Fabricating method for natural cellulose fiber blended with nano silver

A fabricating method for natural cellulose fiber blended with nano silver comprises following steps:

• (a) Put partially alkalized polyvinyl alcohol (PVA) power together with silver nitrate (AgNO3) solution as precursor thereof into pure water for agitating to form polyvinyl alcohol (PVA) solution in gel state such that the alkalization degree and the molecular weight of partially alkalized polyvinyl alcohol (PVA) power added is 86-89 mole % and 14,700-98,000 respectively while the weight percentage of polyvinyl alcohol (PVA) solution is 3-12 wt %, and the concentration of polyvinyl alcohol (PVA) solution is good enough to enclose and protect the micro silver particles formed therein because the polyvinyl alcohol (PVA) features in low polymerization degree and water-solubility at low temperature, and the silver nitrate (AgNO3) solution is created by dissolving the silver nitrate (AgNO3) crystal into pure water;
• (b) Put sodium borohydride (NaBH4) into the gel state polyvinyl alcohol (PVA) solution for reduction titration by agitating to form nano silver colloidal sol such that the reduction titration is performed by sodium borohydride (NaBH4) with mole ratio in range of 1:4-1:8, titration speed in range of 5-15 ml/min, agitating frequency about 200 rpm, and titration time about 10 minutes, and the concentration of produced nano silver sol is in range of 500-20,000 ppm while the diameter of the nano silver particle is in range of 10-150 nm;
• (c) Put the nano silver colloidal sol into a mixing cellulose serum of wood pulp raw material and N-methylmorpholine N-oxide (NMMO) solvent for blending process to prepare blending mucilage such that the blending process is performed by putting raw material of chipped wood pulp, solvent of N-methylmorpholine N-oxide (NMMO), and stabilizer together into an expansion dissolving tank with constant temperature in range of 60-80 degrees centigrade (° C.) for blending agitation, and in association of dehydration in a vacuum condensing equipment with vacuum about 933 micro-Pa. such that the content of α-cellulose is over 85% while the polymerization degree for the cellulose of wood pulp is in range of 500-1200, and the weight percentage for the nano silver sol in the prepared blending mucilage is in range of 5-35 wt % while the concentration of the nano silver particle therein is in range of 100-5000 ppm;
• (d) Evaporate water contained in the blending mucilage of nano silver colloidal sol and natural cellulose of wood pulp to form spinning dope by heating via a Thin Film Evaporator (TFE) under vacuum in range of 939-926 micro-Pa, heating temperature in range of 80-130 degrees centigrade (° C.) to dehydrate water down to range of 5-13% in 5 minutes so that the wood cellulose is dissolved into spinning dope with the composition percentages for all constituents in the spinning dope are as following:
• the percentage of water (H2O) is in range of 9-18%, the percentage of N-methylmorpholine N-oxide (NMMO) is in range of 75-87%, and the percentage of cellulose is in range of 6-11%;
• (e) Spin the spinning dope via “Dry-Jet Wet Spinning Method” by means of conveying the spinning dope via boosted pressure to a continuous polymer filter (CPF) for filtration and defoaming treatment, feeding the spinning dope into a spinning block for extruding out as melt trickle via spinnerets therein, and thinning the melt trickle into fibrous tow by stretching it through an air gap to form bundle of fibrous tow;
• (f) Feed the air cured fibrous tow into coagulation bath for coagulation, regeneration in coagulation liquid therein, and water rinse to form spinning filaments such that the concentration of the coagulation liquid is in range of 4.5-8.0%, and the residual quantity percentage of the N-methylmorpholine N-oxide (NMMO) solvent is less than 0.1% while the residual quantity percentage of the polyvinyl alcohol (PVA) solution is less than 0.3%;
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• (g) Treat the spinning filaments with dry, oil and coil in proper order to produce final product of natural cellulose fiber blended with nano silver.