发明名称 |
PROCESS FOR PRODUCING PURIFIED POLYTETRAFLUOROETHYLENE AQUEOUS-DISPERSION |
摘要 |
A process for producing an aqueous dispersion of purified polytetrafluoroethylene (PTFE), comprising passing a crude aqueous dispersion of PTFE comprising from 10 to 50 mass% of PTFE fine particles having an average particle diameter of from 0.1 to 0.5 µm, from 0.05 to 1.0 mass%, based on PTFE, of a fluorine-containing carboxylic acid salt (APFO) and from 2 to 20 mass%, based on PTFE, of a nonionic surfactant through a column packed with a weak basic AER upward at a linear velocity of 0.1 to 2 mm/sec with a contact time of 0.2 to 4 hours to reduce the APFO concentration. The process can increase the absorption of APFO by the anion exchange resin, prevents agglomeration of PTFE during passage and makes it easy to elute the absorbed APFO.
|
申请公布号 |
EP1916263(A1) |
申请公布日期 |
2008.04.30 |
申请号 |
EP20050806823 |
申请日期 |
2005.11.17 |
申请人 |
ASAHI GLASS COMPANY, LIMITED |
发明人 |
HOSHIKAWA, JUN;HIGUCHI, SHINYA;MATSUOKA, YASUHIKO |
分类号 |
C08F6/16;C08F14/26;C08J3/03;C08L27/18 |
主分类号 |
C08F6/16 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|