FIELD: chemistry.
SUBSTANCE: present invention relates to a group of inventions: a method for producing an aqueous dispersion of purified polytetrafluoroethylene (PTFE), a method for producing powdered purified PTFE, a method for producing a moulded body from PTFE, a method for producing purified PTFE, a method for producing PTFE, a composition for moulding a moulded body, a composition for moulding a moulded body, a composition for moulding a moulded body, a composition for moulding a moulded body, and a moulded body. Method for producing an aqueous dispersion of purified PTFE includes removal or reduction of the content of the compound (1) (H-(CF2)m-COO) pM1 or (2) (H-(CF2)n-SO3)qM2 in an aqueous dispersion of PTFE produced by conducting emulsion polymerisation of tetrafluoroethylene (TFE) in an aqueous medium in the presence of a hydrocarbon surface-active substance (surfactant). The method for producing powdered purified PTFE includes removal or reduction of the content of the compound (1) or (2) in powdered PTFE produced by emulsion polymerisation of TFE in an aqueous medium in the presence of a hydrocarbon surfactant. A method for producing a moulded body from PTFE produced by emulsion polymerisation of TFE in an aqueous medium in the presence of a hydrocarbon surfactant, wherein the method includes removal or reduction of the content of the compound (1) or (2). The method for producing purified PTFE includes removal or reduction of the content of the compound (1) or (2) as a result of introduction of a fluorine radical source into contact with PTFE produced using a hydrocarbon surfactant at a temperature of 100 to 310°C. The method for producing PTFE includes removal or reduction of the content of the compound (1) or (2) as a result of introduction of a fluorine radical source into contact with PTFE produced using a hydrocarbon surfactant, wherein the amount of added fluorine radical source is in the range from 0.5 to 35.0 wt.pts. per 100 wt.pts. PTFE as applied to fluorine atoms. The composition for moulding a moulded body comprises PTFE, the compound (H-(CF2)13-COO)pM1 (5), a nonionic surfactant, and substantially does not contain the compound (3) (H-(CF2)8-SO3)qM2. The composition for moulding a moulded body comprises PTFE and any single compound selected from compound (5) (H-(CF2)13-COO)pM1 and compound (5’) (H-(CF2)14-COO-)pM1, a nonionic surfactant, and substantially does not contain the compound (3).
EFFECT: production of an aqueous dispersion of PTFE and powdered PTFE while removing the compound containing fluorine or reducing the content thereof; production of a moulded body from PTFE using PTFE; production of a composition.
21 cl, 18 tbl, 54 ex
