Monomers Containing Trifluoromethyl Groups

The introduction of fluorine in the form of trifluoromethyl groups (-CF3) in polymer lead to great benefits for improving polymer solubility. This is due to the increase of fractional free volume that limits chain packing density and hence increases solubility and process-ability. We have reported several new aromatic diamine monomers containing trifluoromethyl groups for the synthesis of soluble and 

In general aromatic PAs can be synthesized by two different pathways. The most common methods for the preparation of aromatic PAs are the reaction of diacid dichlorides with diamines at low temperatures or direct condensation reactions in solution of aromatic diacids with diamines at high temperatures. 

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I.S. Chung, S.Y. Kim, Poly(arylene ether)s via nitro displacement reaction synthesis of poly(biphenylene oxide)s containing trifluoromethyl groups from AB type monomers. Macromolecules 33 (26)(2000) 9474-9476. 

Bis(trifluoromethyl)-4,5-difluoro-l,3-dioxole represents the monomer of a new family of amorphous fluoropoiymers (Teflon AF, DuPont) with unusual properties [89JFC(45)100]. Novel fluorinated 2,2-bis(triflu-oromethyl)dioxolanes containing alkyne groups have been synthesized from hexafluoroacetone and propargylic alcohol, bromomethyloxirane, or 1,2-bis(bromomethyl)oxirane [90MI1 91JFC(52)I59] (Scheme 95). 

A new double adamantyl-substituted aromatic bisphenol monomer, 4,8-bis (l-adamantly)-l,5-dihydroxynaphthalene (AdNp) was successfully S5mthesized via the Friedel-Crafts reaction as depicted Scheme 10.11, and two new PAEKs containing adamantly groups (Ad-PAENKs) were synthesized based on the new monomer of AdNp, (3-trifluoromethyl)phenyl hydroquinone (3FHQ) and 4,4 -difluorobenzophenone (D ) via the nucleophilic aromatic substitution polymerization as depicted Scheme 10.12. 

To see the effect of cardo moiety on gas separation properties, Banerjee et al. synthesized five phenyl-substituted phthalimidine side group-containing semifluorinated PAEs, entries 2GS-37 to 2GS-41) (Table 2.11) [102]. These PAEs were synthesized by aromatic nucleophilic substitution, starting from A-phenyl-3,3-fc/5(4-hydroxyphenyl)phthalimidine with five different perfluoroalkylated monomers l,3- 7/5(4 -fluoro-3 -trifluoromethyl benzyl) benzene. 

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