Hexafluoroisopropylidene diphthalic anhydride

Hexafluoroisopropylidene dianiline was dissolved in DMAc and then treated with the dropwise addition of 4,4 -hexafluoroisopropylidene diphthalic anhydride at ambient temperature. The 20 to 25 wt% solution was next stirred 6 to 8 hours until high molecular polyamic acids were formed. The mixture was treated with a large excess of triethylamine and acetic anhydride and dehydrated by heating to 50°C for 2 to 3 hours and at 100°C to 110° C for 10 to 20 minutes then cooled to ambient temperature. The viscous solution was slowly poured into methanol, and the precipitate was homogenized in a blender. It was then filtered and washed several times with fresh methanol. The material was dried for 12 hours at ambient temperature and 24 hours under vacuum at 250°C, and the product was isolated. 

Finally, two Al-neutralized copolyimides from (4,4 -hexafluoroisopropylidene) diphthalic anhydride, (4,4 -hexafluoroisopropylidene) dianiline, and 3,5-diaminobenzoic acid exhibit a variety of aggregate shapes and sizes that have not been previously observed or even postulated. Scanning TEM shows Al-rich aggregates in both copolymers, but the aggregate size and shape distributions in the ionomer with a high ionic fraction are much more heterogenous than in the ionomer with a lower ionic fraction. This is despite... 

Soluble polyimide prepared by reaction of 4,4 -hexafluoroisopropylidene diphthalic anhydride (6F) with 3,5-diaminobenzoic acid. b Soluble polyimide prepared by reaction of (6F) with 1,5-diaminonaphthalene. c Soluble polyimide prepared by reaction of (6 F) with 1,4-diaminobenzene. d Poly(para-xylylene) Union Carbide Reg. trademark. e Dupont 100 CA-43. f Union Carbide Sulfone 47. 

Intrinsically microporous Pis have been prepared from 2,2 -diamino-l,l -binaphthalene or 4,4 -(9-fluorenylidene)dianiline. As anhydrides pyromel-litic dianhydride, 3,3, 4,4 -biphenyltetracarboxylic dianhydride, 4,4 -oxydiphthalic anhydride, and 4,4 -(hexafluoroisopropylidene)diphthalic anhydride were used [81]. 

Poly(imide-siloxane)s copolymers have been prepared by the reaction of 4,4 -(4,4 -isopropylidene-diphenoxy)bis(phthalic anhydride), 4,4 -oxydiani-line, and an amino-propyl terminated poly(dimethyl-siloxane) [12]. The polymers exhibit a good solubility in various organic solvents. In addition, 4,4 -(hexafluoroisopropylidene)diphthalic anhydride was used as hard block segment [84]. 

The thermal rearrangement of a-hydroxyl-PI membranes improves the gas permselectivity properties in comparison to a neat PI. By intro-dueing segments within the polymer that do not undergo thermal rearrangement, the gas separation properties of the thermally rearranged membrane can be modified. PI copolymers based on 4,4 -hexafluoroisopropylidene diphthalic anhydride and diamines 3,3 -dihydroxy-4,4 -diamino-biphenyI with 2,3,5,6-tetramethyI-l,4-phenyIenediamine or 9,9 -bis(4-aminophenyl)fluorene, thermally rearranged into poly(benzoxazole-co-imide), were tested [107]. 

Figure 7.9 Interfacial polymerization reaction taking place between a Cd-based metal organic framework and a 6FDA-based polyimide. 6FDA, 4,4 -(Hexafluoroisopropylidene)diphthalic anhydride ODA, oxydianiline...

Suda et al. [288] reported the synthesis and characterization of a series of sulfonated star-hb polyimides (S-hb-Pls) without any crosslinking for use as proton exchange membranes. Sulfonated anhydride-terminated polyimides with different molecular weights (M v = 59,000, 200,000 and 300,000 Da) based on monomer combination 1,4,5,8-naphthalene tetracarboxylic dianhydride/4,4 -diaminobiphenyl 2,2 -disulfonic acid (NTDA/BDSA) were synthesized using different molar ratios of BDSA NTDA. The amine-terminated hb-Pl based on monomer combination 4,4-(hexafluoroisopropylidene)diphthalic anhydride/tris(4-aminophenyl)amine (6EDA/TAPA) was also prepared. Scheme 33 shows the monomer combinations used for the preparation of (S-hb-Pl). 

Chen H, Yin J (2003) Preparatirai of auto-photosensitive hyperbranched co-polyimide by the condensation of 4,4 -(hexafluoroisopropylidene)diphthalic anhydride and 3,3, 4,4 -benzophenonetetracarboxylic dianhydride with l,3,5-tris(4-aminophenoxy)benzene through a stage addition reaction method. Polym Bull 50 303—310... 

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