鲜茧与干茧生丝的结构与性能比较及其鉴别方法

为有效鉴别鲜茧生丝和干茧生丝,借助电子显微镜、傅里叶红外光谱、X射线衍射仪、热重分析仪和表面接触角测试等分析手段对鲜茧生丝和干茧生丝的表面形貌和结构、性能进行表征和分析,并基于它们结构与性能的差异建立了较为准确和简单易行的生丝鉴别方法。结果表明:2种生丝的化学组成相似,其大分子二级构象均主要为β折叠构象,且热分解曲线也基本一致;但与干茧生丝相比,鲜茧生丝的表面较为粗糙,茧丝之间空隙较大,结晶度略低且亲水性好。使用测定生丝束在十二烷基苯磺酸钠水溶液中沉降时间的方法能够有效地鉴别2种生丝,其中鉴别鲜茧生丝的准确率达到100%,而鉴别干茧生丝的准确率接近80%。

Comparison between structure and performance of fresh cocoon raw silk and dry cocoon raw silk and identification method thereof

In order to identify fresh cocoon raw silk and dry cocoon raw silk, the surface morphology and structure properties of the two kinds of raw silk were characterized and compared by using electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermal gravimetric analysis and contact angle test, respectively, and then on the basis of the difference between their surface properties, an relatively simple and accuracy identification method for the two kinds of raw silk was established. The results indicated that the two kind of raw silk have the similar chemical composition, p-sheet conformation and thermal decomposition curves. However, compared with dry cocoon raw silk, fresh cocoon raw silk has a more uneven surface and a bigger gap between single fibers. Additionally, it showed less crystallinity and better hydrophilicity than dry cocoon raw silk. The two kinds of raw silk were efficiently identified using a method based on determination of their settling times in sodium dodecyl benzene sulfonate aqueous solution. The accurate rates of this method are as high as 100% for fresh cocoon raw silk and near 80% for dry cocoon raw silk, respectively.