ARAMID FIBRILS Russian patent published in 2009 - IPC D01F6/60 D21H13/26 

FIELD: textile; paper.

SUBSTANCE: invention concerns obtainment of para-aramid fibrils, as well as paper based on the claimed fibrils. In humid phase poly(para-phenylethylene terephthalamide) fibrils show drainage rate by Canada Standard under 100 ml, specific surface area after drying under 7 m²/g and weight-average particle length under 1.2 mm, defined respective of weight for particles over >250 mcm long (WL_0.25). Method of fibril obtainment involves polymerisation of aromatic diamine and aromatic dicarboxylic acid haloid up to para-aramide polymer stage in the mix of N-methylpyrrolidone or dimethylacetamide and calcium or lithium chloride to obtain spinning solution. Concentration of polymer dissolved in the mix is 2-6 wt %. Obtained spinning solution is transformed into fibrils by spinning nozzle in gas flow, and fibril coagulation is performed by coagulation jet. Paper is made of components where at least 2 wt % corresponds to the claimed para-aramide fibrils.

EFFECT: large breaking length of the paper obtained; simple implementation of the fibril obtainment method, issue of equipment corrosion solved.

7 cl, 3 tbl, 4 ex