Patent ID: 9334586
Filing Date: 2016-05-10
CPC Classification: B05D,D01D,D01F,D02J,D10B

Claim Text:
1. A melt spinning process for producing a PAN-based pre-oxidized fibre, comprising the following steps: a) dissolving a catalyst for pre-oxidation of PAN in an ionic liquid in a weight ratio from 1:100 to 0.01:100 followed by adding PAN powder to obtain a mixture, wherein the weight ratio of PAN powder to ionic liquid is between 1:1 and 1:0.25; b) adding the mixture from step a) to a hopper of twin-screw spinning machine to conduct melting spinning while blowing an oxygen-containing gas into a melting segment of the twin-screw spinning machine, wherein the flow rate of the oxygen-containing gas is between 1 ml/min and 5 ml/min, and the rotational velocity of screw is between 40 and 120 r/min, and the temperature at a feed segment is between 170° C. and 185° C., and the temperature for plasticizing is between 185° C. and 220° C., and the temperature for melting is between 185° C. and 220° C.; c) dry-heat drawing the spun fibre directly under a temperature between 110 and 140° C. with a total draw ratio between 4 and 6, then washing the drawn fibre with water at 70-90° C., followed by thermosetting in dry hot air at 120-150° C. to give the PAN based pre-oxidized fibre.