Alginate fiber and preparation method thereof

A preparation method for an alginate fiber, comprising:

• S10:
• mixing sodium alginate with a five-membered cyclic quaternary ammonium salt polymer in water to obtain a spinning solution, wherein a mass ratio of the sodium alginate to the five-membered cyclic quaternary ammonium salt polymer is 100:(0.001-30);
• S20:
• allowing the spinning solution obtained in S10 to stand for deaeration, and then extruding the spinning solution into a solidification bath at 40° C. to 70° C. to allow solidification molding to obtain a primary fiber,
• wherein the solidification bath comprises the five-membered cyclic quaternary ammonium salt polymer with a mass percentage concentration of 0.01% to 2%;
• S30:
• drawing and water-washing the primary fiber obtained in S20 to obtain an alginate fiber;
• and
• S40:
• soaking the alginate fiber obtained in S30 in a finishing agent at 20° C. to 70° C. for 5 min to 60 min,
• wherein the finishing agent comprises the five-membered cyclic quaternary ammonium salt polymer, and a mass of the five-membered cyclic quaternary ammonium salt polymer is 0.5% to 10% of a mass of the alginate fiber obtained in S30;
• and
• the five-membered cyclic quaternary ammonium salt polymer is
• wherein R1 is CH3 or CH2CH3 or CH2(CH2)4CH3 or CH2(CH2)10CH3 or CH2(CH2)16CH3 or C6H5CH2, R2 is CH3 or CH2CH3 or CH2(CH2)4CH3 or CH2(CH2) 10CH3 or CH2(CH2)16CH3 or C6H5CH2, and a degree of polymerization (DP) n ranges from 50 to 25,000.