Search Results (2)

As an important branch of ancient Chinese silk dyeing and printing technology, alkali degumming printing utilizes alkali agents to degum raw silk, creating differences in fiber water absorption, dye uptake, and optical characteristics between degummed and non-degummed areas to achieve localized pattern formation.Based on the differences in degumming processes of Silk Gauze using alkaline boiling, alkaline steaming, and alkaline gel, this study compares the effects of these three alkaline degumming techniques under different conditions of alkaline agent dosage, hot press temperature, and hot press duration. The degumming efficiency, fiber surface morphology, and infrared spectra of the degummed Silk Gauze were analyzed and compared. Through the analysis of the degumming mechanisms, it was found that the alkaline gel, within a localized micro-system, meets the conditions of alkali, water, and heat required for precise degumming of Silk Gauze. Combining the dual effects of alkaline boiling and alkaline steaming, the alkaline gel can achieve rapid degumming at a hot press temperature of 80 °C within 50 s, without significantly affecting the surface morphology or the primary structure of the Silk Gauze. The implementation of alkaline gel for precise degumming of Silk Gauze holds significant importance for expanding the application of traditional alkaline printing techniques in modern silk degumming and printing processes. Full article

Several studies have stated that the process used for sericin removal, or degumming, from silk cocoons has a strong impact in the silk fibroin integrity and consequently in their mechanical or biochemical properties after processing it into several biomaterials (e.g. fibers, films or scaffolds) but still, there is a lack of information of the impact on the features of silk nanoparticles. In this work, silk cocoons were degummed following four standard methods: autoclaving, short alkaline (Na₂CO₃) boiling, long alkaline (Na₂CO₃) boiling and ultrasounds. The resultant silk fibroin fibers were dissolved in the ionic liquid 1-ethyl-3-methylimidazolium acetate and used for nanoparticle synthesis by rapid desolvation in polar organic solvents. The relative efficiencies of the degumming processes and the integrity of the resulting fibroin fibers obtained were analyzed by mass loss, optical microscopy, thermogravimetric analysis, infrared spectroscopy and SDS-PAGE. Particle sizes and morphology were analyzed by Dynamic Light Scattering and Field Emission Scanning Electronic Microscopy. The results showed that the different treatments had a remarkable impact on the integrity of the silk fibroin chains, as confirmed by gel electrophoresis, which can be correlated with particle mean size and size distribution changes. The smallest nanoparticles (156 ± 3 nm) and the most negative Z potential (−30.2 ± 1.8 mV) were obtained with the combination of long treatment (2 h) of boiling in alkaline solution (Na₂CO₃ 0.02 eq/L). The study confirms that parameters of the process, such as composition of the solution and time of the degumming step, must be controlled in order to reach an optimum reproducibility of the nanoparticle production. Full article