Crystallization kinetics of a fluorinated copolymer of tetrafluoroethylene

The so-called “fluoropolymers” gained in recent years a considerable industrial success, and the increasing industrial interest to this class of materials causes a need of a better characterization of the properties of interest for processability. In this work, the crystallisation kinetics of a Fluorinated Copolymer of Tetrafluoroethylene (MFA, produced by Solvay), was studied by both standard calorimetric tests and fast cooling tests performed by an apparatus which allows on line determination of crystallisation phenomena. Material crystallisation kinetics resulted to be so fast that the polymer reached the maximum degree of crystallisation for all solidification conditions, also those obtained at cooling rates of the order of hundreds of degrees per second. Calorimetric tests also gave indications about the dependence of maximum crystallinity degree upon temperature. The crystallisation kinetics was described by the non-isothermal formulation due to Nakamura of the well-known Avrami equation. Results were compared with experimental data.