Synthesis of novel fluorinated hyperbranched polyimides with excellent optical properties

Abstract

Novel anhydride‐terminated fluorinated hyperbranched polyimides (FHBPIs) were successfully prepared by condensation of a triamine monomer, 1,3,5‐tris(2‐trifluoromethyl‐4‐aminopheoxy) benzene (TFAPOB), and various aromatic dianhydride monomers with different linear length. UV–vis spectra indicate high optical transparency of FHBPI films with a UV–vis absorption edge of 350–395 nm. FHBPIs show increased mechanical properties with the linear length of dianhydride monomer. Young's moduli of FHBPI range from 2.37 to 2.56 Gpa, similar to those of their linear analogs. These FHBPI films also present a minimum birefringence value as low as 0.0025 at 650 nm and have low optical absorption in the optical communication wavelengths of 1310 and 1550 nm. Rib‐type optical waveguide device fabricated by FHBPI‐4d demonstrated an obvious near‐field mode pattern of the waveguide. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6269–6279, 2009

Aromatic Hyperbranched Polymers: Synthesis and Application

“…The AB 2 monomers self-condensed to form different hb-PAEKs and the T g was 175, 197, or 215 C, depending on whether the repeat unit structure contained biphenyl, terphenyl, or quadriphenyl units in the polymer backbone. C, which was higher than the previously reported T g by Miller et al (140)(141)(142)(143) C) [63]. The hb homopolymer showed a bimodal molecular weight distribution that was also observed for other related linear hb systems.…”

“…The authors observed that hb-PI showed a birefringence as low as 0.002 at 650 nm, which was attributed to the presence of triamine monomers that reduced the orientation of the bonds in the polymer backbone and thereby reduced the birefringence. Liu et al [140] used a nonideal A 2 + B 3 polymerization approach to obtain fluorinated hb-PIs based on TFAPOB. A series of aromatic ether dianhydride monomers with different flexible linear lengths were used to overcome the poor mechanical properties of globular branched macromolecules.…”

“…The monomer combination of A 2 + B 3 monomers is shown in Table 3, entry 3. The reaction temperature of most experiments was kept at [140][141][142][143][144][145] C to allow for a comparison with the experiments performed in DMSO and to keep minimum chain scission. The silyl method required longer reaction times than the standard method because the concentration of active end groups (phenoxide ions activated by K 2 CO 3 ) was significantly lower when silylated monomers were used.…”

Synthesis and properties of novel hyperbranched polyimides end‐capped with metallophthalocyanines

“…They were first developed as industrial pigments, and have been diversely applied in various fields including chemical sensors, solar cells, catalysis, liquid crystals, and photodynamic therapy (PDT), 2-7 due to their stability, diverse coordination properties and optical properties. [14][15][16][17][18] Recently, our group have explored several PAEKs which contained metallophthalocyanine, here, we prepared a hyperbranched polyimide end-capped with metallophthalocyanine. [9][10][11][12] However, it is difficult for most phthalocyanine compounds to dissolve and to melt, which results in the restriction in their applications.…”

Research on flexible display at Ulsan National Institute of Science and Technology

“…The important properties of flexible substrates are mechanical flexibility, thermal stability, optical transparency, and gas barrier properties. [34][35][36] Generally, typical materials for flexible substrates are polymer-based solid materials such as polyethylene terephthalate, 34 polyethylene naphthalate, 35 and PI. 36 Exceptionally, thin glass (thickness =~100 μm) has been used for flexible substrates, 37 however such thin glass (to the best of our knowledge) is still brittle under some forms of mechanical deformation.…”