The invention discloses a preparation method of silk
protein fibers. The preparation method comprises the following steps of: (1) after peeling off cocoon shells into fragments, degumming a
sodium carbonate solution with the
mass percent of 3% for three times, and putting the fragments into a
vacuum drying box at the temperature of 75 DEG C and
drying; then dissolving dried silk
protein into a 1.5wt% NaOH solution; (2) carrying out
slicing treatment on tree raw materials, and boiling, finely selecting before bleaching, bleaching, finely selecting after bleaching, pulping, dehydrating and
drying to prepare pulp; (3) filling the pulp and liquid-state NMMO (Methylmorpholine-N-
Oxide) into a mixing kneading tank and heating the mixture at vacuum to 90 DEG C, so as to prepare a
spinning solution with the
cellulose concentration of 10%-25%; and (4) proportioning and commixing a silk
protein solution in the step (1) and the
spinning solution in the step (3), and adding a nano aromatic auxiliary agent and
spinning by adopting a dry-wet-method process. The silk protein fibers provided by the invention have soft luster and a smooth and soft hand feeling of real silk, and also keep good
moisture absorption and high
fiber strength of natural silk; and the silk protein fibers are more
skin-friendly and comfortable.