Sheath-core flame retardant filament and preparation method thereof

[0042] A preparation method of a skin-core flame-retardant filament, the steps of which are as follows:

[0043] (1) prepare MgO powder;

[0044] First heat MgO to 400°C and keep it warm for 2 hours, then raise the temperature to 700°C and keep it warm for 1 hour, then cool it in the air, and finally pulverize it to obtain MgO powder with an average particle size of 0.49 microns;

[0045] (2) prepare polyester;

[0046] (2.1) Esterification reaction;

[0047] Make slurry with terephthalic acid, ethylene glycol and 2-carboxyethylphenylphosphinic acid at a molar ratio of 1:1.2:0.03, add MgO powder, antimony trioxide, titanium dioxide and trimethyl phosphate and mix well Finally, the esterification reaction is carried out under pressure in a nitrogen atmosphere. The pressurized pressure is 0.3 MPa, and the temperature of the esterification reaction is 250 ° C. When the amount of water distilled in the esterification reaction reaches 90.1% of the theoretical value, it is an esterif

[0056] A preparation method of a skin-core flame-retardant filament, the steps of which are as follows:

[0057] (1) prepare BaO powder;

[0058] First heat BaO to 400°C and keep it warm for 3 hours, then raise the temperature to 700°C and keep it warm for 2 hours, then cool it in the air, and finally pulverize it to obtain BaO powder with an average particle size of 0.45 microns;

[0059] (2) prepare polyester;

[0060] (2.1) Esterification reaction;

[0061] Make slurry with terephthalic acid, ethylene glycol and 2-carboxyethylphenylphosphorous acid at a molar ratio of 1:2.0:0.032, add BaO powder, antimony ethylene glycol, titanium dioxide and triphenyl phosphate and mix well Finally, the esterification reaction is carried out under pressure in a nitrogen atmosphere. The pressurized pressure is 0.2 MPa, and the temperature of the esterification reaction is 260 ° C. When the amount of water distilled in the esterification reaction reaches 95% of the theoretical value, it is an

[0068] A preparation method of a skin-core flame-retardant filament, the steps of which are as follows:

[0069] (1) Preparation of SiO 2 - BaO powder;

[0070] First heat the SiO 2 -BaO is kept at 400°C for 2.5 hours, then heated to 700°C, held for 1.5 hours, cooled in air, and finally crushed to obtain SiO with an average particle size of 0.48 microns 2 - BaO powder, SiO 2 -The content of BaO in BaO is 40wt%;

[0071] (2) prepare polyester;

[0072] (2.1) Esterification reaction;

[0073] Make a slurry of terephthalic acid, ethylene glycol and 2-carboxyethylphenylphosphorous acid at a molar ratio of 1:1.6:0.035, and add SiO 2 -After BaO powder, antimony acetate, titanium dioxide and trimethyl phosphite are mixed evenly, the esterification reaction is carried out under normal pressure in a nitrogen atmosphere. The temperature of the esterification reaction is 255 ° C. When the water in the esterification reaction is distilled When the amount reaches 92% of the theoretical