Teijin Aramid B.v.

Jan Davis Cornelis Tiecken

Mirjam Ellen Oldenzeel

Anton Johannes Josef Hendriks

René Journee

Harrie Grotendorst

Aramid fibrils having in the wet phase a Canadian Standard Freeness (CSF) value less than 100 ml, after drying a specific surface area (SSA) less than 7 m/g, and a weight weighted length for particles having a length &#x3e;250 &#x3bc;m (WL 0.25) less than 1.2 mm, are described. A method of preparing the fibrils includes the steps (a) polymerizing an aromatic diamine and an aromatic dicarboxylic acid halide to an aramid polymer, in a mixture of N-methylpyrrolidone or dimethylacetamide and calcium chloride or lithium chloride to obtain a dope wherein the polymer is dissolved in the mixture and the polymer concentration is 2 to 6 wt. %, (b) converting the dope to fibrils by using a jet spin nozzle under a gas stream, and (c) coagulating the fibrils using a coagulation jet.

Growing community of inventors

Didam, Netherlands

Jan Davis Cornelis Tiecken