摘要：
In order to investigate the influence of degumming on silk dissolution and fibroin properties, silk degummed by Na2CO3and urea was dissolved in CaCl2/CH3CH2OH/H2O ternary system, respectively. The degumming ratio, structure of degummed silk, dissolution process and rheological property,film-forming and microsphere properties of fibroin were tested by color spectroscopy, fourier transform infrared spectrometer, X-ray diffraction, gel electrogphoresis, scanning electron microscope. Results show that some fibroin will be dissolved in Na2CO3degumming,resulting in a higher degumming ratio,while the whiteness of silk degummed by Na2CO3is lower, compared with urea degumming. In addition,Na2CO3degumming has a great influence on the crystallinity of silk, and the heavy chain molecular unit of silk fibroin is damaged seriously in Na2CO3degumming, facilitating the penetration of Ca2+ion to fibroin to cause the degummed silk fiber easier to be dissolved. However, the molecular weight of silk fibroin is lower, and the structural viscosity of fibroin liquid is smaller, the mechanical properties and transmittance of silk fibroin membrane are reduced by Na2CO3degumming process, and the particle size of blank microspheres from Na2CO3degumming is smaller and the particle size distribution is more concentrated,compared with urea degumming.%为探究脱胶对蚕丝溶解及丝素蛋白的影响,分别将碳酸钠和尿素脱胶的蚕丝溶解在氯化钙/乙醇/水体系中,借助颜色光谱、红外光谱、X射线衍射、十二烷基硫酸钠 聚丙烯酰胺凝胶电泳、扫描电子显微镜等方法对蚕丝脱胶率、脱胶蚕丝结构、溶解进程以及丝素蛋白的流变、成膜及成球性能进行测试.结果表明:相对于尿素脱胶,碳酸钠脱胶可溶解部分丝素蛋白,脱胶率较高,脱胶蚕丝白度低;碳酸钠脱胶对蚕丝结晶度影响大,且对丝素蛋白重链分子单元破坏严重,有助于溶解体系中钙离子对丝素蛋白的渗透,使脱胶蚕丝较易溶解,但丝素蛋白分子量低,蛋白液黏度较小;碳酸钠脱胶降低了丝素蛋白膜的力学性能和透光率,制备的丝素蛋白空白微球粒径较小,分布较为集中.
