Modified polyamide, method of preparing the same, and single component fiber

A method of preparing a spin drawn yarn single component fiber, comprising:

• copolymerizing C4-C12 lactam, C4-C18 linear aliphatic dicarboxylic acid, polyetherdiamine, and diethylenetriamine (DETA) to form a modified polyamide, wherein the lactam is 80 to 95 parts by weight, and the linear aliphatic dicarboxylic acid is 1 to 4 parts by weight, and the polyetherdiamine is 4 to 16 parts by weight, and the diethylenetriamine is 0.2 to 0.6 parts by weight, wherein copolymerizing the C4-C12 lactam, the C4-C18 linear aliphatic dicarboxylic acid, the polyetherdiamine, and the diethylenetriamine comprises a first copolymerizing process and a second copolymerizing process, the first copolymerizing process is performed at a temperature of 200° C. to 240° C. and a pressure of 1.2 bar to 3 bar, and the second copolymerizing process is performed at a temperature of 240° C. to 270° C. and a pressure of 0.1 bar to 0.5 bar;
• and
• performing a spinning process on the modified polyamide with a spinning speed of 2500 m/min, and a heating temperature between 260° C. and 280° C. to form the spin drawn yarn single component fiber.