Poly(vinylidene fluoride)/Polymethylene-Based Block Copolymers and Terpolymers

Dual crystalline diblock copolymers consisting of polymethylene (PM) and poly­(vinylidene fluoride) (PVDF) blocks as well as triblock terpolymers with polystyrene (PS) as middle block were synthesized. For the synthesis, two/three different polymerization methods such as polyhomologation, atom transfer radical polymerization (ATRP), and iodine transfer polymerization (ITP) along with chain-end postpolymerization reactions were employed. Solid-state NMR spectroscopy revealed the characteristic peaks of all constituent blocks while gel permeation chromatography (GPC) results demonstrated the controlling/living nature of all implemented polymerization methods. The analysis of crystallization behavior based on differential scanning calorimetry (DSC) indicates the presence of different PVDF crystalline phases (α, β, and γ) n block copolymers. Further analysis with X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopies revealed the coexistence of α- and β-phases in diblock copolymers and β- and γ-phases in triblock terpolymer. An initial study of self-assembly in DMF, a selective solvent for PVDF and PS, was performed by dynamic light scattering (DLS) and atomic force microscopy (AFM)