PROCESS FOR PRODUCTION OF AQUEOUS POLYTETRAFLUOROETHYLENE DISPERSION FOR COAGULATION PROCESSING, AND AQUEOUS POLYTETRAFLUOROETHYLENE DISPERSION FOR COAGULATION PROCESSING
申请人:Asahi Glass Company, Limited
公开号:EP2489692A1
公开(公告)日:2012-08-22
To provide a process for producing an aqueous PTFE dispersion for coagulation processing, whereby it is possible to efficiently produce an aqueous PTFE dispersion for coagulation processing excellent in coagulation properties of PTFE microparticles, and such an aqueous PTFE dispersion for coagulation processing. A synthetic adsorbent having a specific surface area of from 100 to 2,000 m2/g, is added to an aqueous PTFE dispersion containing from 45 to 70 mass% of PTFE microparticles having an average particle size of from 0.10 to 0.50 µm and from 2.2 to 6 mass%, based on the mass of the PTFE microparticles, of a nonionic surfactant, in a proportion of from 0.5 to 15 mass%, based on the mass of the PTFE microparticles, followed by stirring or shaking and then by separation into a liquid phase and a solid phase, and recovering an aqueous PTFE dispersion for coagulation processing which contains from 45 to 70 mass% of PTFE microparticles having an average particle size of from 0.10 to 0.50 µm and from 1.4 to 2.1 mass%, based on the mass of the PTFE microparticles, of a nonionic surfactant.
提供一种用于凝固处理的聚四氟乙烯水性分散液的生产工艺,据此可以高效地生产出一种凝固处理用聚四氟乙烯水性分散液,该分散液具有优异的聚四氟乙烯微粒凝固特性,以及这种凝固处理用聚四氟乙烯水性分散液。将比表面积为 100 至 2,000 m2/g 的合成吸附剂加入到水性聚四氟乙烯分散液中,该分散液含有 45 至 70 质量%的聚四氟乙烯微粒,其平均粒径为 0.10 至 0.50 微米,以及 2.2 至 6 质量%的非离子表面活性剂(基于聚四氟乙烯微粒的质量),其比例为 0.5 至 15 质量%(基于聚四氟乙烯微粒的质量)。根据 PTFE 微颗粒的质量,以 0.5 至 15 质量%的比例加入非离子表面活性剂,然后搅拌或摇动,再分离成液相和固相,最后回收用于凝固处理的 PTFE 水分散液,该分散液含有 45 至 70 质量%的 PTFE 微颗粒,其平均粒径为 0.10 至 0.50 µm,以及 1.4 至 2.1 质量%的非离子表面活性剂(以 PTFE 微颗粒的质量为基准)。