VINYLIDENE FLUORIDE POLYMER POWDER AND USE THEREOF

• Main Authors: SAKABE, HIROSHI, MIYAHARA, MICHIHISA, SATO, HIROSHI, HORIE, KATSUO, SAKUMA, MITSUYASU
• Format: Patent
• Language: English; French; German
• Published: 24.11.2010
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOSITIONS BASED THEREON; ELECTRICITY; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; THEIR PREPARATION OR CHEMICAL WORKING-UP

A method for producing a vinylidene fluoride based polymer powder having a high molecular weight and excellent solubility in an organic solvent, which is useful as an electrode binder for nonaqueous cells, is provided. Methods for producing an NMP solution and an electrode mixture are also provided. A vinylidene fluoride based polymer powder produced by supercritical suspension polymerization in an aqueous dispersion medium wherein a volume of pores having a pore diameter of 0.03 µm to 1.0 µm, as measured by a mercury porosimeter, is 77 vol% to 93 vol% of a total pore volume and an inherent viscosity is 2.0 dl/g or greater is obtained.