PHYSICOCHEMICAL PRINCIPLES OF SPINNING OF NATURAL FIBROIN FIBRES AND WAYS OF USING THEM IN CHEMICAL FIBRE TECHNOLOGY.Part 2.STRUCTURE AND PROPERTIES OF NATURAL FIBROIN FIBRES.USE OF PRINCIPLES OF BIOMIMETICS IN DEVELOPING CHEMICAL FIBRE TECHNOLOGIES

摘要

Natural silk fibres and cobweb silk fibres,like chemical fibres and filaments,have an amorphous-crystalline fibrillar structure[20-23,36,37]with a 50-60% degree of crystallinity(the lower figures are x-ray diffraction data and the higher figures are data from IR spectroscopy).The basic properties of natural silk filaments are as follows[15-19,22,23]:Density,g/cm3 1.32-1.36;Linear density,tex<0.5;Strength,cN/tex 25-35;Elongation at break,%18-25;Moisture content in standard conditions,% 10-13.The cross section of the fibres after spinning and boil-off is schematically shown in Fig.13.The generalized results of studies[38,39]of the properties of natural silk from silkworms of different species,which correspondingly consists of fibroin of different amino acid composition,are reported in Table 6.