title: UV-curable low surface energy fluorinated polycarbonate-based polyurethane dispersion.
abstract: UV-curable low surface energy fluorinated polycarbonate-based polyurethane dispersions were synthesized by incorporating a hydroxy-terminated perfluoropolyether (PFPE) into the soft segment of polyurethane. The effects of the PFPE content on the UV-curing behavior, physical, surface, thermal properties and refractive index were investigated. The UV-curing behavior was analyzed by photo-differential scanning calorimetry. The surface free energy of the UV-cured film, which is related to the water or oil repellency, was calculated from contact angle measurements using the Lewis acid-base three liquids method. The surface free energy decreased significantly with increasing fluorine concentration because PFPE in the soft segment was tailored to the surface and produced a UV-cured film with a hydrophobic fluorine enriched surface, as confirmed by X-ray photoelectron spectroscopy. With increasing the fluorine content, the refractive indices of UV-cured films decreased. However, the UV-curing rate and final conversion was decreased with increasing contents of PFPE, which resulted in the decrease of the glass transition temperature (T(g)), crosslink density, tensile strength and surface hardness.
authors.affiliation: Lab. of Adhesion and Bio-Composites, Program in Environmental Materials Science, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Hyeon-Deuk
authors.initials: HD
authors.lastname: Hwang
authors.forename: Hyun-Joong
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D003102:Colloids / Q000737:chemistry*; D005466:Fluorocarbons / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D054879:Halogenation; D008422:Materials Testing / Q000379:methods; D011076:Polycarboxylate Cement / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D013499:Surface Properties; D044366:Transition Temperature; D014466:Ultraviolet Rays
chemical_list: D003102:Colloids; D005466:Fluorocarbons; D011076:Polycarboxylate Cement; D011140:Polyurethanes; C005506:polycarbonate