Synthesis of urethane graft copolymers with perfluoroalkyl and silicone-containing side chains and their surface properties

Abstract

Dihydroxyl-terminated macromonomers with two groups, a perfluoroalkyl group and a silicone-containing group, were synthesized by free-radical polymerization with perfluoroalkylethyl acrylate (FA), 3-[tris(trimethylsilyloxy)silyl] propyl methacrylate (SiMA), and 1-thioglycerol (TG). Using these macromonomers and toluene-2,4-diisocyanate (TDI), various urethane graft-co-(septadecafluorodecylacrylate)-(tris(trimetylsiloxy silylpropyl acrylate) copolymers (PUFSGs) with differing FA and SiMA contents were synthesized. The macromonomers and PUFSGs synthesized were characterized and identified by GPC, DSC, (X-ray photoelectron spectroscopy (XPS), FTIR, and 1 H-NMR analysis. The surface free energies of PUFSGs, 9 -12 dynes/cm, depend strongly on FA content but not on SiMA content. The glass transition temperature of PUFSG is strongly dependent on SiMA content. The perfluoroalkyl group originating from FA is preferentially arranged to the outermost layer at the air-polymer interface to the silicone-containing group originating from SiMA. The surface free energies of PUFSG/polyvinyl chloride (PVC) blends exhibit extremely low values, 10 -14 dynes/cm, indicating that extreme segregation of PUFSG occurs at the air-polymer interface. Most PUFSGs added to PVC are located at the air-polymer interface, and PUFSGs are very effective in lowering the surface free energy.

The lower surface free energy achievements from ladder polysilsesquioxanes with fluorinated side chains

“…Some effort by incorporation silicone into the polymer side chain to reduce the surface tension was reported [4], however, the improvement was rather limited and less significant than that of the fluorinated side groups. By incorporation of fluorine into the polymer chain [5], blending fluoropolymers with hydrocarbon [6], chemically grafting perfluoroalkyl groups to polymers [7], polymers with lower surface tension could be obtained.…”

Fluorosilicones and Other Fluoropolymers

“…Kim et al [40] synthesized a fluorosilicone polymer with a hydrocarbon backbone and fluorinated and siloxane pendant groups covalently bound by urethane. The structure of urethane graft-co-(septadecafluorodecylacrylate)-[tris(trimethyl Scheme 6.8 General structures of fluorinated chiral LCEs.…”

Preparation and properties of polydimethylsiloxane (PDMS)/polytetramethyleneadipate glycol (PTAd)‐based waterborne polyurethane adhesives: Effect of PDMS molecular weight and content

“…To attain better and specific physical properties, a mixed or special type of polyol was used in WBPUs. Moreover, various methods such as hydrophobic monomers grafted to polyurethane (PU) main chain,14, 15 the change of the type and content of ionic center,16–18 the adjustment of ionic neutralization degree,19–21 the blending22–24 and copolymerization of different polymers,25–29 and cross‐linking30, 31 have been employed to improve the properties of WBPU.…”