Fluorine and phosphine oxide containing homo and copolyimides

• Fluorine and phosphorous containing diamine monomer was synthesized.
• The new diamine monomer was used to prepare homo- and copolyimides.
• All homopolyimides displayed moderate Tg values but poor film forming properties.
• Copolymerization improved the film forming properties.
• Surface energy of the copolyimides were found to be between 30 and 37.5 mN/m.

In recent years the synthesis of fluorinated polyimides has become an active area of research. In this study perfluoroalkyl and phosphine oxide containing diamine monomer, bis(3,3′-aminophenyl)-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) phosphine oxide (mDA13FAPO), was successfully prepared. mDA13FAPO was reacted with four different commercial dianhydrides (BTDA, PMDA, ODPA and 6FDA) and corresponding homopolyimides were prepared by thermal and solution imidization techniques. However, homopolyimides of mDA13FAPO exhibited poor film forming properties. In order to overcome this problem different amounts of mDA13FAPO containing copolyimides with BTDA and ODA were prepared. The flame retardancy of the copolyimides was examined by limiting oxygen index measurements. The surface energies of the copolyimides were determined by contact angle measurements. mDA13FPO containing homopolyimides exhibited moderate Tg values (194–233 °C), good thermal stability and excellent solubility. The presence of ODA greatly improved the film forming properties and crack-free, creasable copolyimide films were obtained. As the amount of mDA13FAPO was increased, the flame retardancy and the water contact angles of the copolyimides increased while the surface energies and the glass transition temperatures decreased.

Phosphorous containing novel perfluorinated diamine monomer, mDA13FAPO was synthesized and used in the preparation of homo and copolyimides. Due to the fluorous tail of mDA13FAPO polyimides exhibited hydrophobicity with a water contact angle value of 102° and surface energy value of 30 mN/m.Figure optionsDownload as PowerPoint slide