METHOD FOR PRODUCING POLYAMIDE ACID BASED ADDITIVE AND COMPOSITIONS FOR MAKING ANTIADHESIVE, NON-STICK AND ANTIFRICTION COATINGS FOR METAL SURFACES Russian patent published in 2015 - IPC C08G73/10 C09D127/18 C09D5/08 C09D5/00 C08J5/16 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical industry and concerns a method for producing an additive in the form of hard fibres, wherein the said additive is storage stable and based on the eco-friendly polyamide acid; the said additive in a salt state can be used for the production of composite materials and metal coatings. The method for polyamide acid salt production comprises forming a polyamide acid fibre cocoon by mixing 13.0-13.5 wt % polyamide acid solution in dimethylformamide with distilled water while stirring at the rate of 50 rev/min. The obtained cocoon is washed with distilled water, and separated into individual fibres to dry in the air and then at 120-130°C for 60 min in a cabinet drier, in a vacuum thermostat at 79-81°C and a pressure of 1 atm. to reduce dimethylformamide content down to 3.68 wt %, followed by dissolving the fibres in a mixture of N-methylpyrrolidone, monoethanolamine and water to obtain the said salt. A method for producing coatings based on fluoropolymers with polyamide acid salt or polyamide acid-based lacquer.is also disclosed.

EFFECT: storage stable polyamide acid in the form of fibres, improved quality of polyamide acid and composite materials based on fluoropolymers and polyamide acid, improved antiadhesive and antifriction coatings.

3 cl, 2 tbl, 2 ex