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Maintaining a moist wound environment facilitates the wound healing process. However, traditional dressings such as medical gauze are difficult to meet this condition and easy to cause wound infection when the gauze is replaced. In this paper, a novel multifunctional medical dressing based on keratin porous materials was prepared by the freeze-drying method. Keratin was first modified by poly (ethylene glycol) dimethacrylate (PEGDMA) to increase its hydrophilicity. Then, the carboxymethyl chitosan (CMCS) was mixed with keratin solution to further improve the pore-forming properties, and finally, the solution was dried through the freezing method to obtain the porous dressing. The performance of the dressing was detailed and studied using DPPH free radical scavenging ability, water retention, blood coagulation, and bacteriostasis tests. The results showed that PEGDMA grafting greatly improved moisture retention from 22 to 43. CMCS blending not only improved the uniform and compact of the pore structure, but also effectively improved blood coagulation and antibacterial properties. After blending with CMCS, the performance of the keratin porous material was greatly improved. Carboxymethyl chitosan is positively charged, which makes the negatively charged platelets easy to aggregate, so the coagulation performance is greatly improved, and the BCI decreased to 15%. At the same time, the antibacterial performance against Staphylococcus aureus was greatly improved, and the optimal condition was PEG-g-KR:CMCS = 6:4. The PEG-g-KR/CMCS dressing prepared in this method had the characteristics of promoting wound healing, good moisture absorption and water retention, excellent blood coagulation performance and strong bacteriostasis. It is of great significance to the research and application of composite dressings. [ABSTRACT FROM AUTHOR]

As the most common synthetic fibre, polyester has consistently been in high demand and usage, but its recycling has always been a problem for the textile industry. The decolorisation of dyed polyester is the key to expanding its recycling use, and there is no rapid, effective and simple decolorisation method. In this study, ozone was used to decolorise dispersed dyes developed for polyester. Ozone was effective in decolorising CI Disperse Orange 30 and CI Disperse Blue 60, and the process was extended to the decolorisation of dyed polyester fabric. Based on single factor analysis, the optimum decolorisation technological conditions were: an ozone feed rate of 130 mg L−1 min−1, treatment time of 2 hours, wet pick‐up of 100% and pH value of 3, with which the decolorisation rate and colour difference values could exceed 45% and 6%, respectively. The changes in dye structure during the process of ozone decolorisation were analysed using scanning electron microscopy, X‐ray diffraction and Fourier Transform–infrared spectroscopy, and the mechanism of ozone decolorisation was also investigated. The results showed that the crystallinity decreased from 41.18% to 36.30% with a strength retention rate of above 80%, and demonstrated that ozone can be used on polyester fabric and dye simultaneously. The aim of entering the fibre was achieved by etching the polyester and decolorisation was achieved by oxidising the chromaticity groups. [ABSTRACT FROM AUTHOR]

The desizing efficiencies of starches are different. However, the reasons and mechanism for this appearance are still unclear. Therefore, desizing efficiencies of starches were measured, and the reasons for their difference were analyzed. Swelling ability and degree of crystallinity of starch films were tested to conform to the relation with desizing. The size residue on the desized yarns was collected to detect the difference in the proportion of nonstarch components and the structure of hydrolyzed starch. In addition, correlation analyses were conducted between the factors affecting hydrolysis and desizing efficiency. It was found that corn starch has the lowest desizing efficiency, and the efficiency of cassava starch was the highest. The largest proportion of protein was the main reason for inhibiting the desizing. Furthermore, a higher proportion of lipid and the lower swelling ability of starch film could also be an obstacle to desizing. Removing the nonstarch components and improving the swelling ability of film may be effective methods to improve the desizing efficiency of starch. [ABSTRACT FROM AUTHOR]