METHOD OF OBTAINING ARAMID POWDER, CONTAINING DAPBI Russian patent published in 2009 - IPC C08G69/32 C08G69/46 

FIELD: chemistry.

SUBSTANCE: invention relates to the method of obtaining aromatic polyamide, to aromatic polyamide, containing a link of para - phenyleneterephtalamide and 2-(p-phenylene)benzimidazoleterephtalamide, as well as to the method of obtaining pure aromatic polyamide, suitable for production of spinning solution, used for making fibres and films. The method of producing aromatic polyamide involves copolymerisation of the following components: i) a mol % para-phenylendiamine, ii) b mol % 5(6)-amino-2-(p-aminophenyl)benzimidazole and iii) 90-110 mol % terephthaloylchloride, in a mixture of N-methylpyrrolidone. The N-methylpyrrolidone mixture contains c wt % calcium chloride, where c lies between 1 and 20. The ratio a:b varies from 1:20 to 20:1, a+b=100 mol %. i), ii) and iii) together constitute 1-20 wt % of the mixture. Product of b and c is at least 50 times less than 215. The obtained aromatic polyamide is a powder with relative viscosity ηrel which is at least 4. Powder is defined as non-sticky particles, at least 95% of which have average diametre 0.7-15 mm. The method of producing purified aromatic polyamide involves coagulation of aromatic polyamide, washing the powder in water and drying.

EFFECT: invention allows for obtaining aromatic polyamide with high relative viscosity in form of powder, which can easily be coagulated, washed and dried.

4 cl, 1 tbl