9,9-Diarylfluorene-Based Poly(alkyl aryl ether)s: Synthesis and Property

Abstract

Polyethers possessing 9,9-diarylfluorene moieties in the main chain (F-PEs 3) were synthesized in 85-99% yields by the polycondensation of 9,9-bis(hydroxyaryl)fluorenes with alkyl ditosylates in the presence of cesium carbonate. Molecular weight of the F-PEs was dependent on the structure of the ditosylate 1; cyclohexyl-1,4-dimethylene (1a), 1,2-ethylene (1b), 1,3-trimethylene (1c), and 1,6-hexamethylene (1d). Higher molecular weight F-PEs (M n 32000-60000, M w 74000-160000) was obtained when longer alkyl chain ditosylates (1a and 1d) were used. The F-PEs showed good solubility toward various organic solvents such as toluene and high 5% weight loss temperature (T d5 : 424-447 C). The glass transition temperature of F-PEs (T g ) was ranging from 147 to 220 C. No melting point (T m ) was observed. F-PEs showed high water-resistance. The transmittance of F-PEs in film state (thickness: 21-32 mm) reached over 90% in the visible region. The F-PEs exhibited high refractive indices in a range of 1.62-1.66 at 590 nm in addition to sufficiently low birefringence values, probably due to the cardo structure of the fluorene moiety placed in the main chain. The structural dependence of dispersing ability to fullerene C 60 was investigated.KEY WORDS: Cardo Structure / Polyether / Refractive Index / Birefringence / Solubility / Thermal Stability / Processability / 9,9-Diarylfluorene-based polymers attract much attention due to the unique characteristics originated from the ''cardo'' structure as characterized often by the high refractive index and low birefringence.1-9 Such optical property is caused by the presence of many aromatic rings in the 9,9-diarylfluorene moiety which occupy the different planes to disturb the interchromophore packing, effectively decreasing the optical anisotropy. Meanwhile, such polymers also display excellent filler-dispersing ability [10][11][12] in addition to their high thermal stability, [13][14][15][16] high solubility, [17][18][19] and so on. [20][21][22][23][24][25] We have recently reported the special -interaction of the 9,9-diarylfluorene moiety in the matrix polymers toward -face of the carbon fillers.26 Although many polymers possessing 9,9-diarylfluorene moieties in the main chain have been developed to date, there is no study on polyethers. Polyethers are an important class of high performance engineering thermoplastics with a favorable combination of physical, mechanical, and chemical properties, other than processability, [31][32][33][34][35][36][37][38][39][40][41] and are easily synthesized usually by the polycondensation of diols and ditopic electrophiles. Polyethers with good optical and physical properties can be obtained, 42,43 if saturated alkyl group is introduced into the polymer main chain in addition to 9,9-diarylfluorene moiety, because the alkyl group often shows no optical anisotropy.Herein, we wish to disclose the synthesis and property of poly(alkyl aryl ether)s (F-PEs) containing 9,9-diarylfluorene moiety in the main chain, with emphasis on the effect of alkyl chai...

Synthesis of Cardo Based Poly(arylene ether)s for Flexible Plastic Substrates and Their Properties

“…[6][7][8] In this paper, we explore new PAEs with both transparency and improved thermal properties.…”

Synthesis and properties of pendant fluorene moiety-tethered aliphatic polycarbonates

“…Furthermore, some of them have good processability because of their appropriate glass transition and high decomposition temperatures, as well as good solubility in organic solvents. 1,2 We have long studied the synthesis and properties of many cardo polymers having 9,9-diarylfluorene moieties [3][4][5][6][7][8][9][10][11][12][13][14][15][16] and recently reported the preparation of cardo-like polymers [17][18][19][20][21] that have 9,9′-spirobifluorene moieties as the main chain units. Most cardo polymers hitherto studied have been aromatic, whereas aliphatic cardo polymers, 'cardo carbochain polymers' as defined by Korshak, 1 are also interesting because of their expected moderate properties based on their flexible main chains, although only a few reports dealing with fluorenecontaining polymers or oligomers have been reported so far, to the best of our knowledge.…”

9,9-Diaryl-4,5-diazafluorene-based Cardo polymer; Synthesis and characteristic properties

“…As 9,9‐diarylfluorene ( DAF )‐based polymers exhibit unique properties such as high thermal stability, high solubility in organic solvents, amorphous nature, high filler‐dispersing ability, high refractive index, and low birefringence, they have attracted considerable interests in the field of high‐performance polymer materials such as optical materials, gas permselective film, high filler dispersible matrix polymer, heat‐resistance resin, and so forth . These excellent properties are attributed to the cardo structure of DAF in which aryl substituents at the quaternary carbon center of alicyclic moiety occupy different planes [Fig.…”

“…(a)]. To explore the useful derivatives of DAF ‐based polymers, we have previously reported the synthesis of modified cardo structure‐based polymers such as silafluorene‐type cardo polymer, sulfur‐containing polymers, 9,9′‐spirobifluorene‐based polymers, and their excellent properties such as higher thermal stability, higher refractive index, and lower birefringence than those of the corresponding DAF ‐containing polymers. We have recently focused our attention on the fusion of 4,5‐diazafluorene into a new cardo structure.…”