| 초록 |
New fluorinated polyurethane elastomers were synthesized by two step polymerization of the fluorinated polyols based on poly(VDF-co-HFP) and diisocyanate such as MDI in DMAc, followed by subsequent chain extension with low molecular weight diol such as BDO. In order to control the fluorinated polyol moiety of the soft segment in the synthesized elastomer in the range of 1∼10mol%, polyether type polyols such as PPG and PTMG with Mn 2,000 were mixed together during the polymerization reaction. In order to compare with the relationship between conventional fluorinated polyurethanes and new fluorinated polyurethanes, fluorinated polyurethanes containing perfluorinated polyether diol and non-fluorinated polyurethanes were synthesized. The surface properties were analyzed by contact angle meter. Tensile properties were carried out by Instron 4467. Prior to synthesize of fluorinated polyurethanes, The well-defined α,ω-diiodo-poly(VDF-co-HFP) with narrow unimodal molecular weight distribution(PDI=1.05-1.3) was polymerized by Iodine Transfer Polymerization(ITP) These α,ω-diiodo-poly(VDF-co-HFP) were converted to α,ω-bis(hydroxyethyl)-poly(VDF-co-HFP) followed by the hydrolysis using water. structure and functionality of these dihydroxy fluoro polymers were characterized by 1H-NMR, 13C-NMR, 19F-NMR and end-group titration and showed high conversion. As these fluorinated polyol with the molecular weight below 4,000g/mol were used as telechelic fluorinated prepolymer for the sythesis of fluorinated polyurethane with low surface energy, good physical properties. |
