Detailed copolymerization propagation kinetics of homogeneous phase VDF–HFP copolymerization in supercritical CO2

• Propagation rate coefficients are reported for VDF–HFP copolymers for a wide range of monomer feed compositions.
• A master equation for calculation of copolymerization propagation rate coefficients is provided.
• Mark-Houwink constants are provided allowing for the determination of absolute molecular weights for VDF–HFP copolymers.
• A genetic algorithm was applied to kinetic data.

Propagation kinetics of vinylidene fluoride (VDF)–hexafluoropropene copolymerizations were studied applying pulsed laser initiated polymerizations. The copolymers obtained for VDF monomer feed compositions, fVDF, ranging from 0.31 to 0.81, temperatures up to 90 °C, and pressures up to 1050 bar were analyzed by size-exclusion chromatography. To derive absolute molecular weights Mark-Houwink parameters were determined for each copolymer composition. A genetic algorithm was used to establish a master equation, which describes the variation of the copolymerization propagation rate coefficients as a function of fVDF, pressure, and temperature.

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