METHOD OF PRODUCING CONTINUOUS FIBRE BASED ON ALUMINIUM OXIDE Russian patent published in 2025 - IPC C04B35/634 C04B35/185 D01F9/10 

FIELD: chemistry.

SUBSTANCE: invention relates to production of continuous fibre Al₂O₃-SiO₂ from high-viscosity fibre-forming solution. Method of producing continuous fibre involves preparation of a fibre-forming solution consisting of a water-soluble organic polymer – polyvinyl alcohol, aluminium oxychloride, silica sol and water, evaporation thereof, forming a multifilament thread from the precursor fibre and thermal treatment thereof. Ratio of aluminium oxychloride and silica sol is calculated based on the required ratio of aluminium and silicon oxides in the finished fibre. Evaporation of the fibre-forming solution is carried out in two steps. At the first stage, the fibre-forming solution is evaporated at pressure of 900 mbar with a gradual decrease to 12 mbar at temperature of 40 to 50 °C until removal of water is 30-40%, after which an aqueous solution of a mixture of polyvinyl alcohol, aluminium oxychloride, silica sol and water is added to the said solution to the initial volume. Further, a second evaporation step is carried out at pressure of 900 mbar with gradual reduction to 12 mbar until 30-60% of water is removed until viscosity of 750 or 800 P.

EFFECT: obtaining multifilament threads from continuous fibre with low irregularity in linear density and defect-free surface, as well as providing high output of solution and fibre from it.

2 cl, 2 dwg, 1 tbl, 4 ex