Solvay Solexis S.p.a.

Ausimont S.p.a.

Stefano Ferrero

Valeri Kapeliouchko

Vincenzo Arcella

Marco Malvasi

Hua Wu

Evasio Deregibus

Aniello Gargiulo

A fluoropolymer [polymer (F)], a polymerisation process for its manufacture, and a molding process using such fluoropolymer [polymer (F)]. The polymerisation process comprises polymerising at least one fluorinated monomer in a polymerization medium, in which the polymerization medium is mixed by means of a stirring system comprising at least two counter-rotating impellers. Surprisingly and advantageously, the polymerization occurs without fouling or deposit formation on the reactor walls, and moreover, occurs with improved homogeneity, without composition, pressure or temperature gradients, thus enabling obtaining homogeneous polymer composition with no risk of local overheating. A polymer (F) obtained from such process has improved morphology (percentage of organized structures, i.e. of particles of regular shape) and, hence, has good free flowing properties which make it suitable for being processed by compression molding with no need of intermediate milling or grinding process or other size reduction process.

Polymerisation process

Fine fluoropolymer powders substantially fluorinated surfactant free, in particular fluorinated ionic surfactants, preferably perfluorooctanoic acid or its salts, comprising an anionic polyelectrolyte.

Fine fluoropolymer powders

An elimination process of fluorinated anionic sufactants from exhausted gaseous streams, wherein the gaseous stream is put into contact with aqueous solutions having in the range from 3.5 to 13.8, the aqueous solution density being lower than 1.05 g/cm, wherein the concentration in the aqueous solution of the fluorinated anionic surfactant removed by the gaseous stream is lower than or equal to 70 ppm.

Elimination process of fluorinated anionic surfactants

Coagulation process of PTFE fine powders

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Alessandria, Italy

Stefano Ferrero