Processing of Nylon-3 for Fiber Formation

NyIon-3 melts at about 340 C with considerable decomposition. Therefore, melt spinning cannot be used, but wet or dry spinning may be chosen for the fiber preparation. 

Nylon-3 is insoluble in most organic solvents and in water, as well as in aqueous basic solutions and dilute acid solutions. However, nylon-3 is soluble in water above 140-170°C, strong inorganic acids, organic acids, some aqueous and methanolic inorganic salts, hot aqueous phenol, and aqueous chloral hydrate. As for inorganic salts, Ca(SCN)2, LiCl, CaBrj, 

Wet spinning of nylon-3 is only possible when the spinning dope uses formic acid solution. Masamoto et al. [17] studied various solvents, and they established these conclusions. The available reduced viscosity of the polymer was from 0. 9 to 3. 0, and the preferable polymer concentration is from 38 to 40 wt%. In wet spinning, the combination of the solvent and coagulant is important. The coagulants which exhibit fiber forming abilities are as follows  

Organic solvents such as propanol, i-propanol, butanol, hexanol, diisopropylether, dioxane, tetrahydroftiran, methyl acetate, ethyl acetate, i-propyl acetate, butyl acetate. Water and water containing formic acid were not useful coagulants. 

Swelling (%) (Weight of protofibers)/Weight of polymer in protofibers) x 100 

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