| 摘要 |
PURPOSE:To obtain the titled precursor having high strength free from yarn defect, by feeding raw materials such as a monomer, e.g., acrylonitrile, etc., a catalyst, a solvent, etc. subjected to fine filtration, containing substantially no impurity, to a polymerization system, and spinning it. CONSTITUTION:(A) A polymerizable unsaturated monomer containing preferably >=95wt% acrylonitrile, (B) a polymerization initiator [e.g., redox initiator such as (NH4)2S2O3/NH4HSO3, etc.], (C) an aqueous solution of other auxiliaries, and (D) a solvent (e.g., DMF, etc.) for preparing a stock solution are subjected to fine filtration treatment using a filtering medium such as fluoro pore made of polytetrafluoroethylene having <=0.1mu open pore diameter. The prepared raw materials containing substantially no impurity are fed to a polymerization system, polymerized, the formed polymer is spun, to give the aimed precursor. Preferably 0.5-3wt% carboxyl group-containing unsaturated monomer (e.g., acrylic acid, etc.) as an agent for flameproofing rate promoting effect is added to the raw material A.
|
