Natural silk fabrication

Silkworms and spiders have developed a set of complicated but efficient spinning systems. They can produce silks with different properties under mild, ambient conditions in an aqueous solution. Considering the supreme properties, they really employ an efficient procedure with minimum energy consumption. Only the conformation transitions happen and no active enzymes work in the solidifying process. As a result, there is a great deal of interest in understanding the precise details of how silk forms from silk proteins - whether in vivo or in artificial circumstances (Fahnestock and Steinbuchel, 2003 Vollrath and Knight, 2001). 

Besides the shear force and internal or external drawdown, that is, physical boundary conditions, the chemical environment for fiber formation, 

The combination of physical and chemical boundary conditions defines how the silk protein solution turns into a solid silk thread consisting of highly oriented molecules and hierarchically organized structures. 

These insights are forming the basis for advancing artificial spinning through mimicking of the natural process. 

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Mixed cotton, wool and natural silk fabric. 

If this shortened method is employed, the following rules must be followed in cotton and wool fabrics, the cotton is determined for preference as in case 1 (6) and the wool calculated by difference. In cotton and silk or wool and silk fabrics, the silk is determined for preference in the manner described in case 2 (c) and the other component calculated by difference. In cotton, wool and natural silk fabrics, the silk (2,c) and cotton (1,6) are determined for preference and the wool calculated. 

The feeling of a spider web may be unsettling, but a similar natural material has been used for centuries to make silk fabric that is prized for its smooth texture. Silkworms produce the silk fibers used to make clothing. They feast on mulberry leaves and convert the molecules from these leaves into silk, from which they spin cocoons. 

Silk. Silk, the only natural fiber that comes in filament form, has been and still is one of the most appreciated and valued textile fibers. Silk filaments are secreted by the larvae of several types of silk moths to make their cocoons. Most silk is derived, however, from the larvae of the Bombyx mori moth, which has been widely cultivated in China for over 5000 years. Fragments of silk fabric dated to the late fourth millennium b.c.e. were found at Qianshanyang, in the province of Zhejiang, in China. There are, however, even earlier indications of the use of silk silk remains were found together with an eleventh-century b.c.e. mummy in Egypt, probably also providing evidence of ancient trading routes between the Far and Middle East. 

Mixed fabrics containing natural silk and artificial silk based on either cellulose, or nitrocellulose or viscose. 

A. Mixed fabric containing cotton, wool, natural silk and artificial cellulose, nitrocellulose or viscose silk. 

Coated silk was not tested at 150 °C because Parylene-C undergoes a markedly increased degradation when heated above 135°C. Because initial observations on the discoloration of silk fabric indicated a change in the nature of the degradation reaction at temperatures above 110°C, calculations were performed both including and excluding the 150 C data. 

In view of the intricate structural features in natural silk, it becomes understandable that man-made silks in order to achieve satisfying mechanical properties will require a significant step-up in fabrication control to manage for example a proper degree of crystallinity and crystal size, as well as molecular chains organization and orientation. 

Accordingly, major hurdles will need to be overcome to achieve required performance including overcoming inherent weaknesses of natural silk such as super-contraction and fabrication consistency (Hakimi et al., 2007). To date, film, sponge-like silk, and nonwoven mat materials can artificially be made from silk solution, as mentioned in previous section (Vepari and Kaplan, 2007). 

A comparison of the state of degradation of historical silk fabrics with those of artificially aged contemporary fabrics would be very useful in any effort to determine the mechanisms by which naturally aged silk is degraded. Such knowledge would also aid in the selection and evaluation of stabilizers to slow the degradation process. For these reasons, the historical fabrics were evaluated. 

Figure 8 shows an Italian 17th century velvet fabric from a liturgical vestment of natural silk. 

Mordanted, Natural-Dyed Wool and Silk Fabrics... 

Materials. The wool fabric was a plain-weave worsted wool, style 6561, from Burlington Industries. The silk fabric was a degummed silk crepe, style 601, from Testfabrics, Inc. The dyes were >95% pure and were from the following sources alizarin (C. I. Mordant Red 8) from Aldrich Chemical Co. brazilin (C. I. Natural Red 24) from J. T. Baker Chemical Co. and carminic acid (C. I. Natural Red 4) from H. Kohnstamm Co., Inc. The five reagent grade metal salts used were aluminum potassium sulfate, stannous chloride, cupric sulfate, ferrous sulfate, and potassium dichromate from J. T. Baker Chemical Co. 

Blends of natural silk and polyester fibres (35 65) are sometimes used for dress goods, blouse fabrics and men s fashion wear. Sizing agents and soils are removed by washing with a minimum tension in open soaper containing 1 g/1 non-ionic detergent and 1 ml/1 NH3(25%) at 50 C. 

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