optimum conditions of dyeing in feather fibers with ultrasonic wave technology were determined: weak acid dye: dyeing temperature 70°C, time 40min; reactive dye: dyeing temperature 90°C, time 50min. The results showed that in this dyeing conditions, dye uptake using ultrasonic technology can reach 89.9%, that increased 31.9% comparing with that using traditional method; rubbing fastness can be over 3 grade, and the dry rubbing fastness was raised by 0.5~1 grade as compared with the wet rubbing fastness. It was found that the effect of dyed feather fibers can be better by using ultrasonic technology, which were eco friendly and so give good effect to human in addition to values on garments, and provided the beneficial to test for development of feather fibers.