Polydimethylsiloxane- (PDMS-) grafted fluorocopolymers by a "grafting through" strategy based on atom transfer radical (Co)polymerization

Three types of PDMS-grafted fluorocopolymers with various branching features were synthesized based on atom transfer radical polymerization (ATRP) techniques via a "grafting through" approach using methacryloxypropyl-terminated PDMS (PDMSMA) as macromonomer. Copolymers 1, with a linear fluorinated backbone and linear PDMS grafts, were prepared by copolymerizations of 2,3,4,5,6-pentafluorostyrene (PFS) with PDMSMA. Copolymers 2, with a hyperbranched fluorinated backbone and linear PDMS-based grafts, were prepared by self-condensing vinyl copolymerization (SCVCP) of an inimer, p-chloromethylstyrene (CMS), with PFS and PDMSMA. Copolymers 3, with a hyperbranched fluorinated core and linear PDMS grafts, were prepared by ATRP of PDMSMA, initiated by benzylic chloride-functionalized hyperbranched fluorocopolymer (obtained by SCVCP of PFS and CMS). A series of characterization methods, including ¹H, ¹³C, and ¹⁹F NMR spectroscopies, gel permeation chromatography, elemental analysis, thermogravimetric analysis, and solubility tests, were used to investigate the reaction kinetics, and the compositions, molecular weights, and properties of these copolymers.