Fully degradable non-woven fabric produced by melt-blow extrusion and application thereof in production of medical masks

A fully degradable non-woven fabric produced by melt-blown extrusion, wherein the fully degradable non-woven fabric is prepared through steps:

• (S1) adding lactic acid (L-LA) and ε-caprolactone (ε-CL) into a reaction vessel to obtain a reaction system, wherein a weight ratio of the lactic acid (L-LA) to the ε-caprolactone (ε-CL) in the reaction system is 1:(2-4);
• adding a catalyst to the reaction system followed by reaction at 130-140° C. under vacuum for 18-24 hours to obtain a crude copolymerization product;
• wherein the catalyst is 0.1-0.2% of a total weight of the reaction system;
• and
• purifying the crude copolymerization product to obtain a caprolactone-lactic acid random copolymer P (CL-co-LA);
• (S2) drying polylactic acid (PLA);
• mixing a dried PLA and the P(CL-co-LA) uniformly followed by melt blending at a temperature of 180-190° C. and a rotation speed of 50-100 r/min to obtain a blend;
• wherein a weight ratio of PLA to P (CL-co-LA) is (9-99):1, and the melt blending is performed for 5-10 min;
• and
• subjecting the blend to compression molding at 180-190° C. and 8-10 MPa to obtain a copolymerized modified PLA finally;
• and
• (S3) subjecting the copolymerized modified PLA, poly(3-hydroxybutyrate-co-3-hydroxyvalerat) (PHBV), nano SiO2, a compatibilizer, and a chain extender to blending obtain a melt-blown blend;
• wherein a weight ratio of the copolymerized modified PLA to the PHBV to the nano SiO2 to the compatibilizer to the chain extender is (80-95):(1-5):(0.1-0.2):(0.001-0.005):(0.001-0.01);
• wherein the compatibilizer is a combination of maleic anhydride, butyric anhydride, stearic anhydride, and tannic acid in a weight ratio of 1:1:1:1;
• feeding the melt-blown blend to a screw extruder followed by melt-extrusion and pelletization at 160-200° C. to obtain a blend pellet;
• and
• feeding the blend pellet to the screw extruder followed by melt-extrusion and plasticization to obtain a melt-extrusion product;
• and transporting the melt-extrusion product to a spinneret assembly, and ejecting the melt-extrusion product from a hole of a spinneret of the spinneret assembly followed by cooling and pulling using hot air flow to form a melt-blown non-woven material on a collecting device, and subjecting the melt-blown non-woven material to electret treatment to obtain the fully degradable non-woven fabric.